Lightning Podiums: Spinal Gumbo - 803A

Presented by: M.F. Gornet


M.F. Gornet(1), T.H. Lanman(2), J.K. Burkus(3), S.D. Hodges(4), J.R. McConnell(5), R.F. Dryer(6), F.W. Schranck(7), A.G. Copay(7)

(1) The Orthopedic Center of St. Louis, St Louis, MO, United States
(2) California Spine Group, Century City Hospital, Los Angeles, CA, United States
(3) Wilderness Spine Services, Columbus, OH, United States
(4) Center for Sports Medicine and Orthopedics, Chattanooga Outpatient Center, Chattanooga, TN, United States
(5) Orthopedic Associates of Allentown, Allentown, PA, United States
(6) Central Texas Spine Institute, Austin, TX, United States
(7) SPIRITT Research, St Louis, MO, United States


Purpose: Two independent clinical trials have concluded that cervical disc arthroplasty (CDA) is as safe and effective as anterior cervical discectomy and fusion (ACDF) for treating symptomatic cervical disc disease (SCDD) at one and two levels. The objective of this study was to compare the safety and effectiveness at 7-year follow-up for the subjects treated with 1-level and 2-level respectively using CDA and ACDF.

Methods: This is an analysis of prospectively collected, combined data of 1 and 2-level FDA IDE clinical trials of a titanium ceramic composite cervical artificial disc. A total of 545 and 397 patients were studied in the 1-level and 2-level trials, respectively: CDA (n= 280 & 209), ACDF (n=265 & 188). The outcome measures included 84-month safety and effectiveness outcomes were compared between 1-level and 2-level CDA and ACDF, specifically: NDI, neck and arm pain (0-20 scale), SF-36 PCS, neurological status, adverse events, and secondary surgeries at index and adjacent levels. The 1-level vs 2-level comparisons were done across studies, and a propensity score method was used to adjust for potential confounding effects and adjusted means were reported.

Results: There were no preoperative differences between 1 and 2-level respectively for CDA and ACDF patients for NDI, neck and arm pain, and SF-36 PCS scores. All patient groups significantly improved for NDI, neck and arm pain, and PCS scores from preoperative to 84-month. Comparison of 1 vs 2-level CDA: there were no significant differences between 1 and 2-level CDA for NDI improvement (38.2 vs 39.0, p=0.768), neck pain (11.7 vs 12.3, p=0.374), arm pain (11.3 vs 11.0, p=0.736), SF-36 PCS (12.6 vs 14.5, p=0.220), or proportions of patients who maintained neurological status (92.8% vs 91.6%, p=0.867). The rate of secondary surgeries was numerically (but not significantly) higher for 1-than 2-level CDA at the index and adjacent levels (7.3 vs 4.2%, p=0.566) and (11.6% vs 6.5%, p=0.056) respectively. The rate of serious AEs was significantly higher for 1 than 2-level CDA (67.8% vs 56.7%, p=0.004). Comparison of 1 vs 2-level ACDF: there were no significant differences between 1 and 2-level ACDF for NDI improvement (31.1 vs 31.6, p=0.859), neck pain (9.7 vs 9.9, p=0.796), arm pain (9.9 vs 10.1, p=0.848), SF-36 PCS (10.8 vs 12.1, p=0.424), proportions of patients maintaining or improving neurological status (79.7% vs 82.1%, p=0.421), or rates of secondary surgeries at index levels (13.6% vs 14.7%, p=0.631) or adjacent levels (10.9% vs 12.5%, p=0.366). The rates of serious AEs were similar for 1 and 2-level ACDF (61.8% vs 68.2%, p=0.200) but the rates of all AEs (94.5% vs 98.2%, p< 0.001) and device-related AEs (18.9% vs. 27.7%, p=0.036) were significantly lower for 1-level than 2-level ACDF.

Conclusions: One and 2-level CDA appear to be equally safe and effective in the treatment of SCDD at 7-years. Two-level ACDF was equally effective as 1-level, but 2-level ACDF had a higher rate of device-related AEs.