A Prospective Randomized Comparison of Cervical Disc Replacement and Anterior Cervical Fusion: Combined Results from Five FDA IDE Trials from a Single Site

Proceedings of the NASS 25th Annual Meeting / The Spine Journal 10 (2010) 1S–149S (p50.178), suggesting that early disc returners actually did better than late returners. Similar results were found for neck pain, arm pain and SF-36 PCS scores. CONCLUSIONS: For both ACDFs and discs, those who returned to work had significantly better (p50.0001) outcome scores prior to returning than those who did not. This suggests that surgeons allowed patients who were doing well in both ACDF and disc groups to return to work. They continued to have better outcome measures at 24 months, suggesting that there were no adverse consequences to early return. It appears that earlier return to work in disc patients as compared to ACDF patients may be attributed to quicker and greater pain and functional improvements in those patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. doi: 10.1016/j.spinee.2010.07.119

93. A Prospective Randomized Comparison of Cervical Disc Replacement and Anterior Cervical Fusion: Combined Results from Five FDA IDE Trials from a Single Site Richard D. Guyer, MD1, Scott L. Blumenthal, MD1, Jack E. Zigler, MD1, Michael S. Hisey, MD2, Amy M. Atanasov, PhD3, Donna D. Ohnmeiss, Dr, Med3; 1Texas Back Institute, Plano, TX, USA; 2 Texas Back Institute, Denton, TX, USA; 3Texas Back Institute Research Foundation, Plano, TX, USA BACKGROUND CONTEXT: Traditionally anterior cervical fusion (ACF) has been used to treat cervical radiculopathy and neck pain. In more recent years, total disc replacement (TDR) has been developed with the goals of pain relief and motion of the operated segment. PURPOSE: The purpose of this study was to compare cervical TDR to ACF in a prospective randomized format. STUDY DESIGN/SETTING: Data were combined from five randomized, prospective FDA IDE trials conducted at a single spine clinic. PATIENT SAMPLE: The group included a total of 100 patients (66 TDR and 34 ACF). All patients were treated for pathology between C4 and C7, with the majority of cases performed at C5–6. OUTCOME MEASURES: The Neck Disability Index (NDI) was used as the primary outcome measure. Peri-operative data were also compared between the two groups. Re-operations were compared as well. METHODS: All studies had very similar inclusion/exclusion criteria and all included use of the NDI as an outcome measure. Follow-up data were collected pre-operatively and post-operatively at 6 weeks and 3, 6, 12, 24 months and annually thereafter. The mean follow-up was 26.7 months, ranging from 12 to 60 months. RESULTS: The mean blood loss, operative time, and length of hospital stay were similar in the two groups (Table 1). The mean NDI score improved significantly in both groups (p!0.01).with no significant difference between groups pre- or post-operatively. Re-operation was undertaken in one TDR patient (1.5%) which involved the implantation of a TDR at the adjacent segment for the treatment of a herniated disc. Re-operation was performed in three ACF patients (8.8%; trend for greater than TDR group 0.05!p!0.08). Two of these patients underwent posterior cervical fusion due to pseudoarthrosis of the ACF. In the third patient, disc herniation occurred at the two segments adjacent to the ACF and was treated with TDR at one level and ACF at the other. In only one patient was the study-assigned treatment aborted. This was an ACF patient whose anatomy did not allow adequate access to the disc space and re-operation was not attempted. CONCLUSIONS: This study, including patients enrolled in five different cervical TDR IDE trials at a single center found no significant differences between ACF and cervical TDR in blood loss, operative time, or length of stay. Both groups showed significant improvement in NDI scores. One patient in each group underwent re-operation at the adjacent segment; however, two additional ACF patients underwent re-operation for symptomatic

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pseudoarthrosis. This study found that cervical TDR is similar to ACF with respect to operative factors and clinical outcome. A larger sample is needed to determine if the re-operation rate is significantly less with TDR due to avoiding pseudoarthrosis. FDA DEVICE/DRUG STATUS: ProDisc-C: Approved for this indication; Kineflex-C, Mobi-C, Neodisc, Discover: Investigational/Not approved. doi: 10.1016/j.spinee.2010.07.120

94. Clinical and Radiological Outcomes of Cervical Arthroplasty at 2-Years Follow-up: Comparison between Single-level And Multilevel Procedures Thierry Dufour, MD1, Dam-Hieu Phong, MD2, Jacques Beaurain, MD3, Pierre Bernard, MD4, Jean Huppert, MD5, Eric Lioret, MD6, Jean Stecken, MD1, Jean-Paul Steib, MD7, Jean-Marc Vital, MD8, Thierry Vila, MD9, Lucie Aubourg, PhD9; 1Regional Hospital - Neurosurgery, Orleans, France; 2University Hospital - Neurosurgery, Brest, France; 3University Hospital - Neurosurgery, Dijon, France; 4Centre Aquitain Du Dos, Pessac, France; 5Clinique du Parc - Neurosurgery, Saint-Priest-en-Jarez, France; 6 University Hospital - Neurosurgery, Tours, France; 7University Hospital – Spine Surgery, Strasbourg, France; 8University Hospital, Bordeaux, France; 9LDR Medical, Troyes, France BACKGROUND CONTEXT: Cervical Disc Replacement is to date an alternative to fusion in treating single level cervical Degenerative Disc Disease (DDD). Relatively to the documented morbidity of the extensive fusion techniques, some authors advocate for the multilevel disc replacement in multilevel pathology. This remains questionable and must be evaluated. PURPOSE: To compare the safety and efficacy of cervical disc replacement with a non constrained prosthesis in multilevel versus single level DDD. STUDY DESIGN/SETTING: This is an observational, prospective and multicentric study. Patients were followed up across 10 French centres preoperatively and at 1, 3, 6, 12, and 24 months after surgery. PATIENT SAMPLE: 192 patients were analyzed: 150 patients were operated for single level cervical disc replacement and 42 patients for multilevel procedures (2 levels: 38; 3 levels: 3; 4 levels: 1). All have completed their 2 years FU evaluation. Indications were DDD leading to persistent radiculopathy and/or myelopathy between C3 and C7. OUTCOME MEASURES: Comparison between both groups was based on clinical and radiological outcomes. METHODS: The clinical assessment included usual scores: 0–100 VAS for cervical and arm pain, Neck Disability Index (NDI), and the SF-36 quality of life score. Range of motion (ROM) was measured from flexion-extension lateral views. RESULTS: There was no difference between both groups regarding demographic data. However and not surprisingly, the number of patients with the longest time since symptoms onset was more important in multilevel group than in the single level group (25.6%O4yrs and 12.5%O4yrs resp), and the surgery duration was also longer (140 mn and 85 mn resp). There was no significant difference between both groups concerning the clinical outcomes. Pain decreased significantly in both groups between pre-op and 2 years post-op: mean VAS score for cervical pain decreased from 51 to 22 (multilevel) and from 53 to 23 (single level). Mean VAS score for arm pain also decreased from 60 to 23 (multilevel) and from 68 to 25 (single level). Function was also significantly improved in both groups as illustrated by mean NDI score (Fig.). Revision surgery at the index level concerned 1 patient in the single level group (0.6%) and none in the multi-level group. Motion was well preserved in both groups after 2 years, as flexion-extension ROM averaged 9 in single level group versus 8.2 in multilevel group. 80% of the treated segments are mobile (ROMO3 ) in the single level group, vs. 77.5% in the multilevel group. Finally, after 2 years, 98% of the multilevel patients assume that they would undergo

All referenced figures and tables will be available at the Annual Meeting and will be included with the post-meeting online content.