A Prospective Clinical Pilot Study Of Fusion Rates Using Spira™-C Titanium 3-D Printed Interbody Device For Anterior Cervical Discectomy And Fusion
Phase: NA
Conditions: Cervical Radiculopathy, Cervical Disc Disease
Sponsor: Corewell Health East

IRB NUMBER: 2018-378
IRB APPROVAL DATE: 12/18/2018
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Beaumont Health – Orthopaedic Surgery Research
A PROSPECTIVE CLINICAL PILOT STUDY OF FUSION RATES USING SPIRA™-C 
TITANIUM 3-D PRINTED INTERBODY DEVICE FOR ANTERIOR CERVICAL DISCECTOMY 
AND FUSION
Protocol Version: v. 1.2 Date: 12.12.18
Department of Orthopaedic Surgery - Beaumont Health System
Principal Investigator: Jad Khalil, MD
Jad G. Khalil, M.D. (First Author)
Department of Orthopaedic Surgery
William Beaumont Hospital
3535 West 13 Mile Rd., Suite 744
Royal Oak, MI  48073
jadkhalil@gmail.com
Jeffrey S. Fischgrund, M.D.
Department of Orthopaedic Surgery
William Beaumont Hospital
3535 West 13 Mile Rd., Suite 744
Royal Oak, MI  48073
jsfischgrund37@gmail.com
Kevin C. Baker, Ph.D.
Department of Orthopaedic Surgery
William Beaumont Hospital
3535 West 13 Mile Rd., Suite 744
Royal Oak, MI  48073
Kevin.Baker@beaumont.org
Lisa L. Motowski, BSN
Department of Orthopaedic Surgery
William Beaumont Hospital
3535 West 13 Mile Rd., Suite 744
Royal Oak, MI  48073
Lisa.motowski@beaumont.org

IRB NUMBER: 2018-378
IRB APPROVAL DATE: 12/18/2018
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A PROSPECTIVE CLINICAL PILOT STUDY OF FUSION RATES USING SPIRA™-C 
TITANIUM 3-D PRINTED INTERBODY DEVICE FOR ANTERIOR CERVICAL DISCECTOMY 
AND FUSION
INTRODUCTION/BACKGROUND
Anterior cervical discectomy and fusion surgery (ACDF) is a common procedure 
performed by spine surgeons for degenerative disc disease and spinal stenosis of the 
cervical spine.  Typically, patients present with neck pain associated with radiculopathy or 
myelopathy; ACDF surgery is the treatment of choice once conservative, non-operative 
therapies have been exhausted.  During ACDF surgery, a discectomy is performed and an 
interbody spacer or cage is implanted in the disc space to facilitate arthrodesis and 
maintain stability and intervertebral height; this is further stabilized with plate and screws 
fixated at the intended level.  There are many material and design options for interbody 
cages ranging from metal, plastic, composite, and allograft to enhance bone growth and 
optimize fusion.  Polyetheretherketone (PEEK) and titanium are two materials commonly 
used to manufacture interbody cages and both are routinely utilized in ACDF surgery. 1 
Although both PEEK and titanium cages are biocompatible with similar fusion rates (88% 
vs. 93% respectively3, 100% both cages8, and 100% vs. 86.5% respectively6), PEEK cages 
offer a modulus of elasticity similar to cortical bone, which can contribute to a lower 
subsidence rate by allocating stress and load.2 However, given the smooth surface and 
hydrophobic properties of PEEK, it may inhibit cell adhesion and osseointegration.1 
Titanium cages offer durability and enhanced osseointegration but a higher modulus 
elasticity.4  There are other factors that can influence the performance of a cage aside from 
material, including endplate preparation, bone density, cage placement, and cage design9 
Ideally, an interbody cage should possess biomechanical stability and biocompatibility with 
a low incidence of subsidence and a high potential for osseointegration while maintaining 
intervertebral height and alignment.  In order to obtain some of these features there have 
been modifications in shape and structure of cages as well as the material surface (i.e. 
porous, roughened, or osteoconductive treated surfaces) to promote osseointegration.10 A 
recent technology growing in spinal surgery is the use of 3D printed titanium cages.  3D 
printing allows for the fabrication of atypical cage designs that traditionally could not have 
been manufactured.1 These designs may include a more open and intricate structure to 
allow for significant bone packing and bone ingrowth.  Another feature of 3D printing is the 
ability to modify the material surface to create an osteoconductive foundation.1 3D printed 
cages can incorporate these biomechanical factors to maximize the potential for fusion and 
stable fixation.  In a preclinical study by McGilvray et al (2018), it was found that there was 
a significantly greater total bone volume within the 3D porous titanium device compared to 
PEEK at 8-weeks and 16-weeks as demonstrated on micro-CT as well as a significant 
decrease in flexion-extension range of motion for the 3D porous titanium device.1 There are 
prior studies comparing traditionally manufactured titanium alloy cages to PEEK as cited in 
the previously mentioned fusion rates.3,6,8  In this pilot study proposal, a prospective, 
single-arm treatment group using a 3D printed porous titanium alloy cage (Spira™-C; 
Camber Spine Technologies, Wayne PA) will be compared to historical data based on 
literature review of fusion rates and patient reported outcomes of PEEK interbody cages .

IRB NUMBER: 2018-378
IRB APPROVAL DATE: 12/18/2018
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OBJECTIVE
The objective of this study is to perform a prospective, single-arm clinical evaluation 
utilizing the Spira™-C 3-D printed titanium interbody device for treatment of degenerative 
disc disease and spinal stenosis of the cervical spine to evaluate fusion status and patient 
reported outcomes.  The primary objective is fusion status; this will be measured using 
dynamic (flexion and extension) X-rays and CT scan at 12 months.  Secondary objectives 
include evaluation of patient reported outcomes, VAS score (pain), NDI (neck disability 
index; pain and function), SF-36 (quality of life), and EAT-10 (dysphagia). Also, radiographs 
will be evaluated for the occurrence of device-related adverse events or complications, 
such as revision surgery at the index level, subsidence, migration, and failure or loosening 
of the interbody device.   Neurological motor and sensory evaluations will be followed for 
improvement or worsening over the course of the study.  Data collected from subjects 
treated with the Spira™-C Interbody Device will be compared to historical data based on 
literature review of fusion rates and patient reported outcomes of traditional PEEK 
interbody cages.
DESCRIPTION OF SPIRA™-C OPEN MATRIX CERVICAL INTERBODY DEVICE
The Spira™-C Open Matrix Cervical Interbody Device, manufactured by Camber 
Spine Technologies, was 510(k) cleared by the FDA on October 17, 2017.  The Spira™-C 
device is a 3-D printed titanium alloy cage designed with open spiral supports to allow for a 
hollow chamber to facilitate the packing of bone graft to optimize fusion.  Spira™-C is 
indicated for use at one or two contiguous levels from C3-C7 for degenerative disc disease 
(DDD) with up to grade I spondylolisthesis.  It is intended to be used with a supplementary 
FDA-cleared plate fixation system.  Spira™-C must be used with autograft or cancellous or 
cortico-cancellous allograft. 
METHODOLOGY
Study Design
This is a post-market, single-arm, prospective clinical study to evaluate fusion status 
and patient reported outcomes using the Spira-C titanium interbody cage for degenerative 
disc disease where single-level ACDF surgery is indicated.  The treatment group will consist 
of 40 subjects treated with the Spira™-C Interbody Device at one level.  Patients with a 
diagnosis of cervical degenerative disc disease and/or spinal stenosis, radiculopathy or 
myelopathy and planning to undergo a 1-level ACDF surgery between C3-C7 will be 
screened.  If the subject meets all of the inclusion criteria and none of the exclusion criteria, 
the patient will be approached regarding study participation by the surgeon or study 
coordinator.  If the subject wishes to participate, the study coordinator will initiate the 
consent process.  Once the consent process has been completed and the subject has signed 
an IRB approved informed consent form the medical history, cervical spine examination 
(motor/sensory), and baseline subject questionnaires (VAS, NDI, SF-36, and EAT-10) will 
be collected.  Once the ACDF surgery has taken place as planned; data will be regarding the 
surgery performed, operative time, bone graft used, plate and screw fixation system used, 

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length of stay, and adverse events or complications related to the procedure, device, or 
cervical spine.  
Subjects will be followed up postoperatively at 6-weeks, 3-months, 6-months, and 
12-months as per standard of care, at the private practice or clinic.  During these visits, 
subjects will complete the questionnaires, cervical spine (motor/sensory) examination 
completed by the investigator, and cervical spine x-rays done per standard of care. Adverse 
events related to the device and/or procedure and/or cervical spine will be assessed at 
each visit.
Radiographic assessments will be performed at all postoperative visits; fusion status 
will be measured using dynamic (flexion and extension) X-rays and CT scan at 12 months.  
Fusion status at 12-months will be evaluated by an independent spine surgeon.   
Radiographs, including a cervical spine CT at 12-months, will also be utilized to assess for 
device-related complications, including implant failure.  Any clinically significant 
complications related to the device will be recorded as an adverse event.  Specifically, 
subsidence, migration, and loosening of the device that result in non-union or 
pseudoarthrosis and/or clinically significant neurological symptomology will be 
considered a device failure and reported as an adverse event.  Also, any incidental findings 
on the CT scan will be discussed with patient and a referral to primary care physician will 
be made for further evaluation if necessary.
Data collected from subjects treated with the Spira™-C Interbody Device will be 
compared to historical data based on literature review of PEEK cage fusion rates and 
patient reported outcomes.
This study design reflects the current standard of care for cervical degenerative disc 
disease and spinal stenosis with symptoms of radiculopathy or myelopathy.  Anterior 
cervical discectomy and fusion using an interbody device with plate and screw fixation is 
the treatment of choice after conservative therapies (non-surgical, i.e., physical therapy, 
epidural steroid injections, pain medications) have been exhausted.  
Study Population – Inclusion/Exclusion Criteria
Patients scheduled to undergo a primary single-level ACDF surgery between C3-C7 
will be approached about potential study participation.  If the patient wishes to proceed 
with study participation, the study coordinator will perform the informed consent process.  
After the consent process has been completed and study details have been discussed, the 
subject will be further screened for eligibility and given the subject questionnaires to 
complete.  
Inclusion Criteria
1. ≥ 18 years of age and skeletally mature
2. Able to provide consent
3. Undergoing a primary, single-level ACDF between C3-C7
4. Diagnosis of symptomatic degenerative disc disease 
5. Neck pain and/or radicular symptoms with a baseline Visual Analog Scale 
score of ≥ 4cm (0-10cm scale)
6. Baseline Neck Disability Index score of ≥ 20 

IRB NUMBER: 2018-378
IRB APPROVAL DATE: 12/18/2018
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7. Attempted at least 6-weeks of conservative non-operative treatment 
Exclusion Criteria
1. Any prior history of cervical fusion
2. Requires cervical fusion of more than one level
3. Acute cervical spine trauma requiring immediate intervention
4. BMI > 40
5. Active systemic bacterial or fungal infection or infection at the operative site
6. History of vertebral fracture or osteoporotic fracture
7. Current treatment with chemotherapy, radiation, immunosuppression or 
chronic steroid therapy
8.  History of osteoporosis, osteopenia, or osteomalacia that would 
contraindicate spinal surgery
9. Psychological or physical condition in the opinion of the investigator that 
would interfere with completing study participation including completion of 
patient reported outcomes
10. History of neurological condition in the opinion of the investigator that may 
affect cervical spine function and pain assessments
11. Subjects with a history of cancer must be disease free for at least 3 years; 
with the exception of squamous cell skin carcinoma
12. Pregnant, or plans on becoming pregnant
13.  History of allergy to titanium 
Intervention
The intervention will consist of 40 patients undergoing an anterior cervical 
discectomy and fusion surgery where the Spira™-C Open Matrix Cervical Interbody cage 
with autograft and allograft will be utilized for interbody fusion at a single-level between 
C3-C7.
Statistical Analysis
The primary objective of this pilot study is to evaluate fusion status using the 
Spira™-C titanium interbody device at the 12-months postoperative time point.  Results 
obtained in this study will be compared to historical data based on literature review.   
Based on previous literature review, a sample size of 40 patients was determined to be 
adequate for this study.  The Wilson Score method was used to calculate two-sided 
confidence intervals for a single proportion (fusion rate) from .70 to 1.00.   A sample size of 
40 produces a two-sided 95% confidence interval with a width equal to 0.274 when the 
sample proportion is 0.70 and 0.088 when the sample proportion is 1.00.  The intervals 
may be wider based on dropout rate at the 12-month endpoint.  Due to the pilot nature of 
this study, the dropout rate will help to provide an estimate for similar future studies. 
 
Data and Safety Monitoring

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IRB APPROVAL DATE: 12/18/2018
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The PI and study team (including sub-investigators, clinical research manager) will 
be responsible for data and safety monitoring.  All adverse events will be reviewed to 
determine relatedness to the product and reported to sponsor as necessary (if related to 
product and unanticipated according to risk profile).  The data will be reviewed for 
maintenance of confidentiality and integrity as well as the data collection process.  The data 
and safety review will take place every six months from the date of the first patient 
enrolled into the study or after ten patients have been enrolled whichever comes first.
Adverse Events
Relevant adverse events (those related to the study device, the surgical procedure, 
or cervical spine) or complications will be recorded in this study; including revision 
surgery at the index level, pseudoarthrosis, subsidence, migration, and failure or loosening 
of the device. Subsidence, migration, or loosening of the device that result in non-union or 
pseudoarthrosis and/or clinically significant neurological symptomology will be 
considered a device failure and reported as an adverse event.   Any unanticipated serious 
adverse events related to the device will be reported to the IRB as well as the 
manufacturer.   Per Medical Device Reporting (MDR) regulation (21 CFR 803), 
manufacturers and facilities are required to report to the FDA when it is known that any of 
their devices have caused or contributed to a death or serious injury.
Protocol Deviations
    The investigators are responsible for documenting all protocol deviations, including an 
explanation for why the deviation occurred.  All protocol deviations will be recorded and 
submitted to the IRB per policy.
OUTCOMES
Primary Endpoint

Successful cervical spinal fusion as measured by dynamic (flexion and extension) X-
rays and CT scan at 12 months as evidence by the following three criteria: bony 
bridging, no development of pseudoarthrosis, and no presence of radiolucency  
Secondary Endpoints

Improvement in patient-reported outcomes as measured by VAS (≥2-point 
improvement), NDI (≥ 15-point improvement), SF-36 (≥ 15-point improvement and 
EAT-10 (score of < 3) from baseline to 12-months.

No occurrence of adverse events or complications related to the device by month 
12; including revision surgery at the index level, subsidence, migration, and failure 
or loosening of the interbody device.  Subsidence, migration, and failure that results 

IRB NUMBER: 2018-378
IRB APPROVAL DATE: 12/18/2018
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in non-union or pseudoarthrosis and/or clinically significant neurological 
symptomology will be considered a device failure and reported as an adverse event.

No new or worsening neurological (motor and sensory of the cervical spine) deficit 
as compared to baseline through 12-months.  
SUBJECT SCREENING AND ENROLLMENT
Patients scheduled to undergo a primary single-level ACDF surgery between C3-C7 
will be approached about potential study participation.  If the patient wishes to proceed 
with study participation, the study coordinator will perform the informed consent process.  
After the consent process has been completed and study details have been discussed, the 
subject will be further screened for eligibility and given the subject questionnaires to 
complete.  
Screen Failures
If the subject does not meet all inclusion criteria or meets one of the exclusion 
criteria after signing consent, then the subject will be considered a screen failure and 
therefore, not enrolled into the study.  The subject will also be considered a screen failure 
and not enrolled in the study if there is a change in surgical treatment based on the 
surgeon’s observations and best practice intraoperatively.  
Withdrawals
A subject who withdraws consent prior to study completion will be removed from 
the study and no longer followed.  The surgery, instrumentation, and bone grafts are FDA 
approved and cleared and considered standard of care.  The subjects may follow-up as 
needed and per standard of care at their own discretion if they decide to no longer 
participate in the study.   The reasons for voluntary withdrawal or discontinuation of study 
subjects will be documented. If during the course of the clinical study, a study subject is 
non-responsive to attempts to schedule follow-up visits, communication methods such as 
phone calls, emails, mail, or other means as appropriate in an attempt schedule an 
appointment or determine if the subject has moved, died, or otherwise become lost to 
follow-up. 

IRB NUMBER: 2018-378
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Study Synopsis
Sponsor
Camber Spine Technologies
418 E. Lancaster Ave.
Wayne, PA 19087
Protocol Version
Version 1.2 Date: 11.01.18
Study Title
A PROSPECTIVE CLINCAL PILOT STUDY OF FUSION RATES USING SPIRA™-C 
TITANIUM 3D PRINTED INTERBODY DEVICE FOR ANTERIOR CERVICAL 
DISCECTOMY AND FUSION (ACDF)
Site/ PI
Beaumont Health – Royal Oak (William Beaumont Hospital)
Principal Investigator: Jad Khalil, MD 
Study Design
Post-market, single-arm, prospective clinical pilot outcomes study
Study Duration
Approximately 3 years (enrollment of first subject to the last follow-up 
visit)
Enrollment 
Number
Total: 40  
Treatment: 40 Spira™-C Open Matrix Titanium interbody cage (on-label 
use)
                                
Treatment Arm
40 patients undergoing an anterior cervical discectomy and fusion 
surgery where the Spira™-C Open Matrix Cervical Interbody cage with 
autograft and allograft will be utilized on-label for interbody fusion at a 
single-level between C3-C7.
Data collected from subjects treated with the Spira™-C Interbody Device 
will be compared to historical data based on literature review of fusion 
rates and patient reported outcomes of traditional PEEK interbody 
cages.
Study Objectives
Primary Objective:

To evaluate fusion status using the Spira™-C titanium interbody 
device for treatment of degenerative disc disease of the cervical 
spine at a single-level between C3-C7 at 12-months. 
Secondary Objectives:

To evaluate VAS, ODI, SF-36 and EAT-10 scores postoperatively 
compared to baseline/preoperative

To evaluate the occurrence of device-related or procedure 
related adverse events or complications including subsidence 
and pseudoarthrosis.

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Study Endpoints
Primary Endpoint:

Successful cervical spinal fusion as measured by dynamic 
(flexion and extension) X-rays and CT scan at 12 months and as 
evidenced by the following three criteria: bony bridging, no 
development of pseudoarthrosis, and no presence of 
radiolucency . 
Secondary Endpoints:

Improvement in patient-reported outcomes as measured by VAS 
(≥2-point improvement), NDI (≥ 15-point improvement), SF-36 
(≥ 15-point improvement and EAT-10 (score of < 3) from 
baseline to 12-months.

No occurrence of adverse events related to the device by month 
12; including revision surgery at the index level, subsidence, 
migration, and failure or loosening of the interbody device. 
Subsidence, migration, and loosening of the device that result in 
non-union or pseudoarthrosis and/or clinically significant 
neurological symptomology will be considered a device failure 
and reported as an adverse event.

No new or worsening neurological (motor and sensory of the 
cervical spine) deficit as compared to baseline through 12-
months. 
Inclusion Criteria
A subject may be included if the following criteria are met:
1.
≥18 years of age and skeletally mature
2.
Able to provide consent
3.
Undergoing a primary, single-level ACDF between C3-C7 
4.
Diagnosis of symptomatic degenerative disc disease
5.
Neck pain and/or radicular symptoms with a baseline 
Visual Analog Scale score of ≥ 4 (0-10cm scale) for neck 
or arm pain
6.
Baseline Neck Disability score ≥ 20
7.
Attempted at least 6-weeks of conservative non-
operative treatment 
Exclusion Criteria
A subject will be excluded if any of the following criteria are met:
1.
Any prior cervical fusion surgery 
2.
Requires cervical fusion of greater than one level
3.
Acute cervical spine trauma requiring immediate 
intervention
4.
BMI > 40
5.
Active systemic bacterial or fungal infection or infection 
at operative site
6.
History of an osteoporotic fracture and/or vertebral 
body fracture
7.
Current treatment with chemotherapy, radiation, 
immunosuppression or chronic steroid therapy

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8.
History of osteoporosis, osteopenia, or osteomalacia that 
would contraindicate spinal surgery
9.
Psychological or physical condition in the opinion of the 
investigator that would interfere with study 
participation, including completion of patient reported 
outcomes
10. History of neurological condition in the opinion of the 
investigator that may affect cervical spine function and 
pain assessments
11. Subjects with a history of cancer must be disease free for 
at least 3 years; with the exception of squamous cell skin 
carcinoma
12. Pregnant, or plans on becoming pregnant
13. History of allergy to titanium
Study Schedule of 
Events 
All subjects who sign an IRB approved consent form are considered in 
active screening to determine eligibility.  Once a subject is consented, the 
following visits will take place:
Baseline Visit:

Medical history

Cervical Spine Exam

Demographics

VAS, NDI, SF-36, EAT 10 questionnaires

Cervical spine x-rays AP/lateral, flexion/extension or as done 
per standard of care
Surgical Visit (≤ 60 days of baseline visit):

Surgery performed

Amount of Bone Graft, both local bone autograft/allograft used 

Cervical plate and screw fixation system used

Adverse Events/Complications
6-week Visit (± 2 weeks):

VAS, NDI, SF-36, EAT 10

Cervical Spine Exam

Cervical AP/Lateral x-rays

Adverse Events
3-month Visit (± 3 weeks):

VAS, NDI, SF-36, EAT 10, patient satisfaction questionnaires

Cervical Spine Exam

Cervical AP/Lateral and flexion/extension x-rays

Adverse Events
6-month Visit (± 1 month):

VAS, NDI, SF-36, EAT 10

Cervical Spine Exam

Cervical AP/Lateral and flexion/extension x-rays

Adverse Events

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12-month Visit (± 2 months):

VAS, NDI, SF-36, EAT 10

Cervical Spine Exam

Cervical AP/Lateral and flexion/extension x-rays

CT scan of the cervical spine without contrast

Adverse Events

IRB NUMBER: 2018-378
IRB APPROVAL DATE: 12/18/2018
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