P140. Posterior Lumbar Interbody Fusion Using Recombinant Human Bone Morphogenetic Protein Type 2 with Polyetheretherketone Cages

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Proceedings of the NASS 24th Annual Meeting / The Spine Journal 9 (2009) 1S-205S

post-hoc t-test was used to determine if facet degeneration at any level was more advanced in these specimens. RESULTS: We found a significant association between the trapezoidal geometry of L5 and the amount of disk degeneration at the L5/S1 level (p50.03). We also found a significant association between the trapezoidal geometry of L5 and the amount of facet arthropathy at the L4/5 level (p50.04). Additionally, the level of facet arthropathy was markedly increased at the L4/5 level as compared to any other level in all subjects with spondylolysis (p50.02). CONCLUSIONS: The findings of this study show a relationship between the L5 vertebral body trapezoidal geometry and the degree of L5/S1 disc degeneration as well as L4/5 facet degeneration. This relationship may prove useful in predicting the course of disc degeneration in patients with spondylolysis. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.

90.0% of the Control groups respectively. Radiographic results demonstrated index level motion in the Investigational group and, as expected, evidence of progressing fusion in the Control group. The most frequently treated level was C5-C6, the mean ROM at this level for the Investigational group was 8.0 degrees at baseline and 11.2 degrees at 1 year. CONCLUSIONS: Interim analysis of data from this study suggests that cervical arthroplasty with the DISCOVER Artificial Cervical Disc may offer patients with symptomatic single-level cervical degeneration another option to treat their condition. These interim results are encouraging, however, longer follow-up and a thorough statistical analysis of the data are required for a complete assessment of the safety and effectiveness of the DISCOVER disc. FDA DEVICE/DRUG STATUS: Discover Artificial Cervical Disc: Investigational/Not approved. doi: 10.1016/j.spinee.2009.08.399

doi: 10.1016/j.spinee.2009.08.398

P139. Discover Artificial Disc IDE Trial: Preliminary Results in a Multi-Center Randomized Controlled Trial for Treatment of Single-Level Cervical Disc Disease Phillip A. Tibbs, MD1, James Yue, MD2, Mark Shaffrey, MD3, Domagoj Coric, MD4; 1University of Kentucky, Lexington, KY, USA; 2Yale University, New Haven, CT, USA; 3University of Virginia, Charlottesville, VA, USA; 4Charlotte, NC, USA BACKGROUND CONTEXT: An onging IDE trial of the DISCOVER Artificial Disc comparing total disc arthroplasty to anterior cervical discectomy and fusion (ACDF) in patients with single level cervical disc disease. This study is being conducted to evaluate the safety and effectiveness of the DISCOVER disc in a well controlled clinical trial setting. PURPOSE: To present the interim one-year data from this multi-center trial. STUDY DESIGN/SETTING: Randomized, Controlled, Multicenter IDE Trial. PATIENT SAMPLE: 145 patients (85 treated with the DISCOVER disc and 60 treated with ACDF) enrolled as of February 10, 2009. OUTCOME MEASURES: Neck Disability Index (NDI), Visual Analog Scale (VAS) for pain, Neurological Status, and Range of Motion. METHODS: Entry criteria included single level cervical disc disease (C3C7) with spondylotic changes or herniation and radicular arm or shoulder pain or myeloradiculopathy. Patients were randomly assigned to treatment with either the DISCOVER Artificial Disc (Investigational), or ACDF with allograft and the SLIM-LOC Anterior Cervical Plate (Control). Patient follow-up was scheduled for 2 weeks, 3, 6, 12, and 24 months to assess outcomes measures and obtain radiographic images including AP and lateral views, flexion/extension, and lateral bend films at all visits except 2 weeks where only AP and lateral were obtained. RESULTS: This interim analysis included 31 Investigational and 11 Control subjects that had reached 1 year follow-up. Demographic characteristics (gender, age, BMI) were similar in the Investigational and Control groups. The operative time and estimated blood loss was similar in both groups as was the distribution of treated levels with C5-C6 the most frequently operatived level followed by C6-C7. Both treatment groups demonstrated improvement in both NDI and VAS compared to baseline. The mean NDI for the Investigational group improved from 52.2 pre-operative to 22.6 at one year, compared to 54.5 at pre-operative and 23.7 at one year for the Control group. The mean VAS for the Investigational group improved from 69.4 pre-operatively to 24.8 at one year, compared to 69.9 at pre-operative and 28.2 at one year for the Control group. The average NDI and VAS scores for the Investigational group compare favorably to the Control group at almost every timepoint. The neurological status at one year was improved/no change for 96.7% of the Investigational and

P140. Posterior Lumbar Interbody Fusion Using Recombinant Human Bone Morphogenetic Protein Type 2 with Polyetheretherketone Cages Charles Branch, Jr., MD1, John Eickman, MD1, Paul Geibel, MD2, Matthew Mayr, MD3, John Labiak, MD4; 1Wake Forest University Baptist Medical Center, Winston-Salem, NC, USA; 2South Texas Spinal Clinic, P.A., San Antonio, TX, USA; 3Neurosurgical Associates, Richmond, VA, USA; 4Stony Brook University Medical Center, Stony Brook, NY, USA BACKGROUND CONTEXT: The use of recombinant human bone morphogenetic protein type 2 (rhBMP-2) as a replacement for autogenous bone grafting has been extensively investigated. However limited data are available at present as to the safety and efficacy of the use of rhBMP-2 for posterior lumbar interbody fusion (PLIF). PURPOSE: To evaluate the feasibility of using a non-absorbable biocompatible polymer interbody device with rhBMP-2 in combination with spinal instrumentation for single-level degenerative lumbar disc disease. STUDY DESIGN/SETTING: Prospective, single-arm IDE trial with 30 patients enrolled at four sites. Patients treated with single-level PLIF using bilateral polyetheretherketone (PEEK) cages filled with rhBMP-2 soaked absorbable collagen sponge (ACS) in conjunction with pedicle screw fixation. PATIENT SAMPLE: Between July 2003 and October 2005, 30 patients with degenerative disc disease, which had not responded to conservative care for at least 6 months, were treated with single level PLIF using bilateral PEEK interbody cages filled with rhBMP-2/ACS. Patient demographics included 51y average age, 40% male, and 27% smokers. OUTCOME MEASURES: Fusion status was evaluated using radiographs and CT scans. Clinical outcomes were assessed using the Oswestry Disability Index (ODI), Short Form (SF)-36, back and leg pain numerical rating scales, adverse event occurrence, and patient satisfaction surveys. Additionally, serum rhBMP-2 and bovine collagen antibody screening was performed on all patients. METHODS: In a prospective manner, 30 patients underwent single-level PLIF with bilateral PEEK cages containing rhBMP-2/ACS (8.4 mg per level, typically with one 1" x 2" sponge inside and another anterior to each cage) and spinal fixation. Clinical assessments were completed preoperatively and at 1.5, 3, 6, 12, and 24 months after surgery. Two independent radiologists assessed fusion status at 6, 12, and 24 months postoperatively. Fusion success was based on the presence of bridging trabecular bone, no radiolucent lines around O50% of implant, translation !3 mm, and angulation !5 . RESULTS: At 6, 12 and 24 months, fusion was confirmed in all patients followed who had sufficient imaging data, 26/26, 27/27 and 24/24, respectively. No implant migration was observed although two patients had ongoing back pain possibly device-related. Average improvements from preoperative baseline in ODI, back pain, and leg pain scores at 24 months

Proceedings of the NASS 24th Annual Meeting / The Spine Journal 9 (2009) 1S-205S were 34.5, 54.4, 48.5 points, respectively. Overall patient satisfaction was 92.0% at 24-months with improvement perceived in 95.6% of patients. CT scans demonstrated some periannular bone formation which did not result in surgical intervention. More detailed radiological review and analysis is underway to analyze clinical and neurologic correlations. No authentic antibody response to rhBMP-2 was observed. CONCLUSIONS: In this pilot clinical study, the use of rhBMP-2 together with PEEK interbody devices for PLIF appears to result in excellent clinical outcomes and fusion results. The appearance of heterotopic bone detected on CT imaging did not appear to erode satisfactory clinical outcomes. This is consistent with findings reported by Haid et al in a prior clinical trial with threaded titanium cages and rhBMP-2(1). In light of these radiographic findings further clinical trials to determine the optimal dose of rhBMP-2 for posterior lumbar interbody applications are in development. FDA DEVICE/DRUG STATUS: InFUSE Bone Graft: Investigational/Not approved; Telamon P Implant: Investigational/Not Approved. doi: 10.1016/j.spinee.2009.08.400

P141. Tapentadol Extended Release vs. Oxycodone Controlled Release for Treating Moderate to Severe Chronic Low Back Pain: Study Discontinuations from a Randomized, Double-Blind Phase 3 Trial Mila Etropolski, MD1, Douglas Shapiro, MD, PhD1, Bernd Lange2, Akiko Okamoto1, Ilse Van Hove3, Claudia Lange2, Christine Rauschkolb, MD1; 1Johnson & Johnson Pharmaceutical Research & Development, L.L.C., Raritan, NJ, USA; 2Research and Development, Gru¨nenthal GmbH, Aachen, Germany; 3Johnson & Johnson Pharmaceutical Research & Development, Division of Janssen Pharmaceutica, N.V., Beerse, Belgium BACKGROUND CONTEXT: Tapentadol is a novel, centrally acting analgesic with 2 mechanisms of action, m-opioid receptor agonism and norepinephrine reuptake inhibition. PURPOSE: To compare study discontinuations in a placebo-controlled phase 3 trial of tapentadol extended release (ER) and oxycodone controlled release (CR) in patients with moderate to severe chronic low back pain. STUDY DESIGN/SETTING: A multicenter, randomized, double-blind, active- and placebo-controlled study using controlled, adjustable doses of tapentadol ER, oxycodone CR, and placebo. PATIENT SAMPLE: Adult patients with chronic low back pain of intensity 5 (11-point numerical rating scale [NRS]) at baseline after washout of prior analgesics. OUTCOME MEASURES: Primary efficacy endpoints were the change from baseline in average pain intensity (twice-daily pain assessments, 010 NRS) over a 12-week maintenance period (non-US) or at Week 12 of the maintenance period (US). Adverse events (AEs) and study discontinuations were assessed. METHODS: Patients were randomized 1:1:1 to receive tapentadol ER, oxycodone HCl CR, or placebo bid and titrated during an initial 3-week period to a total daily dose to achieve an optimal balance of efficacy and tolerability. During a subsequent 12-week maintenance period, patients could make additional dose adjustments as long as doses were within the allowed ranges of 100-250 mg bid for tapentadol ER and 20-50 mg bid for oxycodone HCl CR. RESULTS: A total of 965 randomized patients received at least 1 dose of study drug; 958 were evaluable for efficacy. Patients receiving tapentadol ER and oxycodone CR reported improved pain scores from baseline at Week 12 (least-squares mean difference [LSMD] vs placebo: tapentadol ER, -0.8 [P!0.001]; oxycodone CR, -0.9 [P!0.001]) and over the entire maintenance period (LSMD vs placebo: tapentadol ER, -0.7 [P!0.001]; oxycodone CR, -0.8 [P!0.001]). The entire treatment period was completed by 50.5% of patients in the placebo group, 54.1% in the tapentadol ER group, and 43.3% in the oxycodone CR group. AEs were the most common reason for treatment discontinuation in the active treatment

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groups (placebo, 4.7%, tapentadol ER, 16.7%; oxycodone, 32.3%). The majority of AEs leading to treatment discontinuation occurred during the titration period (placebo, 2.5%, tapentadol ER, 10.7%; oxycodone CR, 26.5%). In the tapentadol ER and oxycodone CR groups, respectively, the most common treatment-emergent AEs leading to discontinuation were nausea (1.6% and 11.3%), vomiting (2.5% and 7.0%), constipation (1.3% and 4.3%), dizziness (2.2% and 6.4%), and somnolence (2.8% and 5.5%). A significantly longer time to onset of treatment-emergent AEs leading to discontinuation was also observed with tapentadol ER than oxycodone CR (P!0.001). For placebo, tapentadol ER, and oxycodone CR, respectively, 59.6%, 75.5%, and 84.8% of patients experienced 1 TEAE; incidences of gastrointestinal (GI) TEAEs were nausea, 9.1%, 20.1%, and 34.5%; vomiting, 1.6%, 9.1%, and 19.2%; and constipation, 5.0%, 13.8%, and 26.8%. CONCLUSIONS: In this study, tapentadol ER (100-250 mg bid) was effective for treating moderate to severe chronic low back pain with better GI tolerability than oxycodone HCl CR (20-50 mg bid). Tapentadol ER was associated with fewer discontinuations overall and due to AEs and a longer time to onset of treatment-emergent AEs leading to discontinuation than oxycodone CR. FDA DEVICE/DRUG STATUS: Tapentadol ER: Investigational/Not approved; Oxycodone CR: Approved for this indication. doi: 10.1016/j.spinee.2009.08.401

P142. Radiostereometric Range of Motion Analysis of Prodisc Lumbar Arthroplasty at Two Year Follow-Up Mike Sun, MD1, Nathaniel Ordway1, Amir Fayyazi, MD2, Hansen Yuan, MD1, Bruce Fredrickson, MD3; 1SUNY Upstate Medical University, Syracuse, NY, USA; 2VSAS Specialists, Allentown, PA, USA; 3SUNY Upstate Medical University, Syracuse, NY, USA BACKGROUND CONTEXT: An intervertebral disc replacement may theoretically reduce or delay the incidence of adjacent level degeneration by allowing motion at the surgical level. However, many clinical studies that have examined intervertebral disc replacements have focused on clinical pain scores and less on kinematics following implantation. The limiting factor has been our inability to accurately measure spinal segment motion. With traditional cobb techniques, the measurement error often times exceed the actual motion that is being measured. Radiostereometric Analysis (RSA) is a method to accurately monitor spinal motion in three dimensions through biplanar radiographs that assesses the tantalum beads placed intraoperatively. In addition to flexion and extension, RSA is also capable of measuring lateral bending and rotation of the device with extreme precision and accuracy. PURPOSE: To accurately and precisely measure the range of motion of the spinal segments in post surgical patients after lumbar disc arthroplasty. STUDY DESIGN/SETTING: This study was designed to measure, using radiostereometric analysis (RSA), the postoperative range of motion of the spinal segment following placement of ProDisc-L interbody device (Synthes Spine, West Chester, Pennsylvania). PATIENT SAMPLE: All patients were enrolled per guidelines and indications from our IRB and IDE approved protocol for ProDisc-L. OUTCOME MEASURES: Visual Analog Scale for pain, Oswestry Disabilty Index, and Range of Motion measurements with RSA. METHODS: Twelve patients (15 discs) with a ProDisc-L intervertebral disc replacement were followed postoperatively at 0,1.5, 3, 6, 12, and 24 months. For follow-up Radiostereometric Analysis, 4 to 5 tantalum beads were inserted into the vertebrae adjacent to the ProDisc during surgery. Standing biplanar films were collected during follow-up, and the ranges of motion (ROM) (sagittal and coronal bending) of the involved vertebrae were determined by RSA. In addition, VAS for pain and Oswestry disability index surveys were also collected at each time point. RESULTS: The flexion/extension ROM with the disc replacement averaged 2.5 at 6 weeks and increased over the follow-up period to 6.6 at