Fusion Rate and Clinical Outcomes Following 1 or 2 Level Open Transforaminal Lumbar Interbody Fusion for Degenerative Disc Disease With Novel 3-D Printed Titanium Cages With Pedicle Screw Fixation
Phase: NA
Conditions: Intervertebral Disc Disease
Sponsor: Bone and Joint Clinic of Baton Rouge

Study Title: Fusion rate and clinical outcomes following 1 or 2 level open Transforaminal Lumbar Interbody 
Fusion for degenerative disc disease with novel 3-D printed titanium cages with pedicle screw 
fixation 
Principle Investigator: C. Chambliss Harrod, M.D. 
Clinical Trial number: NCT03018392 
Protocol Date: 26 October 2016 
 

1. 
Introduction 
1.1 Study Purpose 
To evaluate the fusion rate and clinical outcomes at 1 year of 20 patients with DDD who 
undergo a 1 or 2 level TLIF with Tritanium® PL cage and pedicle screw fixation. The proposed 
case series will build on the body of clinical and radiological evidence for this implant in TLIF 
patients. It will also provide pilot data for future studies that will compare the Tritanium ® cage to 
PEEK. 
1.2 Background 
 TLIF addresses a range of painful degenerative pathology including DDD and 
spondylolisthesis. PEEK cages are the standard of care for use in TLIF, however titanium cages 
have shown good results compared to PEEK in the literature.1   
1.3 Device 
Tritanium ® PL is an intervertebral body fusion device indicated for use with autograft and/or 
allogenic bone graft comprised of cancellous and/or corticocancellous bone graft when used as an 
adjunct to fusion in patients with degenerative disc disease (DDD) at one level or two contiguous 
levels from L2 to S1.  The Tritanium ® PL cage is a 3D manufactured titanium cage designed with 
angled serrations for bidirectional fixation and to maximize surface area for endplate contact with 
the implant. The cage is also designed to address the potential for subsidence into the endplates. 
 The Tritanium® PL Cage was cleared for marketing under 510(k) K160955 
1.4  Study Objectives 
 
  
Primary Objective  
 Assess fusion at 1 year post-operatively on CT 
 
Secondary Objectives 

 Assess pain and functional outcomes using VAS and ODI (validated 
patient reported outcomes)  
 Assess hardware placement and fusion with plain radiographs 
collected at 2 weeks, 6 months and 12 months post-op.  
 Monitor adverse events 
 
2. 
Study Hypothesis 
The Tritanium PL cage will produce satisfactory fusion rates due to its highly porous 
material designed for bone in-growth and biologic fixation. TLIF fusion rate, adverse events and 
patient reported outcomes will be qualitatively comparable to PEEK results in the literature. 
3. 
Study Methods 
3.1 Study Design  
Prospective, non-randomized (single arm) single-center study to evaluate the post-
operative radiographic and patient outcome variables of the Tritanium PL cage compared 
to literature reported outcomes for traditional PEEK cage for interbody fusion treatment of 
degenerative disc disease (DDD).  
3.2 Treatment Group 
20 patients requiring an open 1 or 2 level TLIF will make up the study population. Eligible 
patients will have lumbar (L2-S1) degenerative disc disease (may have up to grade 1 
spondylolisthesis), and/ or degenerative scoliosis. DDD is defined as back pain of discogenic 
origin with degeneration of the disc confirmed by history and radiographic studies. The DDD 
patients may also have up to Grade I spondylolisthesis at the involved level(s).  These patients 
should be skeletally mature and have six months of non-operative therapy. 
3.3 Primary Study Endpoint 

Fusion status at 1 year 
4. 
  Study Population 
4.1 Sample size 
20 patients will be enrolled in the study. Outcomes from this pilot study may be used 
to design larger controlled trials. 
4.2 Inclusion and Exclusion Criteria 
Patients must meet all of the inclusion criteria and none of the exclusion criteria in order to 
be eligible to enter the study. 
 
Inclusion Criteria 
 Subject has one or more of the following diagnoses:  
o Degenerative disc disease (DDD) at one level or two contiguous 
levels from L2 to S1. 
• 
DDD may also include up to Grade I spondylolisthesis at 
the involved level(s).  
• 
Note: DDD is defined as back pain of discogenic origin 
with degeneration of the disc confirmed by history and 
radiographic studies.  
o Degenerative scoliosis for which the Tritanium PL cage will be 
used as an adjunct to fusion.  
 Skeletally mature and  ≥ 18 years old at time of enrollment  
 Completed at least 6 months of non-operative therapy prior to surgery 
 Willing and able to sign a study specific consent and comply with the 
requirements of the protocol including follow up visits and imaging. 

 
 Exclusion Criteria 
 >2 levels requiring surgical intervention 
 Non-degenerative pathology including tumor, trauma, post-laminectomy 
kyphosis 
 Psudeoarthrosis at the index level 
 Previous fusion at the levels to be treated or at adjacent level  
 Any abnormality present which affects the normal process of bone 
remodeling including, but not limited to, severe osteoporosis involving the 
spine, bone absorption, osteopenia, primary or metastatic tumors involving 
the spine, active infection at the site or certain metabolic disorders 
affecting osteogenesis. 
 History of osteoporotic fracture 
 History of an endocrine or metabolic disorder known to affect bone and 
mineral metabolism 
 Inadequate tissue coverage over the operative site or taking medications 
that may interfere with bony/soft tissue healing including chronic steroid 
use 
 Known allergy to titanium or cobalt chrome or may be sensitive to 
materials  
 Rheumatoid arthritis or other autoimmune disease or a systemic disorder 
such as HIV, active hepatitis B or C or fibromyalgia 
 Lumbar kyphosis- lumbar lordosis < 20° 

 Degenerative scoliosis >20° OR any other pathology scoliosis (idiopathic, 
congenital, posttraumatic, iatrogenic) 
 Active systemic infection or infection at the operative site  
 Marked local inflammation 
 Any open wounds 
 Pregnant, or intends to become pregnant during the study 
 Current smokers 
 Subject is class 3 obese (BMI >40) or overweight and can produce loads 
on the spinal system which can lead to failure of the fixation of the device 
or to failure of the device itself 
 Any mental or neuromuscular disorder which would create an 
unacceptable risk of fixation failure or complications in postoperative care 
 Any neuromuscular deficit which places an unsafe load level on the device 
during the healing period 
 Any other medical or surgical condition which would preclude the 
potential benefit of spinal implant surgery, such as the presence of tumors, 
congenital abnormalities, elevation of sedimentation rate unexplained by 
other diseases, elevation of white blood cell count (WBC), or marked left 
shift in the WBC differential count. 
 Any condition of senility, mental illness, or substance abuse. 
 Involved in current spinal litigation that may interfere or influence patient 
self-assessment of function and pain 

 Physical or mental condition that may interfere or influence patient self-
assessment of function and pain. 
 Incarcerated at the time of study enrollment 
4.3      Study Duration 
Study subjects will be expected to participate in this study for 12 months following 
surgery, with follow-up evaluations at initial post-op (2 weeks), 3 months, 6 months, and 
12 months. 
5. 
Study Objectives/Outcomes 
5.1 Primary Study Objective 
Evaluate fusion status at 1 year (12 months) 
 
Radiographic Assessment of Fusion  
Radiographic assessments by CT scan and AP/ lateral x-rays at the 12 month 
visits include overall assessment of fusion. Fusion will be graded by the Principle 
Investigator taking into account signs such as:  
• Bony Bridging  
• Radiolucency  
• Development of Pseudoarthrosis  
5.2 Primary Safety Objectives 
•  
The evaluation of all adverse events including device related, procedure 
related and additional serious adverse events.  
•  
Evaluation and reporting of additional surgical intervention at the operative 
site including revision and/or device removal  

All adverse events will be documented on a continuous basis and reviewed by the 
Bone and Joint Clinical Research Staff. Information regarding all device failures including 
implant breakage, subsidence, migration, or expulsion will be captured.  
5.3 Secondary Objectives  
Secondary objectives are expected to further define the patient outcomes for 
effectiveness of the surgery and device in this population. 
5.3.1 Oswestry Disability Index  
The Oswestry Disability Index (ODI) is the most commonly used outcome 
measure in patients with low back pain. It has been extensively tested, showed good 
psychometric properties, and applicable in a wide variety of settings. This validated 
patient-reported outcome measure is a 10 item questionnaire that evaluates disability 
and functional impairment associated with back problems. A total ODI score is 
determined by adding the scores of the individual questions and dividing that total by 
the maximum possible score to yield a percentage. Therefore, the ODI score ranges 
from 0% to 100%. A higher score corresponds to a greater disability. 
5.3.2 Visual Analog Scale  
The severity of back and leg pain will each be evaluated in all study 
subjects using a 10 cm visual analog scale (VAS). 
6. 
Study Enrollment and Follow Up Visits 
6.1  Screening visit 
Consecutive patients who potentially meet the inclusion/exclusion criteria for the 
study will be screened for eligibility. Patients who agree to participate in the study will 
sign an IRB approved Informed Consent form. Consenting patients who meet the 
inclusion/exclusion criteria will complete preoperative demographics and subject 

questionnaires (ODI and VAS). Patients will have recent (appropriate for surgical 
planning by the PI) AP, Lateral and Flex/Ext x-rays. 
6.2 Follow Up Visits 
Patients will return to clinic to complete subject questionnaires (ODI and VAS) at 2 
weeks, 3 months, 6 months, and 12 months postoperatively. Plain radiographs (AP and 
Lateral views) will be obtained at 2 weeks, 6 months and 12 months. A CT scan will also 
be obtained at 12 months. 
 
7. 
Hospitalization/Surgical Technique/Discharge 
Subjects will be admitted to the hospital according to the Principle Investigator’s standard 
for an instrumented posterolateral fusion in conjunction with a TLIF surgery. Prophylactic 
antibiotics, preoperative planning, patient positioning and anesthesia will be carried out in 
accordance with the institution’s and Investigator’s standard of care.  
7.1   
 Surgical Approach 
The surgeon performs a midline incision and standard posterior exposure to 
decorticate the transverse processes bilaterally to accommodate graft for the posterior 
fusion. The spinous processes and interspinous ligaments can usually be left intact, 
which minimizes epidural scarring and provides a larger surface area for the posterior 
fusion. 
After exposure, pedicle screws are placed bilaterally. Fluoroscopy or other 
strategies may be used to aid in proper screw positioning. Distraction may then be 
performed using the surgeon’s preferred method to open the posterior portion of the 
disc space, if needed.  

7.2   Transforaminal Lumbar Interbody Fusion (TLIF)  
For the TLIF procedure, access to the disc space is gained via a triangular 
working window. The window is formed by the traversing nerve root and thecal sac 
on the medial side, the exiting nerve root from the proximal vertebral level on the 
lateral side, and the superior aspect of the pedicle of the distal vertebra forms the base 
of the triangle. The surgeon performs a laminotomy, laminectomy and/or facetectomy 
(partial or total) along with removal of the ligamentum flavum to provide access to 
the disc space. Care should be taken to preserve the facets as much as possible and 
remove only enough bone as needed to provide access for introduction of the 
interbody spacer and to decompress and mobilize the nerve root as necessary. If 
decompression of the contralateral side of the spinal canal is required, the TLIF 
procedure can be modified to include a central laminectomy.  
After exposure of the posterior aspect of the disc, an incision is made in the 
annulus through which the discectomy and endplate preparation are performed. 
Endplate preparation consists of removal of the cartilaginous endplate down to 
bleeding bone. The Tritanium PL interbody cage is then introduced.  
Once the interbody implant is in place and bone graft added to the disc space, 
distraction is released and compression is applied to the pedicle screw to load the 
anterior implant and restore lordosis to the spine.  
7.3 Surgical Close and Recovery 
 Standard procedures and precautions are to be followed for closure of the 
surgical incision and postoperative recovery. The patient is typically mobilized out of 
bed the day after surgery; bracing is not required but can be used according to 

surgeon preference. The subject may be instructed to return to normal activity at the 
discretion of the Investigator.  
8. 
Data Collection 
All data collected for the study will be maintained on Case Report Forms and stored in a 
secure location at the Bone and Joint Clinic of Baton Rouge. All data will also be stored in 
discreet fields in a database.  
8.1 Baseline Data – A preoperative history and physical to include demographics and 
diagnosis data will be taken at the screening/baseline visit after Informed Consent is 
obtained. Baseline data will include: 
 
Date of Visit 
 
DOB 
 
Gender 
 
Height and Weight 
 
Tobacco Use 
 
Diagnosis 
 
Affected levels 
 
AP, Lateral, and Flex/EXT x-rays 
 
Back and Leg VAS 
 
ODI 
8.2 Surgery Data.  
 
Implanted System Details 
 
Surgery Detail/Concomitant Procedures  
 
Surgery Time (initial incision to closure) 

 
Perioperative Antibiotic Use  
 
Estimated Blood Loss 
 
Intra-operative complications, if any  
8.3 Follow up data 
 
AP, Lateral x-rays (2 weeks, 6 weeks and 12 months) 
 
Back and Leg VAS (2 weeks,  6 weeks, 3 months and 12 months) 
 
ODI (2 weeks, 6 weeks, 3 months and 12 months) 
 
CT (12 months) 
 
Adverse Events (if applicable) 
9. 
Benefits and Risks 
9.1 Potential Benefits 
There is no guarantee that the subject will experience any immediate or direct 
benefits from the surgery, the Tritanium ® device or from taking part in this study. 
9.2 Risks 
Potential risks include those associated with any spinal surgery resulting in neurological, 
cardiovascular, respiratory, gastrointestinal compromise, or death. 
9.3 Mitigation of Risks 
Operative and acute periprocedural risks for the patients enrolled in this study are mitigated by 
the operating orthopedic spine surgeon being trained and experienced in the proper surgical 
technique to perform the surgery and to implant the respective device. Long-term risks such as 
device failure or pseudoarthrosis are mitigated by proper patient selection and by following 
accepted standard of care in this population for spinal fusion surgery. 
10. 
Statistical Methods 

The purpose of this study is to build upon the available data for the Tritanium implant in 
this on-label population. Descriptive statistics will be used to summarize demographics and 
baseline and surgical variables.  
Change in in VAS and ODI will be determined and the percentage of patients exceeding 
the MCIC (minimally clinical important change) will be reported for each outcome. The 
MCIC to be used for each patient reported outcome are derived from Parker, et al, J 
Neurosurgery Spine, 2011.2 
 VAS – Leg pain- 2.8  
 VAS – Back Pain- 2.1 
 ODI – 14.9 
The fusion rate will be reported and qualitatively compared to TLIF fusion rates in the literature.3  
11. 
References 
1.  
Nemoto O, Asazuma T, Yato Y, Imabayashi H, Yasuoka H, Fujikawa A. Comparison of fusion 
rates following transforaminal lumbar interbody fusion using polyetheretherketone cages or 
titanium cages with transpedicular instrumentation. Eur. Spine J. 2014;23(10):2150-5. 
doi:10.1007/s00586-014-3466-9. 
2.  
Parker SL, Adogwa O, Paul AR, et al. Utility of minimum clinically important difference in 
assessing pain, disability, and health state after transforaminal lumbar interbody fusion for 
degenerative lumbar spondylolisthesis. J. Neurosurg. Spine 2011:1-7. 
doi:10.3171/2010.12.SPINE10472. 
3.  
Khan NR, Clark AJ, Lee SL, Venable GT, Rossi NB, Foley KT. Surgical Outcomes for Minimally 
Invasive vs Open Transforaminal Lumbar Interbody Fusion. Neurosurgery 2015;77(6):847-874. 
doi:10.1227/NEU.0000000000000913.