Evaluation of Safety and Effectiveness of Lobster Dynamic Interspinous Spacer in Lumbar Spinal Stenosis: A Single Arm, Prospective, Mutli-Center Study
Phase: NA
Conditions: Spinal Lumbar Stenosis, Claudication, Intermittent
Sponsor: Diametros Medical srl

Clinical Investigational Plan 
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TITLE PAGE 
CLINICAL INVESTIGATIONAL PLAN (CIP) 
EVALUATION OF SAFETY AND EFFECTIVENESS OF LOBSTER DYNAMIC 
INTERSPINOUS SPACER IN LUMBAR SPINAL STENOSIS: A SINGLE ARM, 
PROSPECTIVE, MUTLI-CENTER STUDY 
Protocol Number:LB2CT01 
Version: 1.0 
Date: 08-09-2022 
Sponsor: 
Diametros Medical srl 
via di Terranuova 48/5 
Montevarchi 52025, Arezzo, Italia 
Phone: +39 338 7845689 
Sponsor Contact: 
Gianni Garlatti 
General Manager 
Email: g.garlatti@diametrosmed.com 
Phone: +39 338 7845689 

 
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This document contains confidential information for use only by investigators participating in the 
clinical investigation. This document should be maintained in a secure location and should not be 
copied or made available for review by unauthorized personnel. 

 
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REVISION HISTORY 
 
Version 
Date 
Summary of Changes 
1.0 
08-09-2022 
Original Version 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
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PROTOCOL APPROVAL SIGNATURE PAGE 
 
Protocol Number: LB2CT01 
Protocol Name: Evaluation of Safety and Effectiveness of Lobster Dynamic Interspinous Spacer in 
Lumbar Spinal Stenosis: A Single Arm, Prospective, Mutli-Center Study 
Protocol Version: 1.0 
Protocol Date: 08-09-2022 
 
 
This protocol has been read and approved by: 
 
SPONSOR: 
 
 
 
 
 
 
 
 
 
09 / 08 / 2022 
Gianni Garlatti 
General Manager 
Diametros Medical srl 
 
Date (dd/mmm/yyyy) 
 
 
 
 

 
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INVESTIGATOR PROTOCOL SIGNATURE PAGE 
 
I have read and understand this protocol and will conduct the study in accordance with this protocol.   
I will work consistently with the ethical principles that have their origin in the Declaration of Helsinki 
and that are consistent with good clinical practices, ISO14155 norm, ICH-GCP as far as applicable, 
and the local legally applicable requirements.  
 
 
In my formal capacity as Investigator, my duties include ensuring the safety of the study subjects 
enrolled under my supervision and providing Diametros Medical with complete and timely 
information, as outlined in the protocol.  It is understood that all information pertaining to the study 
will be held strictly confidential and that this confidentiality requirement applies to all study staff at 
this site. 
 
Protocol Number: LB2CT01 
 
Protocol Title: Evaluation of Safety and Effectiveness of Lobster Dynamic Interspinous Spacer in 
Lumbar Spinal Stenosis: A Single Arm, Prospective, Mutli-Center Study 
 
Protocol Version: 1.0  
 
Protocol Date:  08-09-2022 
 
Principal investigator at the local investigational site and PI Deputy and any additional required signatories:  
 
 
Investigator: 
 
STEFANO MARCIA 
 
 
(Print Name) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
09 / 08 / 2022 
(Signature) 
Date (dd/mmm/yyyy) 
 
 
 
 
Upon signing, send a copy of this page to the Sponsor and retain a copy for your files. 

 
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TABLE OF CONTENTS 
 
TITLE PAGE ....................................................................................................................................... 1 
PROTOCOL APPROVAL SIGNATURE PAGE ............................................................................... 4 
INVESTIGATOR PROTOCOL SIGNATURE PAGE ....................................................................... 5 
LIST OF ABBREVIATIONS ............................................................................................................ 10 
1. 
Study Summary ....................................................................................................................... 12 
2. 
Investigation Administration .................................................................................................. 17 
3. 
Introduction ............................................................................................................................. 19 
3.1 
Disease State – Moderate Spinal Stenosis........................................................................... 19 
3.2 
Diagnosis and Current Treatment Options .......................................................................... 21 
3.2.1 
Conservative Care ........................................................................................................ 22 
3.2.2 
Surgical Treatment ....................................................................................................... 22 
3.3 
Clinical Evidence to Date .................................................................................................... 24 
3.4 
Justification for the design of the clinical investigation ...................................................... 26 
4. 
Investigational Device ............................................................................................................ 26 
4.1 
Description of investigational device .................................................................................. 26 
4.2 
Details of the manufacturer of the investigational device ................................................... 29 
4.3 
Device approval status ........................................................................................................ 29 
4.4 
Indications for Use .............................................................................................................. 29 
4.5 
Device supply and STorage................................................................................................. 30 
4.6 
Return, Analysis or Destruction of the Medical Device ..................................................... 30 
5. 
Benefit-Risk Analysis ............................................................................................................. 30 
5.1 
Risks .................................................................................................................................... 30 
5.1.1 
Risks associated with MRI, CT Scans, and X-rays ..................................................... 31 
5.1.2 
Women of child-bearing potential ............................................................................... 32 
5.1.3 
Unknown Potential Risks ............................................................................................. 32 
5.2 
Risk Mitigation .................................................................................................................... 32 
5.3 
Anticipated Benefits ............................................................................................................ 32 
5.4 
Risk-to-Benefit Ratio .......................................................................................................... 33 
6. 
Study Objectives ..................................................................................................................... 33 
6.1 
Primary Objectives .............................................................................................................. 33 
6.2 
Secondary Objectives .......................................................................................................... 33 
7. 
Study Design ........................................................................................................................... 33 
7.1 
Study Duration .................................................................................................................... 34 

 
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7.2 
Treatment/Control Groups .................................................................................................. 34 
7.3 
Methods for minimising bias............................................................................................... 34 
7.4 
Primary Endpoints ............................................................................................................... 34 
7.5 
Secondary Endpoints ........................................................................................................... 34 
7.6 
Radiographic Assessments .................................................................................................. 35 
8. 
Selection of Study Population ................................................................................................. 35 
8.1 
Subject Recruitment ............................................................................................................ 35 
8.2 
Inclusion Criteria ................................................................................................................. 35 
8.3 
Exclusion Criteria ................................................................................................................ 36 
8.4 
Study Enrollment Procedures .............................................................................................. 37 
8.4.1 
Recruitment and screening ........................................................................................... 37 
8.4.2 
Patient Informed Consent ............................................................................................ 37 
8.4.3 
Subject Identification ................................................................................................... 38 
8.5 
Screen Failures .................................................................................................................... 38 
8.6 
Subject Treatment Assignment ........................................................................................... 39 
9. 
Technical and Treatment Failures ........................................................................................... 39 
10. 
Study Procedures .................................................................................................................... 39 
10.1 
Informed Consent (ICF) ...................................................................................................... 39 
10.2 
Screening Visit [WITHIN 60 DAYS Of SURGERY] ............................................................ 40 
10.3 
Surgery/Treatment Visit (Day 0)......................................................................................... 40 
10.4 
6-Week (+/- 14 days), 3-MONTH (+/- 14 days), 6-MONTH (+/- 29 days), 12-MONTH (+/- 
60 days), 24-MONTH (+/- 60 days)  Post-Operative Visit ............................................................ 41 
10.5 
Late and Missed Visits ........................................................................................................ 42 
10.6 
Unscheduled Visits .............................................................................................................. 42 
10.7 
Study Completion/Discontinuation ..................................................................................... 43 
10.8 
Data Collection Summary ................................................................................................... 43 
11. 
Description of Study Procedures ............................................................................................ 45 
12. 
Early Discontinuation for Subjects ......................................................................................... 46 
12.1 
Withdrawals ........................................................................................................................ 46 
12.2 
Lost to Follow-Up (LTFU) ................................................................................................. 47 
12.3 
Documentation of Early Discontinuation ............................................................................ 47 
12.4 
Use of Data from Early Discontinuation Cases .................................................................. 47 
12.5 
Ongoing Treatment for Early Discontinuation Cases ......................................................... 47 
13. 
Study Suspension or Early Termination ................................................................................. 47 
13.1 
Procedure for Suspension or Early Termination ................................................................. 47 

 
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13.2 
Procedure for Resuming the Clinical Investigation After Temporary Suspension ............. 48 
13.3 
Routine Close-Out ............................................................................................................... 48 
14. 
Protocol Deviations ................................................................................................................. 49 
15. 
CONCOMITANT Medications/Therapies ............................................................................. 49 
16. 
Safety Reporting ..................................................................................................................... 50 
16.1 
Definition and Assessment of (Serious) Adverse Events and other safety related events .. 50 
16.1.1 
Adverse Device Effect ................................................................................................. 50 
16.1.2 
Adverse Event (AE) ..................................................................................................... 50 
16.1.3 
Device deficiency (DD) ............................................................................................... 51 
16.1.4 
Device Malfunction ..................................................................................................... 51 
16.1.5 
Incident ........................................................................................................................ 51 
16.1.6 
Serious Adverse Device Effect (SADE) ...................................................................... 51 
16.1.7 
Serious Adverse Event (SAE) ...................................................................................... 51 
16.1.8 
Serious Incident ........................................................................................................... 51 
16.1.9 
Serious Public Health Threat ....................................................................................... 52 
16.1.10 
Unanticipated Serious Adverse Device Effect (USADE) ........................................ 52 
16.1.11 
Use Error .................................................................................................................. 52 
16.2 
Classification ....................................................................................................................... 52 
16.2.1 
Severity ........................................................................................................................ 52 
16.2.2 
Relationship ................................................................................................................. 52 
16.2.3 
Adverse events categorization ..................................................................................... 54 
16.3 
Reporting Procedures and Timelines .................................................................................. 54 
16.3.1 
Documentation ............................................................................................................. 54 
16.3.2 
Reporting of Safety related events to Sponsor ............................................................. 55 
16.3.3 
Reporting of Safety related events to Ethics Committee ............................................. 56 
16.3.4 
Periodic Safety Reporting ............................................................................................ 56 
16.3.5 
Other reporting ............................................................................................................. 56 
16.3.6 
Pregnancy Reporting .................................................................................................... 56 
16.4 
Treatment of AEs ................................................................................................................ 56 
16.5 
Secondary Surgical Interventions (SSIs)............................................................................. 56 
16.6 
Safety Oversight: Clinical Events Committee (CEC) ......................................................... 57 
17. 
Clinical Monitoring ................................................................................................................. 57 
17.1 
Site Monitoring ................................................................................................................... 57 
17.2 
Monitoring Activities .......................................................................................................... 57 
17.3 
Frequency of Visits ............................................................................................................. 58 

 
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18. 
Audits and Inspections ............................................................................................................ 58 
19. 
Statistical Methods .................................................................................................................. 59 
19.1 
Analysis Sets ....................................................................................................................... 59 
19.2 
Primary Endpoint ................................................................................................................ 59 
19.3 
Sample Size Assessment ..................................................................................................... 60 
19.4 
Safety Analyses ................................................................................................................... 60 
19.5 
Secondary effectiveness ...................................................................................................... 61 
19.6 
Missing Data/Sensitivity Analysis ...................................................................................... 61 
19.7 
Pooling and Subgroups........................................................................................................ 61 
20. 
Ethics & Regulatory Aspects .................................................................................................. 61 
20.1 
Ethical Conduct ................................................................................................................... 61 
20.2 
Reporting to Ethics Committee (IEC) and Competent Authority ....................................... 62 
20.3 
Study Amendments ............................................................................................................. 62 
20.4 
Insurance ............................................................................................................................. 62 
21. 
Data Handling and Recordkeeping ......................................................................................... 62 
21.1 
EDC and eCRFs .................................................................................................................. 62 
21.2 
Data security, access and back-up ....................................................................................... 63 
21.3 
Electronic and central data validation ................................................................................. 63 
21.4 
Capture of patient reported outcomes ................................................................................. 64 
21.5 
Archiving of essential clinical investigation documents ..................................................... 64 
21.6 
Storage of biological material and related health data ........................................................ 64 
21.7 
Publication and Data Sharing Policy ................................................................................... 64 
21.8 
Participant and Data Confidentiality ................................................................................... 64 
21.9 
Subject Records ................................................................................................................... 65 
22. 
Funding and Support ............................................................................................................... 65 
23. 
References ............................................................................................................................... 66 

 
Clinical Investigational Plan 
 
 
 
 
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LIST OF ABBREVIATIONS   
 
AE 
Adverse Event 
AIDS 
Acquired Immunodeficiency Syndrome 
AP 
Anteroposterior 
ASTM 
American Society for Testing and Materials 
CDRH 
Center for Devices and Radiological Health 
CEC 
Clinical Events Committee 
CFR 
Code of Federal Regulations 
CRF 
Case Report Form 
CRO 
Contract Research Organization 
CT 
Computed Tomography or CAT Scan 
DDD 
Degenerative Disc Disease 
DEXA 
Dual-Energy X-ray Absorptiometry or Bone Density test 
DHHS 
U.S. Department of Health and Human Services 
DSMB 
Data and Safety Monitoring Board 
EC 
Ethics Committee 
eCRF 
Electronic Case Report Form 
EDC 
Electronic Data Capture 
ELI 
Extra Low Interstitials 
EMG 
Electromyography 
EOB 
Explanation of Benefits 
FDA 
U.S. Food and Drug Administration 
GCP 
Good Clinical Practice 
HIPAA 
Health Insurance Portability and Accountability Act 
HIV 
Human Immunodeficiency Virus 
ICF 
Informed Consent Form 
ICH 
International Conference on Harmonization of Technical Requirements 
for Registration of Pharmaceuticals for Human Use 
IDE 
Investigational Device Exemption 
IFU 
Instructions for Use 
IMM 
Independent Medical Monitor 
ISO 
International Organization for Standardization 
LSS 
Lumbar Spinal Stenosis 
LTFU 
Lost to Follow-Up 
MRI 
Magnetic Resonance Imaging 

 
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OUS 
Outside United States 
PF 
Physical Function 
PG 
Performance Goal 
PHI 
Personal Health Information 
PI 
Principal Investigator 
PMA 
Premarket Approval 
PRO 
Patient Reported Outcome 
SAE 
Serious Adverse Event 
SAP 
Statistical Analysis Plan 
SAP 
Superior Articulating Process 
SF-12 
12-Item Short Form Survey 
SOC 
Standard of Care 
SOP 
Standard Operating Procedure 
SSED 
Summary of Safety and Effectiveness 
SSI 
Secondary Surgical Interventions 
UADE 
Unanticipated Adverse Device Effect 
VAS 
Visual Analog Scale 
ZCQ 
Zurich Claudication Questionnaire 
 
 

 
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1. STUDY SUMMARY 
Study Full Title 
Evaluation of Safety and Effectiveness of Lobster Dynamic 
Interspinous Spacer in Lumbar Spinal Stenosis: A Single Arm, 
Prospective, Mutli-Center Study 
Study Sponsor 
Diametros Medical srl 
Study Number 
LB2CT01 
Protocol Version and Date 
1.0, 08-09-2022 
STUDY OVERVIEW 
Study Design 
Prospective,multi-center study of the Lobster System in 
patients with moderate lumbar spinal stenosis. 
Purpose 
To demonstrate the safety and effectiveness of the Lobster 
device in comparison to an SSED-based performance goal. 
Expected Study Duration 
2 years, including enrollment and post-operative follow-up  
Number of Subjects & Sites 
Estimated 210 investigational subjectsin up to 3 sites in Italy 
will be enrolled.  
 
Treatment 
All enrolled subjects will be assigned to treatment with the 
Lobster device 
Evaluation Schedule 
Subjects will be evaluated at the following timepoints: 
• Pre-operation 
• 6 weeks 
• 3 months 
• 6 months 
• 
12 months 
• 
24 months, and annual thereafter until final subject 
reaches 12 months 
ELIGIBILITY CRITERIA  
Intended Subject Population 
Lobster Implantable Dynamic Interspinous Device is indicated 
to treat skeletally mature patients suffering from pain, 
numbness, and/or cramping in the legs (neurogenic intermittent 
claudication) secondary to a diagnosis of moderate lumbar 
spinal stenosis, with or without Grade 1 spondylolisthesis, 
confirmed by X-ray, MRI and/or CT evidence by a thickened 
ligamentum flavum, narrowed lateral recess, and/or central 
canal or foraminal narrowing. 
 
Patients must also meet all study inclusion and none of the 
study exclusion criteria. 
Main Inclusion Criteria 
In order to be eligible to participate in this study, subjects must 
meet all of the following criteria: 
 

 
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1. Male or female subjects ≥ 45 years of age.  
2. Persistent leg/buttock/groin pain, with or without back 
pain, that is relieved by flexion activities (example: 
sitting or bending over a shopping cart).   
3. Subjects who have been symptomatic and undergoing 
conservative care treatment for at least 6 months.  
4. Diagnosis of degenerative spinal stenosis of the 
lumbar spine, defined as the narrowing of the midline 
sagittal spinal canal (central) and/or narrowing 
between the facet superior articulating process (SAP), 
the posterior vertebral margin (lateral recess), and the 
nerve root canal (foraminal).  
5. Radiographic confirmation of at least moderate spinal 
stenosis which narrows the central, lateral, or 
foraminal spinal canal at one or two contiguous levels 
from L1-L5. Moderate spinal stenosis is defined as 
25% to 50% reduction in lateral/central foramen 
compared to the adjacent levels, with radiographic 
confirmation of any one of the following:  
a) Evidence of thecal sac and/or cauda equina 
compression.  
b) Evidence of nerve root impingement 
(displacement or compression) by either osseous 
or non-osseous elements.  
c) Evidence of hypertrophic facets with canal 
encroachment. 
 
Note: All imaging studies used to confirm LSS are to be 
completed within 3 months prior to enrollment. Radiographic 
(imaging) confirmation of LSS included MRI and/or CT. In 
the case of a transitional L5/L6 segment with a sufficiently 
prominent L6 spinous process, these subjects may be included 
by a deviation request from the applicant. 
 
6. Must present with moderately impaired Physical 
Function (PF) defined as a score of > 2.0 of the Zurich 
Claudication Questionnaire (ZCQ).  
7. Must be able to sit for 50 minutes without pain and to 
walk 15 meters (50 feet) or more . 
8. Subjects who are able to give voluntary, written 
informed consent to participate in this clinical 
investigation and from whom consent has been 
obtained.  
9. Subjects, who, in the opinion of the Clinical 
Investigator, are able to understand this clinical 
investigation, cooperate with the investigational 

 
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procedures and are willing to return for all the required 
post-treatment follow-ups. 
Main Exclusion Criteria 
Subjects who meet any of the following criteria will be 
excluded from participating in this study: 
 
1. Axial back pain only. 
2. Fixed motor deficit. 
3. Diagnosis of lumbar spinal stenosis which requires 
any direct neural decompression or surgical 
intervention other than those required to implant the 
control or investigational device. 
4. Unremitting pain in any spinal position. 
5. Significant peripheral neuropathy or acute denervation 
secondary to radiculopathy. 
6. Lumbar spinal stenosis at more than two levels 
determined pre-operatively to require surgical 
intervention. 
7. Significant instability of the lumbar spine as defined 
by ≥ 3mm translation or ≥ 5° angulation. 
8. Sustained pathologic fractures of the vertebrae or 
multiple fractures of the vertebrae and/or hips. 
9. Spondylolisthesis or degenerative spondylolisthesis 
greater than grade 1 (on a scale of 1-4). 
10. Spondylolysis (pars fracture). 
11. Degenerative lumbar scoliosis with a Cobb angle of > 
10° at treatment level. 
12. Osteopenia or osteoporosis. To confirm eligibility, at 
the Clinical Investigator’s discretion, the following 
subjects may have a DEXA scan performed: 
i. Women 65 or older 
ii. Postmenopausal women < age 65 
iii. Subjects with major risk factors for or 
diagnosed with osteoporosis or osteopenia 
iv. If DEXA is required, exclusion is defined as 
a DEXA bone density measurement T score 
≤ -2.5 
13. Morbid obesity, defined as Body Mass Index (BMI) 
greater than 40kg/m2. 
14. Insulin-dependent diabetes mellitus. 
15. Significant peripheral vascular disease (diminished 
dorsalis pedis or tibial pulses). 
16. Prior surgery of the lumbar spine. 
17. Cauda equina syndrome (defined as neural 
compression causing neurogenic bowel or bladder 
dysfunction). 

 
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18. Infection in the disc or spine, past or present. 
19. Evidence of active (systemic or local) infection at time 
of surgery. 
20. Active systemic disease such as AIDS, HIV, hepatitis, 
etc. 
21. Paget’s disease at involved segment or metastasis to 
the vertebra, osteomalacia, or other metabolic bone 
disease. 
22. Currently undergoing immunosuppressive therapy or 
long-term steroid use. 
23. Known allergy to titanium or titanium alloys. 
24. Tumor in the spine or a malignant tumor except for 
basal cell carcinoma 25. Known or suspected history 
of alcohol and/or drug abuse. 
25. Prisoner or transient. 
26. Life expectancy less than two years. 
27. Angina, active rheumatoid arthritis, or any other 
systemic disease that would affect the subject’s 
welfare or outcome of the clinical investigation. 
28. Any significant mental illness (e.g., major depression, 
schizophrenia, bipolar disorder, etc.) that could impair 
the consent process or ability to complete subject self-
report questionnaires. 
29. Involved in pending litigation of the spine or worker’s 
compensation related to the back. 
30. Enrolled in the treatment phase of another drug or 
device clinical investigation (currently or within past 
30 days). 
31. Congenital defect of the spine. 
32. Pregnant or lactating.  
33. Any further contraindications and limitations of the 
device as described in the instructions for use (IFU). 
 
STUDY ENDPOINTS  
Primary Endpoint 
Subjects will be evaluated at the 12-month follow-up for the 
primary endpoint. 
 
Efficacy success will be evaluated as a two-prong composite 
endpoint: 
• ZCQ Responder (at least two of the three ZCQ 
domains) 
o ≥0.5 point improvement in physical function. 
o ≥0.5 point improvement in symptom severity 
o Mean satisfaction ≤2.5 points. 

 
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• No secondary surgical intervention (SSI) including re-
operations, revision, removals or supplemental fixation 
or clinical significant confounding treatments (i.e., 
epidural steroid injections at the index level, spinal 
cord stimulators or rhizotomies) through 12 months. 
 
Safety success will be evaluated using precision-based 
statistics to characterize the incidence of major device- or 
procedure-related complications, including:  
• Device integrity failure (dislodgement, migration, or 
deformation). 
• New or persistent worsened neurological deficit at the 
index level. 
• Spinous process fractures. 
• Deep infection, death, or other permanent device 
attributed disability. 
Secondary Endpoints 
• Oswestry Disability Index (ODI) 
• Visual Analogue Scale (VAS) (Back and Leg) 
• SF-12 Short Form Survey (Physical Function and 
Mental Health) 
• Patient satisfaction survey 
• 
Neurologic status 
STATISTICAL CONSIDERATIONS 
Sample Size 
Mimimum of 191 subjects- maximum of 250 subjects 
Primary Effectiveness 
Hypothesis 
The primary effectiveness hypothesis is that the composite 
success rate for the Lobster device is larger than the 
performance goal of 61.1%. 
 
Compliance statement 
This investigation will be conducted in compliance with the 
CIP, the current version of the Declaration of Helsinki, 
ISO14155, ICH-GCP (as far as applicable) as well as all 
national legal and regulatory requirements.  
 
 
 

 
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2. INVESTIGATION ADMINISTRATION 
 
Sponsor and Manufacturer 
Diametros Medical S.r.l. 
Via Frà’ Domenico Buonvicini n.17, 50132 Firenze 
(Italy) 
Via di Terranuova 48/5, 52025 Montevarchi (AR),  
Italy 
+ 39 055 980070 
+39 055 3909868 
info@diametrosmed.com 
www.diametrosmed.com 
TVA: 15673341002 
Study Funding 
Sponsor 
Sponsor Contact 
Gianni Garlatti 
General Manager 
Email: g.garlatti@diametrosmed.com 
Phone: +39 338 7845689 
Electronic Data Capture (EDC) 
SMART-TRIAL ApS 
K. Christensens Vej 2L, 9200 Aalborg, Denmark. 
Clinical Project Manager 
Omar Sabry 
+39 339 5295119 
omar.sabry.h@gmail.com 
Core Imaging Lab 
Alessandro Napoli, MD, Ph.D 
Dipartimento di scienze radiologiche, oncologiche e 
anatomopatologiche, Sapienza Università di Roma, 
professore associato in radiologia interventistica 
Viale Regina Elena 324, 00100, Roma, Italia 
Contatti: 
alessandro.napoli@uniroma1.it 
3357718114 
 
Coordinating Investigator and Investigation site(s) 
 
Coordinating Investigator (PI) 
Stefano Marcia, MD 
Head of Radiology dept. 
SS. Trinità Hospital 
Cagliari – Italy 
+39 335 6512007 
+39 070 6095867 
stefano.marcia@atssardegna.it 
 

 
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Study Sites 
An updated list of all principal investigators and 
investigation sites is maintained and kept separately 
from the CIP. 
 
 
 
 

 
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3. INTRODUCTION 
3.1 
DISEASE STATE – MODERATE SPINAL STENOSIS 
Spinal stenosis is defined as the narrowing of the central spinal canal, nerve root canals, and/or 
intervertebral foramina that leads to compression of the exiting or traversing spinal nerve roots1. 
Symptoms most often occur in patients > 50 years of age, and may therefore have a significant 
negative impact on the elderly population. Data from the Framingham Heart Study indicates that 1% 
of men and 1.5% of women already had evidence of stenosis at baseline (mean age of 54), increasing 
to 11% of men and 25% of women over the 25-year follow-up period2. 
 
A diagnosis of spinal stenosis can have varying degrees of severity, as well as other concomitant 
conditions. Figure 1 provides examples of varying severity of spinal stenosis, as observed 
radiographically. 
 
 
(a) 
 
(b) 
 
(c) 
Figure 1: Coronal MRIs Depicting Differing Severity of Central Spinal Stenosis  
(a) Mild, (b) Moderate, and (c) Severe 
 
At initial presentation, patients may complain of low back pain, buttock pain, leg pain, numbness, 
tingling, cramping, and/or trochanteric and posterior thigh pain that may radiate to the knee, lateral 
thigh, calves, and occasionally the feet3. In the earlier stages of the disease, these symptoms may be 
relieved by sitting or lying down and may be exacerbated by walking, especially downhill4, an 
occurrence known as intermittent neurogenic claudication. While plain radiographs, three-
dimensional imaging methods, and other radiographic measurements are useful in confirming the 
diagnosis of spinal stenosis, a careful clinical history is the necessary means for establishing the 
diagnosis5. In addition to leg/buttock pain, spinal stenosis patients may also complain of debilitating 
low back pain that is most commonly attributed to facet-based arthrosis, degenerative disc disease 
(DDD), or muscular strain.  
 
1 Arnoldi CC, Brodsky AE, Cauchoix J, et al. Lumbar spinal stenosis and nerve root entrapment syndrome. Definition 
and classification. Clin Orthop 1976; 115:4-5. 
2 Treatment of Degenerative Lumbar Spinal Stenosis. Summary, Evidence Report/Technology Assessment: Number 32. AHRQ 
Publication No. 01-E047, March 2001. Agency for Healthcare Research and Quality, Rockville, MD. Available at 
http://www.ahrq.gov/clinic/epcsums/stenosum.htm. 
3 Yong-Hing K, Kirkaldy-Willis WH. The pathophysiology of degenerative disease of the lumbar spine. Orthop Clin 
North Am. 1983;14:501-3. 
4 Delamarter RB, Howard M.: Lumbar spinal stenosis. Rehabilitation of the Spine, Science and Practice. Editors 
Hochschular S, Cotler H., Guyer R, Chapter 37, pp. 443-456, Mosby, 1993.  
5 Deyo RA, Rainville J, Kent DL. What can the history of physical examination tell us about low back pain? JAMA 
1992;268:760-5. 

 
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While spinal stenosis can be congenital, it is most often the result of degenerative changes to the 
spine, typically those observed with aging. Degenerative spinal stenosis typically begins with 
degenerative changes of the nucleus pulposus portion of the intervertebral disc. As the disc 
degenerates and narrows, the vertebrae become more closely positioned to one another, which may 
result in ligament laxity and lead to intersegmental instability6. These changes can lead to osteophyte 
formation, which has the effect of temporarily restabilizing the unstable spinal segment. The presence 
of circumferential osteophytes, together with loss of disc space height, contribute to neural foraminal 
narrowing. As the degenerative changes progress, the ligamentum flavum shortens and buckles, 
producing thickening which may further reduce canal area and contribute to central spinal stenosis7. 
Finally, degenerative changes to the facet joints with secondary osteophyte formation may add a 
component of lateral recess stenosis.  
 
Stenosis can be further classified by the location of neural impingement. Figure 2 presents images of 
foraminal, central, and lateral stenosis. 
 
 
(a) 
(b) 
(c) 
Figure 2: Types of Stenosis: (a) MRI Depicting Foraminal Stenosis (b) MRI Depicting Central Stenosis2 (c) Diagram of Lateral 
Stenosis8 
 
The initial diagnosis of spinal stenosis is usually based on patient history and physical examination, 
typically including a neurological examination. Confirmation of the diagnosis and delineation of both 
the degree of disease and its etiology may be accomplished by imaging methods such as plain 
radiograph, CT scan (with or without myelographic contrast), and MRI, and non-imaging tests such 
as electromyography (EMG)9. Many different parameters have been reported for objectively or semi-
 
6 Fast A, Greenbaum M. Degenerative lumbar spinal stenosis. Phys Med Rehabil St Art Rev 1995; Oct. 9:673-82. 
7 Yong-Hing K, Kirkaldy-Willis WH. The pathophysiology of degenerative disease of the lumbar spine. Orthop Clin 
North Am. 1983;14:501-3. 
8 Botwin, KP, Gruber RD. Lumbar Spinal Stenosis: Anatomy and Pathogenesis. Phys Med Rehabil of Clin N Am 14 
(2003) 1-15 
9 Delamarter RB, Howard M.: Lumbar spinal stenosis. Rehabilitation of the Spine, Science and Practice. Editors 
Hochschular S, Cotler H., Guyer R, Chapter 37, pp. 443-456, Mosby, 1993. 

 
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objectively evaluating the degree of spinal stenosis, most of which evaluate either the anterior to 
posterior (AP) dimension of the spinal canal, or its cross-sectional area10.  
 
The severity of spinal stenosis is often the driving factor in the treatment methodology. Severity can 
range from “mild” stenosis, where tissue impingement on spinal nerves and/or the spinal cord 
manifest symptoms that are generally are treated successfully with conservative (non-surgical) care, 
to “severe” stenosis, where significant amounts of impeding bone and ligamentum flavum need to be 
removed via direct surgical decompression with or without additional mechanical stabilization, to 
address symptoms. In addition, severe spinal stenosis is often associated with significant 
spondylolisthesis or retrolisthesis, creating instability in the spine once a decompression surgery is 
performed that may require stabilization with instrumentation. 
 
It is recognized that spinal stenosis is a progressively degenerative condition that often continues to 
worsen as patients age. Non-surgical or conservative treatments, while effective in early and milder 
stages of the disease, may later prove ineffective as the stenosis worsens. Patients that have continued 
back and leg pain after conservative care has become ineffective are often diagnosed with “moderate” 
stenosis. These patients have progressed to a point where direct decompression is not yet required to 
achieve symptom relief, but where non-operative treatments are no longer effective.  
 
Moderate stenosis is diagnosed clinically through patient symptomatology and is confirmed through 
radiographic criteria. The clinical hallmark of moderate stenosis is persistent leg, buttock, or groin 
pain, with or without back pain, that is relieved by placing the spine in flexion (e.g., leaning forward 
or bending over a shopping cart). These patients are generally no longer responsive to varying non-
surgical treatments to relieve pain. In order to assess the extent of the pain and impaired function, 
validated scoring systems such as the Zurich Claudication Questionnaire can be used. In the clinical 
trials supporting PMA approval of the X-STOP® and VertiFlex Superion devices, moderate stenosis 
was further defined, in part, as patients who present with moderately impaired Physical Function (PF) 
defined as a score of ≥2.0 on the Zurich Claudication Questionnaire. When stenosis reaches a 
moderate severity and non-surgical care no longer mitigates symptoms, the only way to achieve 
sufficient pain relief is through surgical means. 
 
Confirmation of moderate spinal stenosis is obtained by radiographic measurements, often defined as 
25% to 50% reduction in lateral and/or central foraminal area compared to the adjacent levels. In 
addition, the patient can exhibit other radiographic evidence of moderate stenosis, including cauda 
equina compression, nerve root impingement, and hypertrophic facets with canal encroachment. 
 
3.2 
DIAGNOSIS AND CURRENT TREATMENT OPTIONS 
An overall outline of the treatment continuum for spinal stenosis is included in Figure 3. As shown 
by this figure, treatment options for spinal stenosis generally range from non-invasive, or 
conservative, treatments for conditions with milder symptoms, to invasive surgical options for 
moderate to severe stenosis, the latter often compounded by spinal instability. Surgical options range 
from indirect decompression devices (including VertiFlex Superion device) to decompression 
 
10 See, Treatment of Degenerative Lumbar Spinal Stenosis. Summary, Evidence Report/Technology Assessment: Number 
32. AHRQ Publication No. 01-E047, March 2001. Agency for Healthcare Research and Quality, Rockville, MD. 
Available at http://www.ahrq.gov/clinic/epcsums/stenosum.htm. 
 

 
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procedures, with or without the coflex® device, to fusion procedures with stabilizing instrumentation. 
Increased surgical complexity and invasiveness is often associated with increased morbidity. 
 
 
 
 
 
Figure 3: Stenosis Treatment Continuum 
 
3.2.1 Conservative Care  
 
As previously stated, in its early stages, spinal stenosis is primarily treated with physical therapy and 
other non-invasive methods of symptom management. As outlined in the North American Spine 
Society (NASS) guidelines for the treatment of spinal stenosis11, initial treatments for spinal stenosis 
include modifications to daily living (bed rest, activity modification), bracing, medication (NSAIDs, 
opiates), and spinal manipulation. Of these, only bracing has demonstrated sufficient evidence of 
success in the literature, although there is no evidence that results are sustained once the brace is 
removed. For patients who do not respond to conservative care, an epidural steroid injection at the 
symptomatic level(s) is generally the next step in the treatment algorithm. NASS guidelines suggest 
epidural injections to provide short-term (two weeks to six months) symptom relief in patients with 
neurogenic claudication, although these treatments are still focused on symptom management and 
not on treating the underlying disease or pathology. If epidural treatment or pain management does 
not lead to an improved patient outcome, then surgical treatment is outlined as the next step in the 
care continuum. In patients with symptoms of moderate stenosis, non-surgical care has not been, or 
is no longer, effective in mitigating the symptoms of lumbar spinal stenosis. 
 
3.2.2 Surgical Treatment  
 
In the setting of lumbar spinal stenosis and degenerative spondylolisthesis recalcitrant to conservative 
treatment, surgical options have been shown in the recent NIH-funded SPORT trials to produce 
universally excellent results and superiority over non-operative treatment with results sustained at 4 
 
11 North American Spine Society. Clinical Guidelines for Multidisciplinary Spine Care: Diagnosis and Treatment of 
Degenerative Lumbar Spinal Stenosis. 2011. 

 
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years. The SPORT trials are Level 1 evidence and reflect the highest quality studies performed to 
date comparing conservative versus surgical treatment for spinal stenosis12,13,14,15,16,17. Depending on 
the nature of the pathology encountered, there are two types of decompression that can be considered: 
indirect and direct decompression (with the appropriate stabilization). When considering indirect 
decompression, the only currently marketed device is the VertiFlex Superion Indirect Decompression 
System (Boston Scientific). This device is indicated for the treatment of symptoms secondary to 
moderate stenosis and operates by the same mechanism as the subject Lobster device. The direct 
decompression options would consist of laminectomy, laminotomy, foraminotomy, decompression 
with stabilization with coflex® Interlaminar Technology, or laminectomy with posterior 
instrumentation and spinal fusion. Most of these options are indicated for moderate to severe spinal 
stenosis or stenosis in which instability exists.  
  
3.2.2.1 Indirect Decompression 
For those patients that are demonstrating symptoms of neurogenic intermittent claudication secondary 
to moderate stenosis, the VertiFlex Superion Indirect Decompression System can also be considered 
a treatment modality. The VertiFlex Superion Indirect Decompression System has been approved to 
provide indirect neural decompression (i.e., decompression without surgical removal of soft or bony 
tissue impinging neural elements) by acting as an extension blocker, thus inhibiting compression of 
neural elements in extension. In this technique, a direct surgical decompression is not performed, and 
any neurologic recovery is contingent upon adequate indirect neuroforaminal decompression and 
restriction of extension (extension blocking).  
 
3.2.2.2 Direct Decompression 
The goal of most surgical treatments for stenosis is to decompress the nerve roots to relieve leg, groin, 
and/or buttock pain and other symptoms of neurogenic claudication secondary to lumbar spinal 
stenosis. A laminectomy procedure, with or without partial facetectomy, is a direct decompression, 
which removes the source of boney and ligamentous compression of the nerve roots. The treatment 
of spinal stenosis via laminectomy certainly has its place within a surgeon’s armamentarium; however, 
for laminectomy to be a long term successful option, it has to be used for the proper patient. In 
addition, laminectomy procedures can be associated with significant adverse events related to the 
open surgical procedure, such as infection, as well as increased operative time and hospitalization 
following surgery when compared with interspinous spacer placement18. 
 
 
12 Birkmeyer NJ. Design of the Spine Patient outcomes Research Trial (SPORT). 2002. 
13  Pearson A. Degenerative spondylolisthesis versus spinal stenosis: does a slip matter? Comparison of baseline 
characteristics and outcomes (SPORT). 2010. 
14 Tosteson AN. The cost effectiveness of surgical versus nonoperative treatment for lumbar disc herniation over two 
years: evidence from the Spine Patient Outcomes Research Trial (SPORT). 2008. 
15 Weinstein JN. Surgical versus nonsurgical treatment for lumbar degenerative spondylolisthesis. 2007. 
16 Weinstein JN. Surgical compared with nonoperative treatment for lumbar degenerative spondylolisthesis. four-year 
results in the Spine Patient Outcomes Research Trial (SPORT) randomized and observational cohorts. 2009. 
17 Weinstein JN. Surgical Versus Nonoperative Treatment for Lumbar Spinal Stenosis Four-Year Results of the Spine 
Patient Outcomes Research Trial. 2010. 
18 Patil CG, Sarmiento JM, Ugiliweneza B, Mukherjee D, Nuno M, Liu JC, Walia S, Lad SP, Boakye M. Interspinous 
device versus laminectomy for lumbar spinal stenosis: a comparative effectiveness study. Spine J. 2014; 14:1484-92. 

 
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The laminectomy/direct decompression procedure is often able to effectively remove the neurologic 
compression. However, it is well-accepted that decompression alone in patients with spinal stenosis 
and degenerative spondylolisthesis predisposes patients to progression of instability if not stabilized 
at the time of decompression19,20,21. Consequently, lumbar spinal fusion following decompressive 
laminectomy is commonly recommended for this patient cohort to facilitate both neural 
decompression and motion segment stabilization. Here also, the increased complexity and 
invasiveness of the procedure offers greater potential for morbidity. 
 
The coflex® Interlaminar Technology was PMA approved (P110008) for the treatment of spinal 
stenosis. It’s important to recognize coflex® is intended for patients with a greater progression of 
stenosis than the subject patient population (moderate to severe stenosis). coflex® is designed to be 
utilized in conjunction with a decompression surgery to provide additional stabilization.  
 
Spinal fusion has well-documented shortcomings. Fusion surgery is more complex and invasive than 
a laminectomy in that the method for stabilization requires removal of the lamina bone and then 
implantation of pedicle screws and rods into the spine. Surgical dissection out to the tips of the 
transverse processes in order to achieve a posterolateral fusion requires extensive dissection and soft 
tissue trauma, which typically leads to more blood loss, longer operative times, significant scar tissue 
formation, and greater post-operative pain. Further, iliac crest bone graft harvest site pain following 
surgery is common and can be a persistent and debilitating source of continued pain in the post-
operative period, despite having excellent relief from symptoms of spinal stenosis22. Long-term 
sequelae of the altered biomechanical environment may lead to progression of symptomatic disc 
degeneration at adjacent levels. The estimated rate of re-operation for symptomatic adjacent segment 
degeneration following lumbar spinal fusion is 36% at 10 years23.  
 
3.3 
CLINICAL EVIDENCE TO DATE  
Lobster device was certified with clinical evaluation (CER Rev.00 28-11-20) based on 
equivalence demonstrating its compliane with essential safety requirements (MDD 
93/42/EEC), acceptable risk/benefit profile, and clinical performance.  
 
The results of two post-market clinical investigation have been published in peer-reviewed 
journals and provided extensive clinical data on Lobster device.  
Manfré 2020 et al. demonstrated the efficacy and safety of Lobster percutaneously implanted 
interspinous spacers for the relief of degenerative lumbar spinal stenosis (DLSS) in a cohort 
of 688 patients with chronic neurogenic claudication. In this cohort two sub-groups were 
compared: Lobster device only (group A) versus Lobster device  plus polymethyl 
 
19 Herkowitz HN, Kurz LT. Degenerative lumbar spondylolisthesis with spinal stenosis. A prospective study comparing 
decompression with decompression and intertransverse process arthrodesis. J Bone Joint Surg Am. 1991 Jul;73(6):802-
8. 
20 Johnsson KE, Redlund-Johnell I, Uden A, Willner S. Preoperative and postoperative instability in lumbar spinal 
stenosis. Spine 1989; 14(6): 591-593. 
21 Mardjetko SM, Connolly PJ, Shott S. Degenerative lumbar spondylolisthesis: A meta-analysis of literature 1970-1993. 
Spine 1994; 19(20S):2256S-2265S. 
22 Sasso RC, LeHuec JC, Shaffrey C; Iliac crest bone graft donor site pain after anterior lumbar interbody fusion: a 
prospective patient satisfaction outcome assessment. J Spinal Disord Tech. 2005 Feb;18 Suppl:S77-81. 
23 Ghiselli G, Wang JC, Bhatia NN, Hsu WK, Dawson EG Adjacent segment degeneration in the lumbar spine. J Bone 
Joint Surg Am. 2004 Jul;86-A(7):1497-503. 

 
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methacrylate augmentation (group). Only 11.3% of complications were observed in group A 
due to spinous process fractures and bone remodelling, and <1% in group B. Both groups 
showed marked improvement in the patients’ ZCQ scores (3.2 to 1.3) and ODI scores (32 to 
21) comparing pre-operative time with 12-months, with strong patient-reported ZCQ 
satisfaction results (1.7).  
 
Huang et al. 2020 published a commentary on Manfré et al., highlighting how the Lobster 
devices implantation technique elevates the percutaneous approach beyond the minimally 
invasive alternatives of the past. Indeed, interspinous spacers offer an alternative for patients 
deemed challenging candidates for open decompression techniques. Spacers can be placed 
percutaneously and do not hinder future open surgical decompression or fusion. The 
commentary further highlighted that the sheer size of the study (covering a 9-year period) is 
impressive, providing a window for how that data might be improved in the long term, 
particularly for patients with osteoporosis. As a matter of fact, it is important to consider the 
spinous process fracture risk that can be limited with the spinoplasty. This is particularly 
important in eldery patients that may not be ideal surgical candidates; for this population 
documentation of fracture risk prior to the intervention with DEXA scans, or similar diagnostic 
studies, should be considered. 
Pavan et al. 2022 showed that patients treated with this IPS (Lobster device) had significant 
improvement in clinical scores (VAS and ODI) at 3 months and significant increase in cross-
sectional foraminal area at the treated level. Moreover, the study showed that the method of 
percutaneous device implantation carries high technical success with no contraindication for 
subsequent revision surgery if needed. Furthermore, the ability to place this IPS under 
sedation and local anaesthesia with limited reported complications indicates the feasibility for 
these types of minimally invasive procedures, which can be performed in interventional 
radiology departments for the treatment of symptomatic DLSS as a short-stay day-case 
procedure. 
 
A post-market retrospective study is still on-going with the objective to follow-up 225 subjects 
with DLSS treated with Lobster percutaneous interspineous device for 2 years. At the 
moment, data at 6 months (LB2 Retrospective Study 2020) show improvement in pain control 
and functionality. Mean VAS score started at 7.8 before Lobster implantantion and decreased 
to 2.9 at 6 months. Disability assessed with ZCQ score showed that mean pre-operative ZCQ 
was 56.4 and decreased to 28.6 at 6 months. No major complications were described in this 
retrospective study, probably due to the complete percutaneous implantation technique 
avoiding surgical resection of the posterior ligaments. We did not record any recurrence, and 
the three device dislocations were treated with device retrieval and implantation of new 
Lobster device; only one procedure was not completed due to spinous process fracture. The 
retrospective study was performed on 3 different centers; a group of patients (n=172) 
received spinoplasty (introduction of cement inside the spinous processes) to reduce the 
possibility of spinous fractures, reporting better results both in terms of VAS and ZCQ. In 
conclusion, the results of this retrospective study suggests that Lobster is a safe and effective 
minimally invasive percutaneous procedure in DLSS." 
 

 
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Finally, the last Periodic Safety Update Report (Mod. 039-R02 PSUR_rev1) reported a high 
safety profile for the Lobster device without any reports of serious adverse events and 
complaints. 
 
 
3.4 
JUSTIFICATION FOR THE DESIGN OF THE CLINICAL INVESTIGATION 
 
According to Clinical Evaluation Report (Rev 00 28-11-20), there is no necessity for further clinical 
investigations on Lobster device as there are no novel features to investigate and no critical aspects 
that need further investigation. However, the design of a new and prospective clinical investigation 
is needed for international registrations to provide additional clinical data not covered by EU 
requirements. Therefore, the clinical investigation is designed in compliance with ISO 14155:2020, 
according to last CER conclusions, and relevant post-market clinical data discussed in the previous 
paragraph to generate prospective, new, and accurate clinical data on Lobster performance and safety 
to support international registrations outside EU. 
 
 
4. INVESTIGATIONAL DEVICE 
Name of investigational device: Lobster Device 
Class: IIb (Rule 8) 
 
4.1 
DESCRIPTION OF INVESTIGATIONAL DEVICE 
The Lobster device is an implantable dynamic interspinous device, which is positioned between the 
spinous processes of the lumbar spine percutaneously, using a specific instrument set. It consists of a 
cylindrical central body (saddle) and at its ends it has four fins that open simultaneously using the 
internal central auger and limit the lateral movements of the device, preventing possible dislocations.  
 
The whole device is made of medical grade titanium alloy (Ti-Al-4V ELI) compliant with ISO 5832-
3 or ASTM F136 standards. 
 
 
Figure 4-1: Lobster device IDS in closed (left) and open configurations (right) 
The front of the device is pointed, designed to facilitate the introduction of the device between the 
spinous processes.  
 
The Lobster device is available for this trial in multiple sizes, as outlined in Table 4-1. 

 
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Depending on the pathological status of the patient, treatment at one or two contiguous levels may 
be necessary.  
 
Table 4-1: Lobster device IDS Available Sizes 
Device Codes 
Size 
LBT08 
Ø 8 mm 
LBT10 
Ø 10 mm 
LBT12 
Ø 12 mm 
LBT14 
Ø 14 mm 
LBT16 
Ø 16 mm 
 
    
 
Figure 4-2: Alternate Views of Lobster IDS 
 
The Lobster is supplied in a closed configuration, with the fins tightened. After measuring the size 
necessary for the distraction through the use of the probes supplied with the instrument set, the 
device of the chosen size is mounted on the implant holder and inserted in the patient between the 
two spinous processes. Once the saddle reaches center, the device is rotated by 90° and the fins are 
opened, as described in the IFU and in the operating technique, ensuring the stability of the Lobster 
between the spinous processes of the lumbar vertebrae. 
 
The intervention is performed percutaneously using the dedicated instrument set. 
 
The Lobster device works to relieve symptoms stemming from degenerative lumbar spinal stenosis 
by preserving foraminal height, reducing stress on the facet joints, and reducing pressure on the 
posterior annulus. As shown in figure, the device uses its four fins to fix itself in the interspinous 
space. A full surgical technique is attached. 
 
The Lobster device instrument set is described in Table 4-2. 
 
Table 4-2: Lobster device Instrumentation 
LOB-0101 
Implant Holder 
 
 

 
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LOB-0102 
Opening tube for 
implant holder 
 
LOB-0103 
Fixing shaft for 
implant holder 
 
 
LOB-0104 
Quick connect 
cannulated handle 
 
 
LOB-0105 
Guide Wire 
 
 
LOB-0108 
Batting Support for 
dilation tube 03 
 
 
LOB-0201 
Dilation Tube 01 
with quick connect 
for handle 
 
LOB-0202 
Dilation Tube 02 
 
 
LOB-0203 
Dilation Tube 03 
with 2 Tines 
 
 
LOB-0204 
Dilation Tube 04 
with 2 Tines 
 
 
LOB-0205 
Dilation Tube 05 
 
 
LOB-0308 
Implant Probe 8 
mm 
 
 
LOB-0310 
Implant Probe 10 
mm 
 
 
LOB-0312 
Implant Probe 12 
mm 
 
 
LOB-0314 
Implant Probe 14 
mm 
 
 
LOB-0316 
Implant Probe 16 
mm 
 
 
 
More specifics can be found in the Investigator Brochure (IB) of the Lobster device. 

 
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4.2 
DETAILS OF THE MANUFACTURER OF THE INVESTIGATIONAL DEVICE 
   Manufacturing Site:   
Diametros Medical S.r.l. 
Via Frà’ Domenico Buonvicini n.17, 50132 Firenze (Italy) 
Via di Terranuova 48/5, 52025 Montevarchi (AR),  Italy 
+ 39 055 980070 
+39 055 3909868 
info@diametrosmed.com 
www.diametrosmed.com 
15673341002 
 
 
4.3 
DEVICE APPROVAL STATUS 
The procedure will be performed using the Lobester CE marked device. This study will evaluate the 
on-label use of Lobster for the treatment of moderate lumbar spinal stenosis. This device is to be used 
in accordance with the provided Instructions for Use (IFU).  
 
4.4 
INDICATIONS FOR USE 
The Lobster device is indicated as follows:  
 
Lobster Implantable Dynamic Interspinous Device is indicated to treat skeletally mature patients 
suffering from pain, numbness, and/or cramping in the legs (neurogenic intermittent claudication) 
secondary to a diagnosis of moderate lumbar spinal stenosis, with or without Grade 1 
spondylolisthesis, confirmed by X-ray, MRI and/or CT evidence by a thickened ligamentum flavum, 
narrowed lateral recess, and/or central canal or foraminal narrowing.  
 
The Lobster device is indicated for those patients with impaired physical function who experience 
relief in flexion from symptoms of leg/buttock/groin pain, with or without back pain, who have 
undergone at least 6 months of non-operative treatment. The Lobster device may be implanted at one 
or two adjacent lumbar levels in patients in whom operative treatment is indicated at no more than 
two levels, from L1 to L5. 
 
For this intended use, Moderate Degenerative Lumbar Spinal Stenosis is defined as follows: 
• 25% to 50% reduction in the central canal and/or nerve root canal (subarticular, 
neuroforaminal) compared to the adjacent levels on radiographic studies, with radiographic 
confirmation of any one of the following: 
o Evidence of thecal sac and/or cauda equina compression 
o Evidence of nerve root impingement (displacement or compression) by either osseous 
or non-osseous elements 
o Evidence of hypertrophic facets with canal encroachment 
• AND associated with the following clinical signs: 
o Presents with moderately impaired Physical Function (PF) defined as a score of 120 
of the Zurich Claudication Questionnaire (ZCQ) 

 
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o Ability to sit for 50 minutes without pain and to walk 50 feet or more. 
 
4.5 
DEVICE SUPPLY AND STORAGE 
The medical device will be delivered in accordance with the provisions of the goods reception of the 
clinical investigation site and the contract between the Sponsor and the site. The Investigator is 
responsible for using the device in compliance with the Instructions for Use (IFU) provided and in 
accordance with this Clinical Investigation Plan (CIP). Documentation of receipt, disposition, and 
return of all device materials must be maintained by the investigator or his/her designee.  
 
The packaging will be that of the commercialized products and storage should be in accordance with 
the IFU provided. 
 
4.6 
RETURN, ANALYSIS OR DESTRUCTION OF THE MEDICAL DEVICE 
Return, disposal or destruction of the medical device are according to standard procedures.  
 
In case of device deficiencies, including malfunction, usability issues, or inadequacy in the 
information supplied by the manufacturer including labelling, the devices will be returned to the 
sponsor for analysis as per standard procedures.  
 
 
 
5. BENEFIT-RISK ANALYSIS 
Diametros Medical is aware of the associated risks of lumbar spinal stenosis surgical treatment using 
interspinous process spacers. However, interspinous process spacers have been thoroughly 
investigated through clinical studies and literature. Further, Diametros Medical has taken multiple 
steps to mitigate these risks, namely non-clinical and preliminary clinical testing with positive results 
that support the safety and effectiveness of the investigational device. 
5.1 
RISKS 
The potential risks for subjects enrolled in the trial include those related to surgery, lumbar spine 
surgery, interspinous spacers (including the Lobster device and other interspinous spacers) and 
instrumentation, or imaging for the study that are not standard of care. There is always a chance that 
unforeseen risks may occur.  
 
Risks generally associated with any surgery include: 
• 
Anesthetic medication reactions 
• 
Surgery at the incorrect location, side or level 
• 
Blood loss, blood vessel damage, phlebitis or hematoma 
• 
Blood transfusion which may cause circulatory collapse, blood incompatibility, kidney 
damage, hepatitis, infection with HIV 
• 
Myocardial infarction or circulatory problems 
• 
Deep vein thrombosis, pulmonary embolism or thrombus formation in other vessels 
• 
Stroke  
• 
Fever or infection 

 
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• 
Pneumonia 
• 
Injury to muscle, soft tissues or nerves 
• Wound swelling, draining or delayed healing 
• Discomfort and rehabilitation associated with recovery from surgery 
• Inability to perform certain tasks, such as lifting, exercising etc.  
• Death 
Risks associated with lumbar spine surgery include: 
• Damage to nerve roots or the spinal cord causing partial or complete sensory or motor loss 
(paralysis) 
• Loss of bladder and/ or bowel functions 
• Dural leaks (tears in the tissue surrounding and protecting the spinal cord) 
• Instruments used during surgery may break or malfunction which may cause damage to the 
operative site or adjacent structures 
• Fracture, damage or remodeling of adjacent anatomy, including bony structures or soft tissues 
during or after surgery 
• New or worsened back or leg pain 
Risks associated with lumbar spine implants (including the Lobster and other interspinous 
spacers) and associated instruments include: 
• 
Sensitivity or allergy to the implant material 
• 
Failure of the device/ procedure to improve symptoms and/ or function 
• 
Pain and discomfort associated with the operative site or presence of implants 
• 
Implant malposition or incorrect orientation 
• 
Spinous process fracture 
• 
Wear debris which may damage surrounding soft tissues including muscle or nerve 
• 
Scar tissue may form at implant site 
• 
Migration or dislodgement of the implant from the original position so that it becomes 
ineffective or causes damage to adjacent bone or soft tissues including nerves 
• 
Implant may loosen, fatigue, deform, break or disassemble which may require another 
operation to remove the implant and may require another method of treatment 
• 
Re-operation to remove or replace the implant 
 
AEs that might reasonably occur because of placement or attempted placement of the investigational 
product or during follow-up were identified through a risk analysis. No interactions with concomitant 
medications are expected. The Risk Analysis in the device IFU lists clinical risks to the subject 
associated with study participation. 
 
5.1.1 Risks associated with MRI, CT Scans, and X-rays 
MRI scanners produce a strong magnetic field that will pull on magnetic materials and may cause 
unwanted movement of the medical device. The radiofrequency energy and magnetic fields may 

 
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cause heating of the implanted device and the surrounding tissue. X-rays and CT scans expose the 
patient to radiation. Exposure to radiation can add up over a patient’s lifetime. The x-rays/CT scans 
obtained during this study are [as frequent/more frequent] than the number of x-rays/CT scans 
participants would undergo as standard of care for their medical condition. Specific counseling 
regarding radiographic imaging risk will be provided to the patient during the consent process.  
5.1.2 Women of child-bearing potential  
The investigator shall discuss specific risks associated with pregnancy and/or breastfeeding with 
women of child-bearing potential who are being considered as study subjects prior to study 
participation. A pregnancy test will be done to confirm the subject is not pregnant before treatment 
in this study. Subjects must immediately inform the investigator if they become pregnant during the 
study.  
5.1.3 Unknown Potential Risks  
While considerable pre-clinical biomechanical and biocompatibility tests have been performed, as 
well as pilot clinical studies to establish device safety, there is always the possibility of unforeseeable 
risks. Because this is a new type of device, other risks (such as risk to an embryo or fetus if a patient 
were to become pregnant) may also exist that are currently not foreseeable or are unknown. 
 
5.2 
RISK MITIGATION 
Appropriate risk mitigation measures have been taken to initiate implantation of this subject 
population to the experimental device, as described below. 
• 
Selection of only those subjects who meet the enrollment criteria 
• 
Medical staff will carefully monitor subjects’ post-treatment to ensure that any complications 
are detected early 
• Consistent testing methods (i.e., study assessments) will be used by the investigational sites 
throughout the study follow-up period 
• Data from the investigator will be reviewed to ensure an understanding of ongoing study 
results 
• Operators will be trained on the surgical technique prior to site activation 
• Medical staff will be trained on study procedures 
An evaluation of the potential risks associated with use of the Lobster device has been performed to 
minimize the risks associated with the device. The following are some of the ways in which risks 
have been or will be minimized: 
• 
Bench testing and sterilization validation 
• 
Biocompatibility testing adhering to ISO 10993-1 
• 
A retrospective, multi-centered OUS clinical study evaluating the safety and efficacy of the 
Lobster device in patients with neurogenic intermittent claudication (NIC) related to 
foraminal stenosis  
5.3 
ANTICIPATED BENEFITS 
While there is no guarantee that a subject will benefit from taking part in this clinical trial, the 
information gained from this study may help others with this condition in the future. Below are the 
potential benefits from participating in this trial: 

 
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Implantation with the Lobster device may provide relief in leg and/ or back pain and other symptoms 
of lumbar spinal stenosis and the provision of motion of the lumbar spine, which may lead to 
increased functional capacity. The Lobster device may also help to relieve stress at other spinal levels 
when compared to a fusion procedure.  
5.4 
RISK-TO-BENEFIT RATIO 
All applicable risks have been addressed through appropriate testing and clinical monitoring. Any 
residual risks are acceptable when weighed against the potential benefits to the subject. The device is 
appropriate for the intended use and is designed to protect the health and safety of the subject, user, 
and environment. 
 
Therefore, the risk/benefit profile of the Lobster device in the intended use justifies the conduct of 
the proposed clinical investigation. 
 
6. STUDY OBJECTIVES 
6.1 
PRIMARY OBJECTIVES 
The primary objective of this study is to demonstrate the safety and effectiveness of the Lobster 
device in comparison to an SSED-based performance goal (PG). This clinical study is a prospective, 
multi-centered study with a historical control designed to support future international regulatory 
registrations   
 
6.2 
SECONDARY OBJECTIVES 
Secondary objectives include documenting clinical outcomes such as low back pain, back and leg 
pain, physical function and mental health, neurological status and treatment satisfaction following 
surgical procedure with Lobster device. 
 
Additionally, this study will evaluate device position and condition as well as integrity of the spinous 
processes via imaging studies. 
7. STUDY DESIGN 
Diametros is proposing a prospective multi-centre study with comparison to an SSED-based 
performance goal (PG). The proposed prospective clinical study will be actively and intentionally 
harmonized to previously cleared interspinous device studies, the Vertiflex Superion RCT (P140004). 
Prospectively defined evaluations of covariate balance and safety evaluations are included in the 
study design, supporting using a performance goal comparison for the primary endpoint. The 
proposed prospective clinical study is summarized in the table below. The inclusion/exclusion 
criteria, device indication, study population, study evaluations as well as follow-up intervals through 
1-year are identical to that of the Superion RCT. This was done as part of the study design regime to 
promote and support the use of a Performance Goal comparison for the primary endpoint. 
 
This clinical study is a prospective, multi-centered study using a historical control. 

 
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7.1 
STUDY DURATION 
The expected study duration is three (3) years, including enrollment (12 months) and post-operation 
follow-ups (24 months). The primary endpoint will be evaluated at 12 months as described in Section 
7.4. 
7.2 
TREATMENT/CONTROL GROUPS 
Enrolled patients meeting all inclusion and exclusion criteria will be treated with the Lobster device.  
 
There is no active control group. The study will utilize a historical control based on publicly available 
SSED data for already-approved interspinous devices, namely Superion and X-Stop. Both Superion 
and X-Stop are approved interspinous devices, appropriate control comparators, and have been 
demonstrated to be non-inferior. Given that both arms arise from the same randomized and FDA-
reviewed clinical trial and the similarity of outcomes, it would be reasonable to design a study where 
control patients are treated with either Superion or X-Stop devices. 
 
7.3 
METHODS FOR MINIMISING BIAS 
Methods to minimize bias include use of validated questionnaires, review of imaging by an 
independent core laband safety review by independent Clinical Events Committee. This study is 
single-arm; therefore, there is no concern of bias from lack of randomization or blinding.  
7.4 
PRIMARY ENDPOINTS 
Subjects will be evaluated at the 12-month follow-up for the primary endpoint. 
 
Efficacy success will be evaluated as a two-prong composite endpoint: 
• 
ZCQ Responder (at least two of the three ZCQ domains) 
o ≥0.5 point improvement in physical function 
o ≥0.5 point improvement in symptom severity 
o Mean satisfaction ≤2.5 points 
• 
No secondary surgical intervention (SSI) including re-operations, revision, removals or 
supplemental fixation or clinical significant confounding treatments (i.e., epidural steroid 
injections at the index level, spinal cord stimulators or rhizotomies) through 12 months 
Safety success will be evaluated using precision-based statistics to characterize the incidence of major 
device- or procedure-related complications, including: 
• 
Device integrity failure (dislodgement, migration, or deformation) 
• 
New or persistent worsened neurological deficit at the index level 
• 
Spinous process fractures 
• 
Deep infection, death, or other permanent device attributed disability 
7.5 
SECONDARY ENDPOINTS 
• 
ODI 
• 
VAS (Back and Leg) 
• 
SF-12 Short Form Survey (Physical Function and Mental Health) 
• 
Patient satisfaction survey 

 
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• 
Neurologic status 
7.6 
RADIOGRAPHIC ASSESSMENTS  
An independent radiographic core laboratory will be used to provide an unbiased assessment of all x-
rays and CT scans (pre-procedure through last follow-up assessment). All images will be evaluated 
in accordance with the Image Review Charter which is provided to the sites.  
 
Radiographic evaluations include: 
• 
Angular Range of Motion 
• 
Translational Motion 
• 
Device Condition 
• 
Device Migration 
• 
Device Dislodgement 
• 
Bone-Implant Interface Changes 
• 
Exuberant Bone Formation 
Outside of this clinical investigation, in normal clinical practice, radiography or computed 
tomography is performed: before surgery, at the end of surgery, and as a follow-up at 6 months, 12 
months, and 24 months. Consequently, the diagnostic activities at 6 weeks and 3 months are to be 
considered additional procedures to normal clinical practice and as such represent an increased risk. 
MRI scanners produce a strong magnetic field that attracts magnetic materials and can cause 
unwanted movement of the medical device. Radiofrequency energy and magnetic fields can cause 
heating of the implanted device and surrounding tissue. X-rays and CT scans expose the patient to 
radiation. Radiation exposure can accumulate over the patient's lifetime. The X-rays obtained during 
this study are more frequent than the number of X-rays participants would undergo as a standard of 
care for their medical condition. The patient will be given specific counseling about the risk of 
radiographic imaging during the consent process. 
 
As discussed above, the diagnostic activities at 6 weeks and 3 months are to be considered additional 
procedures to normal clinical practice and as such represent an increased risk, however, these are 
essential procedures to meet the proposed objectives of this clinical investigation. All other diagnostic 
criteria in the clinical investigation are not considered burdensome and/or invasive. 
 
8. SELECTION OF STUDY POPULATION 
8.1 
SUBJECT RECRUITMENT 
Subjects participating in this study will be recruited from the investigators’ standard patient 
populations. All patients presenting for treatment of lumbar spinal stenosis will be evaluated for study 
participation based on the inclusion/exclusion criteria listed below. Subjects must meet all of the 
following inclusion criteria and none of the exclusion criteria. The investigator maintains exclusive 
responsibility for the inclusion and exclusion of any potential study participant.  
8.2 
INCLUSION CRITERIA 
In order to be eligible to participate in this study, subjects must meet all of the following criteria: 
1. Male or female subjects ≥ 45 years of age. 

 
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2. Persistent leg/buttock/groin pain, with or without back pain, that is relieved by flexion activities 
(example: sitting or bending over a shopping cart) 
3. Subjects who have been symptomatic and undergoing conservative care treatment for at least 6 
months. 
4. Diagnosis of degenerative spinal stenosis of the lumbar spine, defined as the narrowing of the 
midline sagittal spinal canal (central) and/or narrowing between the facet superior articulating 
process (SAP), the posterior vertebral margin (lateral recess), and the nerve root canal (foraminal). 
5. Radiographic confirmation of at least moderate spinal stenosis which narrows the central, lateral, or 
foraminal spinal canal at one or two contiguous levels from L1-L5. Moderate spinal stenosis is 
defined as 25% to 50% reduction in lateral/central foramen compared to the adjacent levels, with 
radiographic confirmation of any one of the following: 
a. Evidence of thecal sac and/or cauda equina compression 
b. Evidence of nerve root impingement (displacement or compression) by either osseous or 
non-osseous elements 
c. Evidence of hypertrophic facets with canal encroachment 
Note: All imaging studies used to confirm LSS are to be completed within 3 months prior to 
enrollment. Radiographic (imaging) confirmation of LSS on CT (or MRI if available in lieu of CT). 
In the case of a transitional L5/L6 segment with a sufficiently prominent L6 spinous process, these 
subjects may be included by a deviation request from the applicant. 
 
6. Must present with moderately impaired Physical Function (PF) defined as a score of > 2.0 of 
the Zurich Claudication Questionnaire (ZCQ) 
7. Must be able to sit for 50 minutes without pain and to walk 50 feet or more 
8. Subjects who are able to give voluntary, written informed consent to participate in this clinical 
investigation and from whom consent has been obtained 
9. Subjects, who, in the opinion of the Clinical Investigator, are able to understand this clinical 
investigation, cooperate with the investigational procedures and are willing to return for all 
the required post-treatment follow-ups. 
8.3 
EXCLUSION CRITERIA 
Subjects who meet any of the following criteria will be excluded from participating in this study: 
1. Axial back pain only 
2. Fixed motor deficit 
3. Diagnosis of lumbar spinal stenosis which requires any direct neural decompression or 
surgical intervention other than those required to implant the control or investigational device 
4. Unremitting pain in any spinal position 
5. Significant peripheral neuropathy or acute denervation secondary to radiculopathy 
6. Lumbar spinal stenosis at more than two levels determined pre-operatively to require surgical 
intervention 
7. Significant instability of the lumbar spine as defined by ≥ 3mm translation or ≥ 5° angulation 
8. Sustained pathologic fractures of the vertebrae or multiple fractures of the vertebrae and/or 
hips 
9. Spondylolisthesis or degenerative spondylolisthesis greater than grade 1 (on a scale of 1-4) 
10. Spondylolysis (pars fracture) 

 
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11. Degenerative lumbar scoliosis with a Cobb angle of > 10° at treatment level 
12. Osteopenia or osteoporosis. To confirm eligibility, at the Clinical Investigator’s discretion, 
the following subjects may have a DEXA scan performed: 
i. Women 65 or older 
ii. Postmenopausal women < age 65 
iii. Subjects with major risk factors for or diagnosed with osteoporosis or 
osteopenia 
iv. If DEXA is required, exclusion is defined as a DEXA bone density 
measurement T score ≤ -2.5 
13. Morbid obesity, defined as Body Mass Index (BMI) greater than 40kg/m2 
14. Insulin-dependent diabetes mellitus 
15. Significant peripheral vascular disease (diminished dorsalis pedis or tibial pulses) 
16. Prior surgery of the lumbar spine 
17. Cauda equina syndrome (defined as neural compression causing neurogenic bowel or bladder 
dysfunction) 
18. Infection in the disc or spine, past or present 
19. Evidence of active (systemic or local) infection at time of surgery 
20. Active systemic disease such as AIDS, HIV, hepatitis, etc. 
21. Paget’s disease at involved segment or metastasis to the vertebra, osteomalacia, or other 
metabolic bone disease 
22. Currently undergoing immunosuppressive therapy or long-term steroid use 
23. Known allergy to titanium or titanium alloys 
24. Tumor in the spine or a malignant tumor except for basal cell carcinoma 25. Known or 
suspected history of alcohol and/or drug abuse 
25. Prisoner or transient 
26. Life expectancy less than two years 
27. Angina, active rheumatoid arthritis, or any other systemic disease that would affect the 
subject’s welfare or outcome of the clinical investigation 
28. Any significant mental illness (e.g., major depression, schizophrenia, bipolar disorder, etc.) 
that could impair the consent process or ability to complete subject self-report questionnaires 
29. Involved in pending litigation of the spine or worker’s compensation related to the back 
30. Enrolled in the treatment phase of another drug or device clinical investigation (currently or 
within past 30 days) 
31. Congenital defect of the spine 
32. Pregnant or lactating 
 
8.4 
STUDY ENROLLMENT PROCEDURES 
8.4.1 Recruitment and screening 
All subjects with lumbar spinal stenosis will be considered for screening into the study. Subjects 
expressing an interest in participation will proceed with the consent process as per Section10.1.. 
 
8.4.2  Patient Informed Consent 
Potential patients will be asked to sign a consent form after verbal explanation of the study by the 
consenting PI or appropriate designee.  

 
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The PI explains to each subject the nature of the investigation, its purpose, the procedures involved, 
the expected duration, the potential risks and benefits and any discomfort it may entail. Each subject 
is informed that the participation in the investigation is voluntary and that he/she may withdraw from 
the investigation at any time and that withdrawal of consent will not affect his/her subsequent medical 
assistance and treatment. The subjects are informed that he/she can ask any question, and consult with  
family members, friends, their treating physicians or other experts before deciding about their 
participation in the investigation. Enough time is given to the subjects. 
  
The subjects are informed that authorised individuals other than their treating physician may examine 
his/her medical records. All subjects a given a subject information sheet and a consent form 
describing the investigation and providing sufficient information for the subjects to make an informed 
decision about their participation in the investigation. The formal consent of a subject, using the 
approved consent form, is obtained before the subject is submitted to any investigation procedure. 
The subject should read, understand, and voluntarily agree before signing and dating the informed 
consent form, and is given a copy of the signed document. The consent form is signed and dated by 
the subject and the PI (or her/his designee). The signed consent form it is retained as part of the 
investigation records. 
 
If new information becomes available that can significantly affect a subject's future health and 
medical care that information shall be provided to the subjects affected in written form. If relevant, 
all affected subjects shall be asked to confirm their continuing informed consent in writing. 
 
Consent will not denote enrolment into the study. Subjects are enrolled at the time of incision. 
8.4.3 Subject Identification 
Subjects who consent to participate shall be assigned a unique Subject Identification Number to de-
identify their information. This Subject Identification Number will be captured on the Screening & 
Enrollment Log and used to identify them on all source documents and eCRFs thereafter. 
 
A record of all screened subjects will be maintained in a Screening/Enrollment Log. The date of 
screening, results of screening (included or not) and, if not eligible, the primary reason for excluding 
the subject, enrollment status (enrolled or not) and, if not enrolled, the primary reason will be recorded. 
 
Please note, for purposes of the study population a subject is considered enrolled at the time of 
surgical incision. 
 
8.5 
SCREEN FAILURES 
A screen failure subject is a consented subject that did not receive the index procedure/treatment due 
to withdrawing consent, being withdrawn from the study, or not meeting eligibility requirements for 
treatment.  
 
If a subject signs the ICF but is found ineligible for inclusion in the study prior to or during the 
surgical procedure, the subject will not be advanced any further in this clinical investigation and will 
receive an appropriate alternative treatment as identified by the Investigator. The subject’s signed 

 
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ICF and completed inclusion/exclusion criteria will be retained by the Investigator, and the subject 
will be notified. 
 
NOTE: If a subject does not meet the eligibility criteria during their initial screening, the subject 
cannot be re-evaluated for entry into the study later if deemed appropriate by the Investigator. 
Screening data from the Pre-Op visit and Surgery visit (prior to incision/treatment), including the 
reason for exclusion, will be collected but may not be complete in cases where the subject is 
determined to be a screen failure early in the screening process. The subject’s exclusion from the 
study, and reason for ineligibility, will be documented in the Screening & Enrollment Log. 
8.6 
SUBJECT TREATMENT ASSIGNMENT 
Following screening, all subjects will be assigned to treatment with the Lobster device. 
9. TECHNICAL AND TREATMENT FAILURES 
Technical failures are subjects that are considered eligible for the study per the inclusion and 
exclusion criteria, enrolled at the time of incision, but did not complete the study treatment/ procedure 
due to safety concerns from the implanting surgeon (i.e., anatomical difficulties, issues noted during 
procedure, etc.).  
 
These subjects will be included in the enrollment totals but will be withdrawn from the study and 
follow-up will be discontinued at the time of technical or treatment failure.  
 
Treatment failures are subjects that must undergo a different procedure other than the study treatment 
(i.e. use of a different interspinous spacer or conversion to fusion) due to an intraoperative injury or 
damage to the investigational/ control device during an attempted implantation leading to safety 
concerns and a subsequent change in treatment. These subjects will be included in the enrollment 
totals but will be withdrawn from the study and follow-up will be discontinued at the time of technical 
or treatment failure.  .  
 
Patients that have not passed screening will not be enrolled in the study and further follow-up of these 
patients shall proceed according to the hospital standard procedures. 
 
10. STUDY PROCEDURES 
10.1 INFORMED CONSENT (ICF) 
Potential patients will be asked to sign a consent form after verbal explanation of the study by the 
consenting PI or appropriate designee.  
 
The PI explains to each subject the nature of the investigation, its purpose, the procedures involved, 
the expected duration, the potential risks and benefits and any discomfort it may entail. Each subject 
is informed that the participation in the investigation is voluntary and that he/she may withdraw from 
the investigation at any time and that withdrawal of consent will not affect his/her subsequent medical 
assistance and treatment. The subjects are informed that he/she can ask any question, and consult with  
family members, friends, their treating physicians or other experts before deciding about their 
participation in the investigation. Enough time is given to the subjects. 
  

 
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The subjects are informed that authorised individuals other than their treating physician may examine 
his/her medical records. All subjects a given a subject information sheet and a consent form 
describing the investigation and providing sufficient information for the subjects to make an informed 
decision about their participation in the investigation. The formal consent of a subject, using the 
approved consent form, is obtained before the subject is submitted to any investigation procedure. 
The subject should read, understand, and voluntarily agree before signing and dating the informed 
consent form, and is given a copy of the signed document. The consent form is signed and dated by 
the subject and the PI (or her/his designee). The signed consent form it is retained as part of the 
investigation records. 
 
If new information becomes available that can significantly affect a subject's future health and 
medical care that information shall be provided to the subjects affected in written form. If relevant, 
all affected subjects shall be asked to confirm their continuing informed consent in writing. 
 
Consent will not denote enrolment into the study. Subjects are enrolled at the time of incision. 
 
 
10.2 SCREENING VISIT [WITHIN 60 DAYS Of SURGERY] 
Upon successful documentation of informed consent, a preoperative screening visit will be performed 
within 60 days prior to the patient’s surgery and will serve as a Standard of Care (SOC) evaluation 
by the Investigator to confirm patient eligibility.  
 
NOTE: The subject recruitment and screening process should follow the study enrollment procedures 
outlined in Section 8.4. All Patient Reported Outcome Questionnaires (PRO) should be administered 
prior to any other study visit assessments or procedures being performed to prevent information from 
the examination biasing the subject’s responses. 
• 
Informed consent 
• 
Inclusion/exclusion criteria review 
• 
Demographics collection 
• 
Medical history collection 
• 
Physical examination 
• 
Neurological examination 
• 
Patient Reported Outcome (PRO) Questionnaires 
o VAS (back and leg) 
o ODI 
o SF-12 
o ZCQ 
• Radiographic Imaging 
o X-rays 
o CT scans (or MRI if available in lieu of CT) 
10.3 
SURGERY/TREATMENT VISIT (DAY 0) 

 
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Upon successful completion of the Screening visit and confirmation of subject eligibility the subject 
will return on the day of surgery/treatment and undergo the following: 
 
• 
Final review of inclusion/exclusion criteria 
• 
Pregnancy determination 
• 
Adverse events review 
• 
Review postoperative rehabilitation regimen with the subject 
– 
CT scan to confirm device placement 
 
Surgical Procedure 
• 
The Investigator will perform the operation, as outlined in the Surgical Procedure/Technique 
Guide, with the investigational device 
• 
Surgery start time will be recorded as the time of first incision 
• 
Surgery stop time will be recorded as the time of skin closure 
• 
The surgeon will consider the procedure to be successful once correct device placement is 
confirmed via postoperative radiographic evaluation. 
• 
If the surgeon cannot complete the procedure for any reason, they should treat the patient per 
SOC.  
Post-Surgical Procedures 
• 
Record adverse events and device deficiencies, if applicable  
• 
Review postoperative rehabilitation regimen with the subject 
• 
Review of concomitant medications 
10.4 6-WEEK (+/- 14 DAYS), 3-MONTH (+/- 14 DAYS), 6-MONTH (+/- 29 DAYS), 12-MONTH (+/- 60 
DAYS), 24-MONTH (+/- 60 DAYS)  POST-OPERATIVE VISIT  
To allow the Investigator’s assessment of the subject’s progress, the subject will return for the 6-
Week, 3-Month, 6-Month, 12-Month, and 24-Month visit and undergo the following: 
 
NOTE:  Surveys should be administered prior to performing any other study visit assessments or 
procedures to prevent information from these assessments or procedures biasing the subject’s 
responses. 
 
• 
PROs 
– 
VAS (back and leg) 
– 
ODI 
– 
SF-12 
– 
Patient satisfaction survey 
– 
ZCQ 
▪ 
Neurological examination 

 
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• 
Record any new or updated adverse events and device deficiencies, if applicable  
• 
Radiographic Imaging 
– 
X-rays 
– 
CT scans 
• 
Review postoperative rehabilitation regimen with the subject 
10.5 LATE AND MISSED VISITS 
If a subject fails to return for a scheduled study visit within the visit window defined in the study 
protocol but completes the visit prior to the beginning of the next visit window, that visit is considered 
to have been completed late. A protocol deviation should be documented on the appropriate eCRF. 
 
If a subject fails to return for a scheduled study visit within the visit window defined in the study 
protocol and the next scheduled study visit window opens, that visit is considered to have been missed. 
A protocol deviation should be documented on the appropriate eCRF. 
 
All attempts should be made to schedule the subject for the study visit as soon as possible so that it 
is captured late rather than missed completely. 
10.6 UNSCHEDULED VISITS 
Subjects may be seen for unscheduled postoperative visits as needed. Data from unscheduled visits 
that relate to the index operation will be collected and reported as an Unscheduled Visit for this study. 
Unscheduled visits that do not relate to the index operation should be evaluated on a case-by-case 
basis by the Investigator to determine if they need to be reported as an Unscheduled Visit for this 
study.  
 
For Unscheduled Visits relating to the index operation, the Investigator will assess the subject’s 
progress and perform the following:  
 
• 
PROs 
– 
VAS (back and leg) 
– 
ODI 
– 
SF-12 
– 
Patient satisfaction survey 
– 
ZCQ 
▪ 
Neurological examination 
• 
Record any new or updated adverse events and device deficiencies, if applicable  
• 
Radiographic Imaging 
– 
X-rays 
– 
CT scans 
• 
Review postoperative rehabilitation regimen with the subject 
  

 
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10.7 STUDY COMPLETION/DISCONTINUATION 
The completion of this clinical investigation will be with the final follow-up visit (at 12 months) of 
the last enrolled patient. At the end of the study,  further follow-up of these patients shall proceed 
according to the hospital standard procedures. 
10.8 DATA COLLECTION SUMMARY 
Table 10-1 below outlines the schedule of visits to be attended by the subject during his/ her 
participation in the study. The schedule spans the subject’s enrollment to their last prescribed follow-
up. Defined in the table are the tasks to be performed by the investigator and subject at each visit, 
including the examination(s) and imaging procedures as well as the types of information to be 
collected. Provided in parentheses next to each visit are the upper and lower acceptable bounds for 
the timing of the visit.  

 
Clinical Investigational Plan 
 
 
 
 
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Table 10-1. Clinical Visits – Scheduling and Requirements 
Activity 
Screening 
(within 
60) days 
prior to 
surgery) 
 Index Procedure 
(Day 0) 
6-week 
(+/- 14 days) 
3-Mo 
(+/- 14 days) 
6-
Mo 
(+/-
28 
days) 
12-
Mo 
(+/- 
60 
days) 
Annual 
thereafter 
until 
final 
subject 
reaches 
12-Mo 
(+/- 60 
days) 
Unscheduled 
Informed Consent 
X 
- 
- 
- 
- 
- 
- 
- 
Inclusion/Exclusion 
Criteria (including 
DXA, if needed) 
X 
X 
- 
- 
- 
- 
- 
- 
Demographics 
X 
- 
- 
- 
- 
- 
- 
- 
Medical History 
X 
- 
- 
- 
- 
- 
- 
- 
Pregnancy Test 
- 
X 
- 
- 
- 
- 
- 
- 
Radiographs 
(standing, lateral, 
neutral) and CT 
X 
X 
X 
X 
X 
X 
X 
X 
ODI 
X 
- 
X 
X 
X 
X 
X 
X 
ZCQ 
X 
X 
X 
- 
X 
X 
X 
X 
X 
X 
VAS 
X 
- 
X 
X 
X 
X 
X 
X 
Patient Satisfaction 
- 
- 
X 
X 
X 
X 
X 
X 
SF-12 
X 
- 
X 
X 
X 
X 
X 
X 
Physical Exam 
X 
- 
X 
X 
X 
X 
X 
X 
Neurological Exam 
X 
- 
X 
X 
X 
X 
X 
X 
Record/Review 
Concomitant 
Medications 
X 
X 
X 
X 
X 
X 
X 
X 
Record/Review 
Adverse Events and 
Device 
Deficiencies 
- 
X 
X 
X 
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Clinical Investigational Plan 
 
 
 
 
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11. DESCRIPTION OF STUDY PROCEDURES 
 
DEMOGRAPHICS 
At screening, subject baseline characteristics including, but not limited to, age, race, and gender, will 
be recorded.  
 
PAST MEDICAL HISTORY 
At screening, each subject’s past medical conditions and surgical procedures will be recorded. 
 
PHYSICAL EXAMINATION 
A standard physical examination, according to the site’s SOC, will be conducted to assess subject’s 
suitability for study participation based on the eligibility criteria. 
 
PREGNANCY DETERMINATION 
A pregnancy test will be performed on female subjects of childbearing potential prior to surgery to 
ensure that the subject is not pregnant before implanting the investigational device. The 
investigational site will conduct the pregnancy test according to its SOC. 
 
 
NEUROLOGICAL ASSESSMENT 
A neurological assessment is an evaluation of the subject’s nervous system. 
 
X-RAY IMAGING 
X-ray views for this study include: Standing, lateral, and neutral. 
 
CT SCAN 
CT scans will be collected at each post-operative follow-up. 
 
DEXA SCAN 
To confirm eligibility, at the Clinical Investigator’s discretion, some subjects may have a DEXA scan 
performed. For the purpose of this study, normal bone density is defined as a DEXA bone density T-
score of >-1, osteopenia will be defined as a T-score ≤-1 and > -2.5, osteoporosis will be defined as 
a T-score ≤ -2.5 (The World Health Organization definition of osteoporosis).  
 
PATIENT REPORTED OUTCOME QUESTIONNAIRES (PROS) 
The following Patient Reported Outcome questionnaires will be completed by the subject and used 
to compare subject outcomes at follow-up time points compared to baseline: 
 
Visual Analog Scale (VAS) Pain Assessments 
VAS is a measurement instrument that measures the amount of pain that a subject feels ranges across 
a continuum from none to an extreme amount of pain. The VAS will be collected for: back, leg. 

 
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Oswestry Disability Index (ODI) 
The ODI is used to quantify disability for low back pain. The self-reported questionnaire contains ten 
sections concerning intensity of pain, lifting, personal care, walking, sitting, sexual function, standing, 
social life, sleeping and traveling. 
 
Zurich Claudication Questionnaire (ZCQ) 
The ZCQ is a self-administered measure to evaluate symptom severity, physical function, and surgery 
satisvation in lumbar spinal stenosis.  
 
SF-12  
The SF-12 Health Survey uses 12 questions to measure functional health and well-being from the 
subject’s point of view and is a validated instrument for collecting Quality of Life data. The survey 
asks subjects for their views about their general health including how they feel and how well they are 
able to perform their usual activities.  
 
 
Treatment Satisfaction 
Treatment Satisfaction is a self-reported questionnaire to measure the subject’s satisfaction of the 
treatment under the protocol.  
 
12. EARLY DISCONTINUATION FOR SUBJECTS 
12.1 WITHDRAWALS 
Subjects have the right to withdraw from the clinical investigation at any time and for any reason 
without prejudice to their future medical care by the investigation team or investigational site. The 
Principal Investigator will ask reason for their withdrawal and will record all information regarding 
the subject discontinuation.  
 
A Subject may be withdrawn from the clinical investigation for the following reasons:  
 
• 
Subjects may choose to withdraw from the clinical investigation under the terms of the 
Declaration of Helsinki and their consent documentation without having to give a reason;  
• 
Any unanticipated adverse event which, in the opinion of the Principal Investigator, is related 
to the treatment and will endanger the well-being of the subject if treatment is continued;  
• 
Development of any intercurrent illness(es), infection or condition(s) that might interfere with 
the clinical investigation;  
• 
Non-compliance with the clinical investigation procedures deemed by the Principal 
Investigator to be sufficient to cause discontinuation;  
• 
Any problem deemed by the Investigator to be sufficient to cause discontinuation.  
 
Regardless of the reason for withdrawal, data available for the subject at the time of withdrawal, 
including the reason for withdrawal, will be entered on the Case Report Forms. All data obtained up 
to the date of withdrawal will be retained unless the patient explicitly requests complete deletion of 
the records, which should be documented by the site.  

 
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The Principal Investigator will treat all subjects discontinued from the investigation due to an 
unanticipated adverse event, directly related to the investigation, until the event resolves or no further 
improvement is expected. A Subject that has been withdrawn from the study after treatment will not 
be replaced. 
12.2 LOST TO FOLLOW-UP (LTFU) 
Subjects who miss the 24-month study visit will be regarded as Lost to Follow-Up. Site staff should 
perform and document a minimum of three attempts to contact them via phone, and one attempt to 
reach them via certified mail to bring them in for the final study visit prior to considering the subject 
LTFU. The staff should document the date and type of attempted communication. 
 
All efforts should be made to have subjects complete all follow-up visits but only subjects that miss 
the 24-month visit will be considered LTFU. 
12.3 DOCUMENTATION OF EARLY DISCONTINUATION  
In every instance where a subject does not complete the study, the Investigator will document the 
primary reason for discontinuation in the subject’s records.  
 
All subjects are free to withdraw from participation at any time, for any reason, specified or 
unspecified, and without prejudice. However, if a subject expresses a desire to withdraw their consent 
for the study, the site should attempt to obtain written documentation for their study records.  
 
For subjects that are discontinued by the Investigator, the Investigator must notify them of their 
discontinuation from the study in writing. 
 
12.4 USE OF DATA FROM EARLY DISCONTINUATION CASES 
Study data collected previously for subjects who withdraw from the study, are discontinued from the 
study by the Investigator or LTFU will be included in the data analysis and clinical study report. 
 
12.5 ONGOING TREATMENT FOR EARLY DISCONTINUATION CASES 
Subjects who withdraw voluntarily or are discontinued by the Investigator will remain eligible for 
SOC treatment by the Investigator and study staff. 
 
13. STUDY SUSPENSION OR EARLY TERMINATION 
13.1 PROCEDURE FOR SUSPENSION OR EARLY TERMINATION 
 
The Sponsor may suspend or prematurely terminate this clinical investigation either at an individual 
investigational site or at all sites. The Sponsor may terminate the investigation prematurely according 
to certain circumstances, for example: 
• Ethical concerns, 
• Insufficient subject recruitment,  
• When the safety of the subject(s) is doubtful or at risk, respectively,  
• Alterations in accepted clinical practice that make the continuation of the investigation unwise, 

 
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• Early evidence of benefit or harm of the experimental intervention. 
 
A Principal Investigator, IEC, or regulatory authority may suspend or prematurely terminate 
participation in this clinical investigation at the investigational sites for which they are responsible. 
 
If suspicion of an unacceptable risk to subjects arises during the clinical investigation, or when so 
instructed by the EC or regulatory authorities, the Sponsor will suspend the clinical investigation 
while the risk is assessed. If an unacceptable risk is confirmed, the Sponsor will terminate the clinical 
investigation. 
 
The Sponsor will consider terminating or suspending the participation of a particular investigational 
site or Investigator if monitoring or auditing identifies serious or repeated deviations on the part of 
an Investigator. 
 
If suspension or premature termination occurs, the terminating party will justify its decision in writing 
and promptly inform the other parties with whom they are in direct communication. 
 
If suspension or premature termination occurs: 
 
The Sponsor will remain responsible for providing resources to fulfill the obligations from this 
protocol and existing agreements for following the subjects enrolled in the clinical investigation, and 
The site’s Principal Investigator or authorized designee will promptly inform the enrolled subjects at 
his/her investigational site 
 
If the study is terminated, Diametros Medical must comply with all applicable government 
regulations and the protocol-required subject follow-up. If discontinuation of the study should occur, 
the Principal Investigator must return all clinical investigation materials  to the Sponsor and provide 
a written statement to the IEC and the regulatory authority(ies)   explaining the reasons for the 
premature termination. All applicable clinical investigation documents shall be subject to the same 
retention policies, as detailed in Section 21.3. 
 
13.2 PROCEDURE FOR RESUMING THE CLINICAL INVESTIGATION AFTER TEMPORARY 
SUSPENSION 
When the Sponsor concludes an analysis of the reason(s) for the suspension, implements the 
necessary corrective actions, and decides to lift the temporary suspension, the Sponsor will inform 
the relevant parties of the rationale and provide them with the relevant data supporting this decision. 
Concurrence will be obtained from the ECs and, where appropriate, regulatory authorities before the 
clinical investigation resumes. If subjects have been informed of the suspension, the Principal 
Investigator or authorized designee will inform them of the reasons for resumption. 
13.3 ROUTINE CLOSE-OUT 
Routine close-out activities will be conducted to ensure that the Principal Investigator's records are 
complete, all documents needed for the Sponsor's files are retrieved, remaining clinical investigation 
materials are disposed of, previously identified issues have been resolved, and all parties are notified. 

 
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14. PROTOCOL DEVIATIONS 
Conformance to the protocol is essential to the quality and integrity of the clinical study. Every effort 
should be made to avoid any deviation from the clinical protocol. A protocol deviation is an event 
whereby the clinical investigator or site personnel did not conduct the study according to the protocol. 
 
Under emergency circumstances, deviations from the protocol to protect the rights, safety and well-
being of human subjects may proceed without prior approval of the Sponsor and the EC. Such 
deviations shall be documented and reported to the Sponsor in the EDC within 5 days of knowledge. 
The EC and regulatory authorities should be notified of the deviation as required by EC reporting 
guidance. 
All deviations will be reported in the eCRF and reviewed by the clinical study manager on a regular 
basis as outlined below. For the purposes of international regulatory submissions, deviations will 
also be reviewed by a Clinical Events Committee. 
The patient must continue to be followed up for safety as described in Section 16. The decision 
regarding the patient’s continuation in the study lies with the investigator.  
Deviations include, but are not limited to the following list: 
Major deviation:  
Any deviation from patient inclusion and exclusion criteria or patient informed consent procedures. 
• 
Failure to obtain proper informed consent (including patient writing the date of consent by 
themselves) prior to conducting study specific activities 
• 
Inclusion/exclusion criteria not met 
• 
Incorrect version of the ICF used 
Minor deviation:  
Deviation from a protocol requirement such as incomplete/inadequate patient testing procedures, 
follow-ups performed outside specified time windows, Adverse Events not reported by investigators 
in the required timeframe as specified in the protocol or source data permanently lost etc. 
 
Site compliance with regard to deviations will be reviewed and analyzed by the clinical study manager 
on a regular basis and corrective and preventative actions will be put in place accordingly. In addition, 
all deviations from the protocol will be documented in the final report.  
 
15.  CONCOMITANT MEDICATIONS/THERAPIES  
For the purposes of this clinical study, only medications taken or administered for the following will 
be recorded: 
 
• 
Pain (any type); 
• 
Inflammation (any type); 

 
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• 
Muscle relaxation; 
• 
Numbness and/or tingling; 
• 
Hormonal replacement therapy; and 
• 
Other medications related to or given for the subject’s lumbar spinal stenosis. 
16. SAFETY REPORTING 
16.1 DEFINITION AND ASSESSMENT OF (SERIOUS) ADVERSE EVENTS AND OTHER SAFETY 
RELATED EVENTS 
AEs/DDs will be reported according to MDR Regulation (EU) 2017/745 and ISO 14155:2020, while 
recognizing and following other specific laws, regulations, directives, standards and/or guidelines, as 
appropriate, as required by the country(ies) in which the study is conducted. 
 
The list of foreseeable AEs and anticipated adverse device effects, together with their likely incidence, 
mitigation or treatment are detailed in the Investigator Brochure (IB) and IFU of the medical device 
used in this study. 
 
As detailed in the CIP, events of the following types are captured for all subjects throughout the study, 
between the start time of enrolment and the end of subject participation (i.e., completion of the study 
or withdrawal of consent). 
 
16.1.1 Adverse Device Effect 
Adverse event (1.2) related to the use of an investigational medical device  
Note 1 to entry: This definition includes adverse events resulting from insufficient or inadequate 
instructions for use, deployment, implantation, installation, or operation, or any malfunction of the 
investigational medical device. 
Note 2 to entry: This definition includes any event resulting from use error or from intentional misuse 
of the investigational medical device. 
Note 3 to entry: This includes ‘comparator’ if the comparator is a medical device. 
(ISO14155:2020,3.1) 
 
16.1.2 Adverse Event (AE) 
Any untoward medical occurrence, unintended disease or injury or any untoward clinical signs, 
including an abnormal laboratory finding, in subjects, users or other persons, in the context of a 
clinical investigation, whether or not related to the investigational device.                               
 (MDR Article 2(57)) 
 
Note: Pre-Existing Medical Conditions; any medical conditions (including planned surgeries and 
planned hospitalizations) present at enrolment, which do not worsen in duration, severity or frequency 
during the study are not adverse events (AE).  These pre-existing medical conditions should be 
adequately documented in the patient’s medical history in the eCRF. Medical conditions present at 
enrolment which worsen after exposure to study treatment will be recorded as an AE on the Adverse 
Event Form of the eCRF. 
At each evaluation, patients should be interviewed in a non-directed manner to elicit potential AEs 
from the patient. The occurrence of an AE will be based on changes in the patient’s physical 

 
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examination, laboratory results, and/or signs and symptoms at a clinical visit, otherwise based on 
information given by the patient over the telephone.  
 
 
16.1.3 Device deficiency (DD) 
Any inadequacy in the identity, quality, durability, reliability, safety or performance of an 
investigational device, including malfunction, use errors or inadequacy in information supplied by 
the manufacturer. 
(MDR Article 2(59)) 
 
16.1.4 Device Malfunction  
Failure of an investigational medical device to perform in accordance with its intended purpose when 
used in accordance with the instructions for use or CIP, or IB. 
(ISO 14155:2020, 3.33) 
 
16.1.5 Incident 
any malfunction or deterioration in the characteristics or performance of a device made available on 
the market, including use-error due to ergonomic features, as well as any inadequacy in the 
information supplied by the manufacturer and any undesirable side-effect. 
(MDR Article 2(64)) 
 
16.1.6 Serious Adverse Device Effect (SADE) 
Adverse device effect that has resulted in any of the consequences characteristic of a serious adverse 
event .  
(ISO14155:2020, 3.44) 
 
16.1.7 Serious Adverse Event (SAE)  
Any adverse event that led to any of the following: 
a) death, 
b) serious deterioration in the health of the subject, that resulted in any of the following: 
i. life-threatening illness or injury, 
ii. permanent impairment of a body structure or a body function, 
iii. hospitalisation or prolongation of patient hospitalisation, 
iv. medical or surgical intervention to prevent life-threatening illness or injury or 
permanent impairment to a body structure or a body function, 
v. chronic disease, 
c) foetal distress, foetal death or a congenital physical or mental impairment or birth defect 
(MDR Article 2(58)) 
 
16.1.8 Serious Incident 
Any incident that directly or indirectly led, might have led or might lead to any of the following:  
(a) the death of a patient, user or other person, 

 
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 (b) the temporary or permanent serious deterioration of a patient's, user's or other person's state of 
health,  
(c) a serious public health threat 
(MDR Article 2(65)) 
 
16.1.9 Serious Public Health Threat 
Means an event which could result in imminent risk of death, serious deterioration in a person's state 
of health, or serious illness, that may require prompt remedial action, and that may cause significant 
morbidity or mortality in humans, or that is unusual or unexpected for the given place and time 
(MDR Article 2(66)) 
 
16.1.10 Unanticipated Serious Adverse Device Effect (USADE) 
Serious adverse device effect which by its nature, incidence, severity or outcome has not been 
identified in the current risk assessment. 
Note 1 to entry: Anticipated serious adverse device effect (ASADE) is an effect which by its nature, 
incidence, severity or outcome has been identified in the risk assessment. 
(ISO14155:2020, 3.51) 
 
16.1.11 Use Error  
User action or lack of user action while using the medical device that leads to a different result than 
that intended by the manufacturer or expected by the user. 
NOTE 1: Use error includes the inability of the user to complete a task. 
NOTE 2: Use errors can result from a mismatch between the characteristics of the user, user interface, 
task or use environment. 
NOTE 3: Users might be aware or unaware that a use error has occurred. 
NOTE 4: An unexpected physiological response of patient is not by itself considered a use error. 
NOTE 5: A malfunction of a medical device that causes an unexpected result is not considered a use 
error. 
(ISO 14155:2020, 3.52) 
 
16.2 CLASSIFICATION  
16.2.1 Severity 
Investigators will assess the severity of the AE and classify it according to the following definitions: 
 
• MILD: The AE is transient or causes mild discomfort. There usually is no intervention/ therapy 
required and the AE does not interfere with the subject’s normal activities. 
• MODERATE: The AE causes some limitation in activity and some assistance may be needed. 
There is no or minimal medical intervention / therapy required. 
• SEVERE: The AE causes marked limitation in activity. The subject’s usual daily activity is 
interrupted. The subject may require medical intervention/ therapy, hospitalization is possible.  
16.2.2 Relationship 

 
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Investigators will assess the potential relationship of the AE or SAE to the use of the Lobster device 
and classify the causality of the event according to the following definitions.  
 
During causality assessment activity, clinical judgement shall be used and the relevant documents, 
such as the Investigator’s Brochure (IB), the Clinical Investigation Plan (CIP) or the Risk Analysis 
Report shall be consulted, as all the foreseeable SAEs and the potential risks are listed and assessed 
there. The presence of confounding factors, such as concomitant medication/treatment, the natural 
history of the underlying disease, and other concurrent illness or risk factors shall also be considered.  
 
The sponsor and the investigators will use the following definitions to assess the relationship of the 
SAE to the investigational device, the comparator or the investigation procedure. 
 
Relationship  
1)  Not related: Relationship to the device, comparator or procedures can be excluded when: 
• the event has no temporal relationship with the use of the investigational device, or the 
procedures related to application of the investigational device; 
• the serious adverse event does not follow a known response pattern to the medical 
device (if the response pattern is previously known) and is biologically implausible; 
• the discontinuation of medical device application or the reduction of the level of 
activation/exposure - when clinically feasible - and reintroduction of its use (or increase 
of the level of activation/exposure), do not impact on the serious adverse event; 
• the event involves a body-site or an organ that cannot be affected by the device or 
procedure; 
• the serious adverse event can be attributed to another cause (e.g. an underlying or 
concurrent illness/ clinical condition, an effect of another device, drug, treatment or 
other risk factors); 
- the event does not depend on a false result given by the investigational device used for 
diagnosis, when applicable; 
In order to establish the non-relatedness, not all the criteria listed above might be met at the 
same time, depending on the type of device/procedures and the SAE. 
 
2) Possible: The relationship with the use of the investigational device or comparator, or the 
relationship with procedures, is weak but cannot be ruled out completely. Alternative causes 
are also possible (e.g. an underlying or concurrent illness/ clinical condition or/and an effect 
of another device, drug or treatment). Cases where relatedness cannot be assessed, or no 
information has been obtained should also be classified as possible. 
 
3) Probable: The relationship with the use of the investigational device or comparator, or the 
relationship  
      with procedures, seems relevant and/or the event cannot be reasonably explained by another 
cause. 
 
4) Causal relationship: the serious adverse event is associated with the investigational device, 
comparator or with  procedures beyond reasonable doubt when: 
• the event is a known side effect of the product category the device belongs to or of 
similar devices and procedures; 

 
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• the event has a temporal relationship with investigational device use/application or 
procedures; 
• the event involves a body-site or organ that 
• the investigational device or procedures are applied to; 
• the investigational device or procedures have an effect on; 
• the serious adverse event follows a known response pattern to the medical device (if 
the response pattern is previously known); 
• the discontinuation of medical device application (or reduction of the level of 
activation/exposure) and reintroduction of its use (or increase of the level of 
activation/exposure), impact on the serious adverse event (when clinically feasible); 
• other possible causes (e.g. an underlying or concurrent illness/ clinical condition 
or/and an effect of another device, drug or 
• treatment) have been adequately ruled out; 
• harm to the subject is due to error in use; 
• the event depends on a false result given by the investigational device used for 
diagnosis10, when applicable; 
 
Where an investigator assessment of causality is not available and/or the causality classification of 
the SAE is still not clear with the information received, the event should be classified as “possible” 
and the reporting not delayed. 
 
16.2.3 Adverse events categorization  
The adverse events are categorized by the PI and the Sponsor using the following algorithm:  
Does the AE meet the seriousness criteria?  
o No, it is not serious  
    • Is the relationship to the device or the procedure possible, probable or causal?  
No: non-related AE  
Yes: ADE 
 o Yes, it is serious: SAE 
     • Is the relationship to the device or the procedure possible, probable or causal? 
   
No: non-related SAE  
Yes: SADE  
o Is it anticipated (within expected type, severity and frequency of the complications)?  
No: unanticipated SADE (USADE)  
Yes: anticipated SADE (ASADE) 
 
 
16.3  REPORTING PROCEDURES AND TIMELINES 
16.3.1 Documentation 
Device deficiencies (DD) and all adverse events (AE) including all serious adverse events (SAE) are 
collected, fully investigated and documented in the source document and appropriate case report form 
(CRF) during the entire investigation period, i.e. from the operating room when the initial incision(s) 

 
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is made to start the implantation procedure until the last CIP specific procedure, including a safety 
follow-up period.   
• Documentation of AEs (including SAEs) by the PI includes diagnosis or symptoms, start 
and stop dates of event, event treatment, event resolution, assessment of severity, 
seriousness and causal relationship to device and/or investigation procedure. 
•  Documentation of DDs by the PI includes description of event, start date, investigational 
device information, action taken with regard to the investigational device, and whether the 
DD led to an AE. The Sponsor shall review all DDs and determine and document in writing.  
 
The investigator will follow each subject who experiences an AE until the event resolves, resolves 
with sequelae, or no further improvement is expected. In the unusual circumstance that an AE has not 
resolved by the time of the subject’s completion of the study, an explanation will be entered  
 
16.3.2 Reporting of Safety related events to Sponsor 
Any SAE/ADE/SADE/USADE/DD (including serious public health threat) must be recorded 
correctly in the electronic Case Report Form (eCRF) immediately, but no later than within 3 calendar 
days (CDs)/24h for serious public health threat after the investigation site study personnel has become 
aware of its occurrence even if not all the information is available. Other than reportable events should 
be reported within 30 calendar days after the investigation site study personnel’s awareness of the 
event.  
 
Table 16-1. Timelines for events reporting by Investigators to the Sponsor 
Type of Event 
Timeline for Reporting 
ADE 
Immediately but in any event no later than 3 CDs 
SAE 
Immediately but in any event no later than 3 CDs 
SADE 
Immediately but in any event no later than 3 CDs 
USADE 
Immediately but in any event no later than 3 CDs 
All other AEs 
In a timely manner, usually within 30 CDs 
Device Deficiency  
Immediately but in any event no later than 3 CDs 
Serious Public Health threat 
Immediately but in any event no later than 24 hours 
 
 
 
Emergency Contact details for Adverse Events/Device Deficiencies/Serious health threat 
reporting: 
Sponsor: 
Moira Rossetti 
Quality Manager 
Diametros Medical srl 
Via di Terranuoba 48/5 
52025 Montevarchi -Arezzo- Italy 
qualita@diametrosmed.com 
 
+39 331 3553415 
 

 
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16.3.3 Reporting of Safety related events to Ethics Committee 
The Sponsor or designee reports to the IEC promptly any SAE which has a causal relation with the 
device, comparator, or procedure/test method or where a causal relation appears to be possible.  
 
In order to ensure prompt notification, the Sponsor may initially submit an incomplete notification. 
 
If safety and health hazards that require measures must be taken immediately during the conduct of 
the investigation, the Sponsor notifies the IEC within 2 days of these measures and the circumstances 
which made them necessary.  
 
16.3.4 Periodic Safety Reporting 
An Annual Safety Report (ASR) is submitted by the Sponsor to the IEC, yearly. The ASR contains a 
list of all SADEs and DDs and a report on their degree of seriousness, causal relationship with the 
device and procedure and on subjects’ safety.  
 
16.3.5 Other reporting 
Other reporting is done according to provisions of MD vigilance as per Art. 87-90 MDR.  
 
16.3.6 Pregnancy Reporting 
In order to ensure the safety of subjects who may become pregnant during the course of the study, 
subjects will be asked to return for all protocol-specified visits and will undergo all protocol-specified 
assessments at each follow-up visit, unless contraindicated, until the successful completion of the 24-
month follow-up visit. 
 
The Investigator will continue to follow the subject to report the outcome of the pregnancy to the 
Sponsor (i.e. live birth (full term or preterm birth), stillbirth, spontaneous abortion, and induced 
abortion. 
 
16.4 TREATMENT OF AES 
The Investigator will treat all subjects who experience an adverse event related to the device until the 
adverse event is resolved, resolved with sequelae, or no further improvement is expected. For all other 
adverse events, adverse event treatment and physician follow up will be dictated by standard of care.  
 
16.5 SECONDARY SURGICAL INTERVENTIONS (SSIs) 
The occurrence of the following SSIs will be documented for this study:  
 
A revision is a procedure that adjusts or in any way modifies or removes part of the original implant 
configuration, with or without replacement of a component. A revision may also include adjusting 
the position of the original configuration. 
 
 
A removal is a procedure where all of the original system configuration are removed with or without 
replacement. 
 
 

 
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A reoperation is any surgical procedure at the involved level(s) that does not removal, modification, 
or addition of any components to the system. 
 
 
 
A supplemental fixation is a procedure in which additional instrumentation not under study in the 
protocol is implanted (e.g., supplemental placement of a rod/screw system or a plate/screw system). 
 
16.6 SAFETY OVERSIGHT: CLINICAL EVENTS COMMITTEE (CEC) 
A clinical event committee (CEC) will be established. The CEC is an independent committee 
consisting of three (3) spine surgeons with pertinent expertise who are not participants in the study 
and who do not have any other real or potential conflicts of interest. The CEC will meet periodically 
to review all adverse events, protocol deviations, SSIs, and neurological deterioration.   
 
17. CLINICAL MONITORING 
17.1 SITE MONITORING 
The study will be monitored to ensure that it is conducted in conformance with the monitoring plan 
by the Sponsor to assess continued compliance with the protocol and to ensure and to ensure that 
applicable regulations and standards are followed. . In addition, the monitor verifies that study records 
are adequately maintained, that data are reported in a satisfactory manner with respect to timeliness, 
adequacy, and accuracy, and that the Investigator continues to have sufficient staff and facilities to 
conduct the study safely and effectively.  
 
The study may also be subject to a quality assurance audit by the Sponsor or its designees, as well as 
inspection by appropriate regulatory authorities. It is important that the Investigator and relevant 
study personnel are available during on-site monitoring visits or audits and that sufficient time is 
devoted to the process. 
 
The organization responsible for monitoring the study is: 
 
Gianni Garlatti 
General Manager 
Email: g.garlatti@diametrosmed.com 
Phone: +39 338 7845689 
In addition to ensuring adequate communication between the Investigators and the Sponsor, the 
monitor’s duties include on-site visits and review of study documents and reported data. The Monitor 
will be provided with appropriate device and protocol training prior to the study and will follow a 
Monitoring Plan for all study-related monitoring activities. 
17.2 MONITORING ACTIVITIES 
Monitoring visits include a pre-study Site Initiation Visit, periodic Interim Monitoring Visits, and a 
Close-Out Visit at the end of the site’s participation in the study. The exact details of whether visits 
will be conducted on site or remotely shall be determined on an individual site basis as detailed in the 
Clinical Monitoring Plan, 
 
Each site’s Investigator will allocate adequate time for monitoring activities. The Investigator will 
also ensure that the monitor or other compliance or quality assurance reviewer is given access to the 

 
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study-related documents and study-related facilities and has adequate space to conduct the monitoring 
visit. 
 
Monitoring visits will be documented on monitoring visit reports, and will aim to verify that:  
 
• 
Compliance with the clinical protocol and applicable regulations is being maintained 
• 
Source data is verified and signed-off upon as accurate 
• 
Subject files are accurate and complete 
• 
Subject withdrawal has been documented (if applicable) 
• 
Subject non-compliance has been documented (if applicable) 
• 
The Investigator and site staff are informed and knowledgeable of all relevant document 
updates concerning the clinical investigation 
• 
Only authorized individuals are performing study-related functions 
• 
The investigational device is being used according to the protocol and instructions for use 
• 
Adequacy of staffing and facilities 
• 
Signed and dated ICFs have been obtained from each subject 
• 
eCRFs and queries are complete 
• 
All adverse events and device deficiencies are reported to the Sponsor and the EC, as 
applicable 
• 
All other required EC reports, notifications, applications, submissions, and correspondence 
are maintained in the Investigator’s files and are accurate 
• 
Corrective and preventive actions have been implemented (if applicable) 
Monitoring activities related to eCRF, collected data, and reporting of adverse events will be done 
remotely through Smart-Trial software. 
17.3 FREQUENCY OF VISITS 
To ensure that the study is conducted in accordance with the terms of the clinical protocol, study 
monitors must visit each investigational site at routine intervals throughout the duration of the study. 
The exact frequency of visits shall be determined on an individual site basis as detailed in the Clinical 
Monitoring Plan, and shall depend upon the following factors:  
 
• 
Rate of subject enrollment 
• 
Experience of the Investigator in conducting clinical studies 
• 
Record of previous site compliance 
18. AUDITS AND INSPECTIONS 
Participation as an Investigator in this study implies acceptance of potential inspection by government 
regulatory authorities. The Investigator must also be prepared to permit study-related audits and 
inspections by the Sponsor, CRO, EC and the site’s institutional compliance and quality assurance 

 
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groups. The Investigator will ensure the capability for inspections of applicable study-related 
facilities, records, and reports. 
 
The investigators will be available to the Sponsor, EC or other regulatory authorities to discuss study 
issues as requested.  All involved parties must keep the subject data strictly confidential.  
 
In the event that an Investigator is contacted by a Regulatory Agency in relation to this clinical 
trial/investigation, the Investigator will notify the Sponsor immediately and IEC as appropriate. 
 
 
19. STATISTICAL METHODS 
19.1 ANALYSIS SETS 
The analysis data sets will be defined in a way that mirrors the Superion P140004 study. 
The primary analysis cohort for this study will be the Modified Intent-to-Treat Cohort, defined as: 
Modified Intent-to-treat patient population (mITT): The mITT patient population will include all 
patients having an anesthesia start time. Subjects with an anesthesia start time but that do not receive 
the device will be failures.  
Confirmatory analysis will be performed in the Per Protocol Cohort, defined as: Per protocol (PP) 
Population: The PP patient population will include all subjects with 12-month follow-up data and no 
major protocol deviations and subjects that failed before 12 months 
19.2 PRIMARY ENDPOINT 
Subjects will be evaluated at the 12-month follow-up for the primary endpoint. 
 
Effectiveness success will be evaluated as a two-prong composite endpoint: 
• ZCQ Responder (at least two of the three ZCQ domains) 
o ≥0.5 point improvement in physical function. 
o ≥0.5 point improvement in symptom severity 
o Mean satisfaction ≤2.5 points. 
• No secondary surgical intervention (SSI) including re-operations, revision, removals or 
supplemental fixation or clinically significant confounding treatments (i.e., epidural steroid 
injections at the index level, spinal cord stimulators or rhizotomies) through 12 months. 
 
The primary effectiveness hypothesis is that the composite success rate for the Lobster device is larger 
than the performance goal of 61.1%. A detailed description of the how the performance goal was 
calculated will be provided in the statistical analysis plan (SAP). 
 
Formally, the hypotheses to be tested are: 
 
H0:       The expected proportion of patients with composite success at Month 12 (pT) is 
less than or equal to the performance goal (PG) of 61.1%. 
 

 
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HA:      The expected proportion of patients with composite success at Month 12 (pT) is 
greater than the performance goal (PG) of 61.1%. 
 
These hypotheses may be symbolically represented as:  
  
Ho:   pT  ≤  PG = 61.1% 
HA:  pT  >  PG  = 61.1% 
 
Where pT is the composite success rate for subjects treated with the Lobster device. 
 
A one-sided normal approximation binomial test with type 1 error set to α=0.05 will be used to 
demonstrate that the investigational device meets the performance goal.  
19.3 SAMPLE SIZE ASSESSMENT 
The sample size was determined in order to have at least as many subjects as the Superion arm in 
the P140004 study, which enrolled 190 subjects, and to show superiority to the performance goal 
calculated from the results of that study. 
 
The pooled two-prong composite effectiveness at Month 12 in the P140004 study was 71.1%, so the 
reference rate is specified as 0.711. The reference margin is set to be 10%, which is the same non-
inferiority margin used in the Superion study.  The performance goal is then 71.1%-10%=61.1%. 
 
The sample size was calculated assuming the same success in the Lobster arm that was seen in the 
Superion study, 71.1%. With type 1 error set to α=0.05 and power=85%, the study would need to 
enroll 162 subjects. Allowing for 15% loss to follow-up, the study would need to enroll at least 191 
subjects.   
 
This study will enroll a minimum of 191 subjects and a maximum of 250 subjects. The final sample 
size will be justified in the SAP. 
 
Expected distribution of enrollment among site is: 50% Cagliari (main site), 25% Siena, 25% Catania. 
The enrollment cap for the main site is 105 patients. 
 
19.4 SAFETY ANALYSES 
Assessment of the safety of the investigational implant will include an evaluation of the incidence 
and severity of complications and adverse reactions associated with the treatment.  
Adverse event rates will be summarized by type of AE and for specific AEs in two ways: 1) per 
patient incidence of specific AEs and classes of AEs and 2) by event, summarizing event counts by 
visit interval over time and in accordance with FDA Guidance. Device and procedure-related events 
will be summarized by severity and relatedness. Events listings that include details such as 
relatedness, severity, onset and resolution status will be provided for all events and relevant subsets 
of events such as serious events and related events. Primary safety comparisons will be performed 
using the mITT analysis set. The summary tables will show the adverse events (in coded terms), the 
total number of events, and the number and the percentage of subjects affected in each treatment 
group (“subject wise evaluation”) and stratified by relation to device and severity.  
 

 
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The event rates observed in the Superion SSED (P140004) will be used as clinical guideposts only. 
There is no formal statistical hypothesis test on these endpoints. Please note that the primary endpoint 
captures both safety and effectiveness, and therefore these events are considered interesting but 
appropriately evaluated in this framework. Additional details regarding the safety comparisons will 
be provided in the SAP. 
 
19.5  SECONDARY EFFECTIVENESS 
The secondary endpoints are: 
• Oswestry Disability Index (ODI) 
• Visual Analogue Scale (VAS) (Back and Leg) 
• SF-12 Short Form Survey (Physical Function and Mental Health) 
• 
Patient satisfaction survey 
• 
Neurologic status  
 
Secondary continuous endpoints will be subjected to descriptive analyses including summaries over 
time and as changes over time using descriptive statistics including means, standard deviations, 
median, minimum and maximum values. Secondary categorical endpoints will be summarized over 
time using counts and percentages. In some cases, nominal 95% confidence intervals may be 
displayed for secondary endpoints. Additional details regarding the analysis of secondary endpoints 
will be provided in the SAP. 
 
19.6 MISSING DATA/SENSITIVITY ANALYSIS 
Handling of missing data will be described in the SAP. 
 
19.7 POOLING AND SUBGROUPS 
Pooling of data and description of important subgroups will be described in the SAP. 
 
20. ETHICS & REGULATORY ASPECTS 
20.1 ETHICAL CONDUCT 
The investigation will be carried out according to the CIP and with principles enunciated in the current 
version of the Declaration of Helsinki, the European Regulation on medical devices 2017/745 (MDR), 
the Norms ISO14155 and ISO14971, the ICH-guidelines of Good Clinical Practice (GCP) as 
applicable and with any applicable local or regional laws and regulations.  
 
The clinical investigational plan, informed consent, any other study specific study documents as 
required by regulations and all amendments to these study documents will be reviewed and approved 
by the apprioate regulatory authority and appropriate IEC before enrollment of any patient. EC and 
regulatory authority will receive the Annual Safety Report (ASR) and interim reports and be notified 
about investigation stop/end in agreement with local requirements. 
 
Additional requirements set by the IEC or regulatory authorities must be implemented. 

 
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20.2 REPORTING TO ETHICS COMMITTEE (IEC) AND COMPETENT AUTHORITY 
The Sponsor will submit the investigation to the EC and regulatory authority (as applicable) and 
obtain EC and regaulatory authority approval before the start of the investigation. Each PI at each 
participating investigational site ensures that approval from the EC and regulatory authority is 
obtained and filed in Investigator site file before the investigation starts. 
 
Amendments are reported accordingly as described in section 20.3. The regular or premature end of 
the investigation as well as the interruption of the investigation is reported to the IEC. The reasons 
for a premature end or an interruption have to be explained. Annual progress reports will be submitted , 
as required. A final report shall be submitted within one year after the regular end of the investigation 
and within 3 months after a premature end of the investigation.  
 
20.3 STUDY AMENDMENTS 
All changes to the protocol, that impact validity of data, scientific soundness, the rights safety, or 
welfare of the subjects, must be documented in the format of an amendment with justification 
statements in the cover letter to the EC and apprioate regulatory authorities.. All amendments must 
be submitted to the EC and regulatory authority for review and approval.  
Sponsor will inform the investigator about any relevant changes in the protocol. They will be 
documented as an amendment to the protocol which will be signed by each investigator. No changes 
can be implemented by the investigator before a fully approved amendment is available 
 
20.4 INSURANCE 
The Sponsor has issued clinical trial insurance with appropriate coverage for the continuation of the 
entire study. A copy of the certificate is filed in each investigational site file and the Sponsor file.  
 
21. DATA HANDLING AND RECORDKEEPING 
Data Management procedures will be detailed in trial specific Data Management Standard Operating 
Procedure. 
 
The handling of all data on the CRFs will be the responsibility of the Sponsor. 
 
It will be the responsibility of the investigator to ensure the accuracy of all data entered in the CRFs. 
The delegation log will identify all those personnel with responsibilities for data collection and 
handling, including those who have access to the trial database. 
 
21.1 EDC AND ECRFS 
eCRFs will be completed in an electronic data capture (EDC) system for each patient enrolled into 
the clinical study. The study staff will enter the source data onto the eCRFs, and study monitors will 
verify that the source documents match the eCRFs. Once verified, the study monitor will perform the 
monitoring approval step. 
 

 
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All procedures for the handling and analysis of data will be conducted using good clinical data 
management practices within systems meeting the Norms ISO14155 and the ICH-guidelines of Good 
Clinical Practice (GCP) as applicable for the handling, storage, and analysis of data for clinical studies. 
 
The Investigator will sign off on each patient’s casebook to attest that all data entered on the eCRFs 
are complete and accurate. All of the above signatures will be completed digitally within the EDC 
system using validated  digital signature system function. 
 
Any required data clarifications will be handled within the EDC system’s query management system. 
The EDC will be programmed to automatically place data clarification queries on missing values and 
values out of acceptable ranges. Study monitors and data managers will also be able to add data 
clarification queries to data points within the system. Study staff will have the opportunity to correct 
data and/or respond to the query for review by monitors and data managers. 
 
21.2 DATA SECURITY, ACCESS AND BACK-UP 
Data will be managed and viewed by investigators, sponsor data manager, and clinical monitor with 
different levels of privilege, according to Smart-trial software functionality and its internal security 
systems validated with ISO 14155:2020 and regulation (EU) 2016/679 . 
21.3 ELECTRONIC AND CENTRAL DATA VALIDATION  
When using electronic data handling or remote electronic trial data systems, the Sponsor or the 
Sponsor’s representative will: 
• 
Ensure and document that the electronic data processing system(s) conforms to the Sponsor 
established requirements for completeness, accuracy, reliability, and consistent intended 
performance (i.e., validation). 
• 
Maintain SOPs for using these systems. 
• 
Ensure that systems are designed to permit changes to the data in such a way that the data 
changes are documented and there is no deletion of any edited or entered data (i.e., 
maintains an audit trail). 
• 
Maintain a security system to prevent unauthorized access to the data and to uniquely 
identify individuals who access the data entry system. 
• 
Maintain a list of individuals authorized to make data changes. 
• 
Maintain adequate data backup. 
• 
Ensure that the database is properly locked before the analysis according to the sponsor 
SOP. 
• 
Ensure that patient’s privacy will be protected according to the GDPR  
• 
Ensure the database freeze/lock will be done. After cleaning process and resolution of 
queries, lock checklist will be complete and data lock and data freeze will be performed. 
Test lock will be undertaken and the final datasets will be saved by the statistician.  
• 
Esnure that any study data released shall be done according to the publication policy and in 
accordance with any local regulations.  

 
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Primary data collection based on source-documented hospital and /or clinic chart reviews will be 
performed clearly, timely, adequately, and accurately by site personnel trained on the protocol and 
eCRF completion. 
21.4 CAPTURE OF PATIENT REPORTED OUTCOMES 
There is no acquisition of directly patient-reported outcomes (PROs). 
 
Should future amendments to the study involve the use of patient-reported outcomes (PROs), the 
following will be done. PROs will be collected via web browser and the data will be transmitted 
directly to the CED.  As the data is transmitted directly to the EDC, it is considered an electronic 
source and the data is locked when it enters the EDC to ensure its security.  In cases where the web 
browser is not available (connectivity problems), paper versions of PRO forms will be used, which 
are considered sources. 
21.5 ARCHIVING OF ESSENTIAL CLINICAL INVESTIGATION DOCUMENTS  
All the documents of the investigation must be archived for a minimum of 15 years after regular or 
premature termination of the investigation. 
 
A list of the essential clinical investigation documents which should be maintained in the 
investigation site and sponsor file is given in ISO14155 Annex E. 
 
21.6 STORAGE OF BIOLOGICAL MATERIAL AND RELATED HEALTH DATA 
No biological material will be stored for further analysis.  
 
21.7 PUBLICATION AND DATA SHARING POLICY 
Data generated from the conduct of this study will be used to support an application by Diametros 
Medical as a supplement to an original Premarket Approval (PMA) from FDA. Publication of the 
results of the study will follow Diametros Medical’s Publication and Presentation Policy. 
 
The study will be registered on on a publicly accessible database (Clinicaltrials.gov). Results of the 
study, including an unanticipated early termination of the trial, will be posted to the Clinicaltrials.gov 
database at the conclusion of the study. In the event that the study is terminated early, the posting of 
these results will be completed within 30 days of completion of data analysis. 
 
21.8 PARTICIPANT AND DATA CONFIDENTIALITY 
Subject confidentiality will be maintained throughout the study in a way that ensures that data can 
always be tracked back to the source data. For this purpose, a unique subject identification code will 
be used that allows identification of all data reported for each subject without traceability back to the 
actual subject.  
 
In addition, the Principal investigator must keep a separate list of all subjects entered into the clinical 
investigation showing each subject’s name, date of birth and assigned subject number (for 
identification purposes). A Subject Identification Log will also be provided in the Investigation Site 
File to record the subject’s initials and assigned subject number. 

 
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The Principal Investigator or institution shall provide direct access to source data during and after the 
clinical investigation for monitoring, auditing, EC review and regulatory authority inspections.  
 
The duration of storage time of personal data at the investigational sites will be in accordance with 
national regulations. 
 
Information obtained in the course of executing this study, including still and motion photography, 
may be presented for regulatory, clinical or educational purposes as long as no subject is identified. 
The data collected is the property of Diametros Medical. 
 
21.9 SUBJECT RECORDS  
• 
All Source Documentation Worksheets 
• 
Supporting data (e.g., medical records, clinic charts) 
 
 
22. FUNDING AND SUPPORT 
The study is financed by Diametros Medical srl.  
 
 
 

 
Clinical Investigational Plan 
 
 
 
 
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23. REFERENCES 
1. Arnoldi CC, Brodsky AE, Cauchoix J, et al. Lumbar spinal stenosis and nerve root entrapment 
syndrome. Definition and classification. Clin Orthop 1976; 115:4-5. 
2. Treatment of Degenerative Lumbar Spinal Stenosis. Summary, Evidence Report/Technology 
Assessment: Number 32. AHRQ Publication No. 01-E047, March 2001. Agency for 
Healthcare 
Research 
and 
Quality, 
Rockville, 
MD. 
Available 
at 
HTTP://WWW.AHRQ.GOV/CLINIC/EPCSUMS/STENOSUM.HTM. 
3. Yong-Hing K, Kirkaldy-Willis WH. The pathophysiology of degenerative disease of the 
lumbar spine. Orthop Clin North Am. 1983;14:501-3. 
4. Delamarter RB, Howard M.: Lumbar spinal stenosis. Rehabilitation of the Spine, Science and 
Practice. Editors Hochschular S, Cotler H., Guyer R, Chapter 37, pp. 443-456, Mosby, 1993.  
5. Deyo RA, Rainville J, Kent DL. What can the history of physical examination tell us about 
low back pain? JAMA 1992;268:760-5. 
6. Fast A, Greenbaum M. Degenerative lumbar spinal stenosis. Phys Med Rehabil St Art Rev 
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7. Yong-Hing K, Kirkaldy-Willis WH. The pathophysiology of degenerative disease of the 
lumbar spine. Orthop Clin North Am. 1983;14:501-3. 
8. Botwin, KP, Gruber RD. Lumbar Spinal Stenosis: Anatomy and Pathogenesis. Phys Med 
Rehabil of Clin N Am 14 (2003) 1-15 
9. Delamarter RB, Howard M.: Lumbar spinal stenosis. Rehabilitation of the Spine, Science and 
Practice. Editors Hochschular S, Cotler H., Guyer R, Chapter 37, pp. 443-456, Mosby, 1993. 
10. See, Treatment of Degenerative Lumbar Spinal Stenosis. Summary, Evidence 
Report/Technology Assessment: Number 32. AHRQ Publication No. 01-E047, March 2001. 
Agency 
for 
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Quality, 
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11. North American Spine Society. Clinical Guidelines for Multidisciplinary Spine Care: 
Diagnosis and Treatment of Degenerative Lumbar Spinal Stenosis. 2011. 
12. Birkmeyer NJ. Design of the Spine Patient outcomes Research Trial (SPORT). 2002. 
13. Pearson A. Degenerative spondylolisthesis versus spinal stenosis: does a slip matter? 
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randomized and observational cohorts. 2009. 
17. Weinstein JN. Surgical Versus Nonoperative Treatment for Lumbar Spinal Stenosis Four-
Year Results of the Spine Patient Outcomes Research Trial. 2010. 

 
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18. Patil CG, Sarmiento JM, Ugiliweneza B, Mukherjee D, Nuno M, Liu JC, Walia S, Lad SP, 
Boakye M. Interspinous device versus laminectomy for lumbar spinal stenosis: a comparative 
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the lumbar spine. J Bone Joint Surg Am. 2004 Jul;86-A(7):1497-503.