Twenty-Year Radiographic Outcomes Following Single-Level Cervical Disc Arthroplasty: Results From a Prospective Randomized Controlled Trial.

STUDY DESIGN: Prospective randomized controlled trial. OBJECTIVE: Compare range of motion (ROM) and adjacent segment degeneration (ASD) following cervical disc arthroplasty (CDA) versus anterior cervical discectomy and fusion (ACDF) at 20-year follow-up. SUMMARY OF BACKGROUND DATA: Anterior cervical discectomy and fusion is the standard of treatment for single-level cervical disc degeneration causing radiculopathy. CDA is claimed to reduce shear strain, and adjacent-level ROM changes are hypothesized to hasten ASD with ACDF. MATERIALS AND METHODS: This study collected data on 47 patients randomized to ACDF or CDA. Lateral cervical spine radiographs were evaluated preoperatively, postoperatively, and at 20 years for alignment, ROM, ASD, and heterotopic ossification. RESULTS: Eighty-two percent (18/22) of CDA patients and 84% (21/25) of ACDF patients followed up at 20 years. At 20 years, total cervical (C2-C7) ROM was statistically different between the CDA and fusion groups (47.8° vs . 33.4°, P =0.005). Total cervical ROM was not significantly different between preoperative and 20-year periods following CDA (45.6° vs . 47.4°, P =0.772) or ACDF (40.6° vs . 33.0°, P =0.192). Differences in postoperative and 20-year index-level ROM following CDA were not significant (10.1° vs . 10.2°, P =0.952). Final ASD grading was statistically lower following CDA versus ACDF at both adjacent levels ( P <0.005). Twenty-year adjacent-level ossification development was increased following ACDF versus CDA ( P <0.001). Polyethylene mean thickness decreased from 9.4 mm immediately postoperatively to 9.1 mm at 20-year follow up ( P =0.013). Differences in adjacent-level ROM from preoperative to 20-year follow-up in both the ACDF and CDA groups did not meet statistical significance ( P >0.05). CONCLUSIONS: Cervical disc arthroplasty maintains index-level and total cervical ROM with very long-term follow-up. Total cervical ROM was higher at 20 years in CDA relative to ACDF. CDA results in lower rates of ASD and adjacent-level ossification development than ACDF.

20-year Clinical Outcomes of Cervical Disk Arthroplasty: A Prospective, Randomized, Controlled Trial.

STUDY DESIGN: Prospective, randomized, controlled trial. OBJECTIVE: To compare clinical outcomes of anterior cervical discectomy and fusion (ACDF) and cervical disk arthroplasty (CDA) at 20 years. SUMMARY OF BACKGROUND DATA: Concern for adjacent-level disease after ACDF prompted the development of CDA. MATERIALS AND METHODS: Forty-seven patients with single-level cervical radiculopathy were randomized to either BRYAN CDA or ACDF for a Food and Drug Administration Investigational Device Exemption trial. At 20 years, patient-reported outcomes, including visual analog scales (VAS) for neck and arm pain, neck disability index (NDI), and reoperation rates, were analyzed. RESULTS: Follow-up rate was 91.3%. Both groups showed significantly better NDI, VAS arm pain, and VAS neck pain scores at 20 years versus preoperative scores. Comparing CDA versus ACDF, there was no difference at 20 years in mean scores for NDI [11.1 (SD 14.1) vs. 19.9 (SD 17.2), P =0.087], mean VAS arm pain [0.9 (SD 2.4) vs. 2.3 (SD 2.8), P =0.095], or mean VAS neck pain [1.2 (SD 2.5) vs. 2.9 (3.3), P =0.073]. There was a significant difference between CDA versus ACDF groups in the change in VAS neck pain score between 10 and 20 years [respectively, -0.4 (SD 2.5) vs. 1.5 (SD 2.5), P =0.030]. Reoperations were reported in 41.7% of ACDF patients and 10.0% of CDA patients ( P =0.039). CONCLUSIONS: Both CDA and ACDF are effective in treating cervical radiculopathy with sustained improvement in NDI, VAS neck and VAS arm pain at 20 years. CDA demonstrates lower reoperation rates than ACDF. There were no failures of the arthroplasty device requiring reoperation at the index level. The symptomatic nonunion rate of ACDF was 4.2% at 20 years. Despite a higher reoperation rate in the CDA group versus ACDF group, there was no difference in the 20-year NDI, VAS Neck, and VAS arm pain scores.

Functional Outcomes Associated With Adjacent-level Ossification Disease 10 Years After Cervical Disc Arthroplasty or ACDF.

STUDY DESIGN: A retrospective review of a prospective, randomized control Food and Drug Administration (FDA) investigational device exemption trial comparing anterior cervical discectomy and fusion (ACDF) with Bryan cervical disc arthroplasty. OBJECTIVE: Determine the clinical significance of adjacent-level ossification disease (ALOD) on long-term functional outcomes after ACDF or arthroplasty. SUMMARY OF BACKGROUND DATA: ALOD occurs when the anterior longitudinal ligament and annulus adjacent to the index surgical level calcifies. As previously reported, ALOD happens more commonly after an arthrodesis than an arthroplasty. No investigation has previously examined 10-year clinical outcomes associated with ALOD. MATERIALS AND METHODS: Forty patients were included in the 10-year follow-up. The index level was radiographically blinded and the cephalad-adjacent level was evaluated for ALOD. These scores underwent statistical analysis to compare the 2 surgical groups (ACDF and arthroplasty) for differences in the development of ALOD at a decade follow-up. Two investigational groups, on the basis of a high or low ALOD score, then proceeded through statistical analysis to compare the functional outcomes of patients in each group. RESULTS: Statistical evaluation of ALOD findings in patients from each surgical group found a significantly higher rate of high-grade ALOD in patients who underwent cervical arthrodesis with plate fixation compared with cervical arthroplasty (68.2% vs. 11.1%, P=0.0003). Functional outcomes of patients were also assessed at the 10-year mark and outcomes in patients with either high-grade or low-grade ALOD were compared. When stratified by high versus low-grade ALOD, no significant difference was found for Neck Disability Index (NDI) (P=0.6431), VAS-arm (P=0.4497), or VAS-neck (P=0.8700) scores between groups. CONCLUSIONS: The present study suggests that there are no significant long-term functional outcome differences between patients with and without significant ALOD. Our findings suggest ALOD may be a radiographic finding that does not alter patient-reported outcomes. LEVEL OF EVIDENCE: Level III-therapeutic.

A prospective, open-label, single-arm, multi-center study of intraosseous basivertebral nerve ablation for the treatment of chronic low back pain.

PURPOSE: A prospective, single-arm, open-label study to evaluate the effectiveness of intraosseous radio frequency (RF) ablation of the basivertebral nerve (BVN) for the treatment of vertebrogenic-related chronic low back pain (CLBP) in typical spine practice settings using permissive criteria for study inclusion. METHODS: Consecutive patients with CLBP of at least 6 months duration and with Modic Type 1 or 2 vertebral endplate changes between L3 and S1 were treated with RF ablation of the BVN in up to four vertebral bodies. The primary endpoint was patient-reported change in Oswestry Disability Index (ODI) from baseline to 3 months post-procedure. Secondary outcome measures included change in visual analog scale (VAS), SF-36, EQ-5D-5L, and responder rates. RESULTS: Median age was 45 years; baseline ODI was 48.5; VAS was 6.36. Seventy-five percent (75%) of the study patients reported LBP symptoms for ≥ 5 years; 25% were actively using opioids; and 61% were previously treated with injections. Mean change in ODI at 3 months posttreatment was - 30.07 +14.52 points (p < 0.0001); mean change in VAS was - 3.50 + 2.33 (p < 0.0001). Ninety-three percent (93%) of patients achieved a ≥ 10-point improvement in ODI, and 75% reported ≥ 20-point improvement. CONCLUSIONS: Minimally invasive RF ablation of the BVN demonstrated a significant improvement in pain and function in this population of real-world patients with chronic vertebrogenic-related LBP. These slides can be retrieved under Electronic Supplementary Material.