Background: Adjacent-segment disease (ASD) is a well-described long-term complication after lumbar fusion. There is a lack of consensus about the risk factors for development of ASD, but identifying them could improve surgical outcomes. Our goal was to analyze the effect of patient characteristics and radiographic parameters on the development of symptomatic ASD requiring revision surgery after posterior lumbar fusion.Methods: In this retrospective cohort study, we identified patients who underwent lumbar fusion surgery and revision surgery from May 2012 to November 2018 using an institutional lumbar fusion registry. Patients having both pre- and post-operative upright radiographs were included in the study. Revision surgeries for which the index operation was performed at an outside hospital were excluded from analysis. Univariate analysis was conducted on candidate variables, and variables withP< 0.2 were selected for multivariate logistic regression.Results: Of the 106 patients identified, 21 required reoperation (29 months average follow-up). Age >65 years (OR 4.14, 95% CI 1.46–11.76,P= 0.008), body mass index (BMI) >34 (OR 1.13, 95% CI 1.04–1.23,P= 0.004), and osteoporosis (OR 14, 95% CI 1.38–142.42,P= 0.03) were independent predictors of reoperation in the multivariate analysis. Increased facet diastasis at fusion levels (OR 0.60, 95% CI 0.42–0.85,P= 0.004) was associated with reduced reoperation rates. Change in segmental LL at the index operation level, rostral and caudal facet diastasis, vacuum discs, and T2 hyperintensity in the facets were not predictors of reoperation.Conclusion: Age >65, BMI >34, and osteoporosis were independent predictors of adjacent-segment reoperation after lumbar spinal fusion.

BACKGROUND AND OBJECTIVES: Return-to-work (RTW) is an important outcome for employed patients considering surgery for cervical spondylotic myelopathy (CSM). We conducted a post hoc analysis of patients as-treated in the Cervical Spondylotic Myelopathy Surgical Trial, a prospective, randomized trial comparing surgical approaches for CSM to evaluate factors associated with RTW. METHODS: In the trial, patients were randomized (2:3) to either anterior surgery (anterior cervical decompression/fusion [ACDF]) or posterior surgery (laminoplasty [LP], or posterior cervical decompression/fusion [PCDF], at surgeon's discretion). Work status was recorded at 1, 3, 6, and 12 months postoperatively. For patients working full-time or part-time on enrollment, time to RTW was compared across as-treated surgical groups using discrete-time survival analysis. Multivariate logistic regression was used to assess predictors of RTW. Clinical outcomes were compared using a linear mixed-effects model. RESULTS: A total of 68 (42%) of 163 patients were working preoperatively and were analyzed. In total, 27 patients underwent ACDF, 29 underwent PCDF, and 12 underwent LP. 45 (66%) of 68 patients returned to work by 12 months. Median time to RTW differed by surgical approach (LP = 1 month, ACDF = 3 months, PCDF = 6 months; P = .02). Patients with longer length-of-stay were less likely to be working at 1 month (odds ratio 0.51; 95% CI, 0.29-0.91; P = .022) and 3 months (odds ratio 0.39; 95% CI, 0.16-0.96; P = .04). At 3 months, PCDF was associated with lower Short-Form 36 physical component summary scores than ACDF (estimated mean difference [EMD]: 6.42; 95% CI, 1.4-11.4; P = .007) and LP (EMD: 7.98; 95% CI, 2.7-13.3; P = .003), and higher Neck Disability Index scores than ACDF (EMD: 12.48; 95% CI, 2.3-22.7; P = .01) and LP (EMD: 15.22; 95% CI, 2.3-28.1; P = .014), indicating worse perceived physical functioning and greater disability, respectively. CONCLUSION: Most employed patients returned to work within 1 year. LP patients resumed employment earliest, while PCDF patients returned to work latest, with greater disability at follow-up, suggesting that choice of surgical intervention may influence occupational outcomes.

Background/Objectives: Spinal fusion surgery is an accepted form of management for select patients who suffer from degenerative lumbar disease. The need for cost-effective durable techniques is paramount as our population ages. This study compares the radiographic and clinical outcomes of PEEK and 3D-printed titanium interbody cages. Methods: This study compared two cohorts which underwent either PEEK or 3D-printed titanium (3DPT) interbody fusion at a single institution between 2013 and 2022. The PEEK cohort was a retrospective analysis of a prospectively collected registry. The 3DPT data were prospectively collected. The inclusion criteria were adults >18 years who underwent 1 or 2 level lumbar interbody fusion for degenerative spine disease with at least 6 months follow-up. Patient demographics, radiographs, and PROMs were collected. The cohorts were compared using ANOVA for continuous variables and Fisher’s exact test for categorical variables, with significance set to 0.05. Results: The final study included 91 patients, 49 PEEK and 42 3DPT. The 3DPT patients were older (p = 0.047) with increased incidence of hypertension (p < 0.001). The 3DPT patients had less bone morphogenetic protein (BMP) usage (80.9% vs. 54.8%; p = 0.012), but more cellular allograft (p < 0.001). Fusion rate was high for both cohorts, with PEEK at 95.9% and 3DPT at 97.6%. There was no significant difference in reoperation rate. Both the PEEK and 3DPT cohorts demonstrated an improvement in the Oswestry Disability Index (ODI) and EuroQol 5 Dimension (EQ-5D) at 1 and 2 years compared to preoperative baseline. More patients in the 3DPT group met the MCID for EQ-5D at 1 and 2 years compared to PEEK; however, this was not significant (p = 0.350; p = 1.000). Conclusions: The 3DPT interbody provided comparable if not superior fusion properties to the PEEK interbody given the decreased use of BMP. Both cohorts demonstrated similar improvements in ODI and EQ-5D compared to preoperative baseline. These results suggest that 3DPT cages may be a cost-effective alternative in spinal fusion. Further studies utilizing a larger population with higher follow-up rates are indicated to determine the economic and clinical benefits of 3DPT compared to PEEK cages in lumbar fusion surgery.

BACKGROUND AND OBJECTIVES: The appropriate utilization of lumbar fusion when performing laminectomy for lumbar spondylolisthesis is uncertain. The objective was to determine whether the use of a surgical expert review panel recommending fusion might improve patient selection, possibly reducing surgical failures. METHODS: Randomized clinical trial of patients with symptomatic degenerative lumbar stenosis with spondylolisthesis enrolled from 14 North American hospitals was conducted with patients randomized to receive an expert panel review of their case or not. Spinal expert review consisted of 10 to 15 surgeons' review of patient images and clinical data with voting on the appropriateness of fusion. Primary outcome was the percentage of patients who failed to improve their 1-year EuroQol-5 Dimension (EQ-5D) score. Secondary analysis focused on whether a supermajority (>80% consensus) of spinal experts recommending fusion might reduce operative failures. The trial (SLIP II) was registered at ClinicalTrials.gov (NCT03570801). RESULTS: Between November 1, 2017, and June 30, 2022, 663 patients were randomized (mean age 65.6 years; [59.6%] female) and 523 of 574 patients (91%; who had surgery) were included in the 1-year analysis. Final follow-up was on March 5, 2024. Among the 523 patients, 270 underwent review and 253 had no review. The overall surgical failure rate (using EQ-5D) did not differ between the review groups, 16.7% vs 17.4% (no review: difference 0.7%; 95% CI, −8% to 6%; P = .92). However, with supermajority recommending fusion, the proportion of patients who failed to improve EQ-5D score after surgery was 8.4% (review group) vs 18.4% (nonreview group: difference 10%; 95% CI, 2%-18%; P = .03). Supermajority recommendation for fusion was associated with 0.296 vs 0.240 EQ-5D change in the nonreview group (difference 0.056, 95% CI, 0.002-0.108; P = .04). CONCLUSION: Among patients with grade I degenerative lumbar spondylolisthesis, an expert panel review with a supermajority favoring fusion was associated with a greater improvement in health-related quality of life and fewer surgical failures.

BACKGROUND AND OBJECTIVES: Surgery for cervical spondylotic myelopathy improves quality of life but remains expensive. We conducted a cost-effectiveness analysis of patients treated with anterior cervical diskectomy/fusion (ACDF), posterior cervical decompression/fusion (PCDF), and laminoplasty (LP) in the Cervical Spondylotic Myelopathy Surgical (CSM-S) Trial, a randomized trial comparing surgical approaches for cervical spondylotic myelopathy. METHODS: In the trial, patients were randomized (2:3) to anterior (ACDF) or posterior surgery (LP or PCDF, at surgeon's discretion). A cost-effectiveness analysis was performed from a societal perspective with a 1-year time horizon, including only US patients as-treated. Cumulative costs were estimated using patient data on utilization and lost productivity using a human capital approach. Direct costs were calculated using 2022 Medicare rates for professional fees and cost-to-charge ratios for hospital services. Quality-adjusted life-years (QALYs) were calculated from patient responses to the EuroQol-5-Dimensions instrument at baseline and 3, 6, and 12 months postoperatively. Incremental cost-effectiveness ratio analysis was performed with bootstrapping to address uncertainty. RESULTS: Of 163 total patients enrolled in the CSM-S Trial, 153 from the United States (mean age, 62 years; 80 (52%) female) were included as-treated (ACDF = 61, PCDF = 64, LP = 28) in a cost-effectiveness analysis. Economic data were not available for 9 patients. The remaining 144 patients treated (ACDF = 55, PCDF = 61, LP = 28) had cost data through a 1-year follow-up. Mean hospitalization costs were higher after PCDF than ACDF and LP ($33 410 vs $26 468 vs $25 550; P < .001). Mean total costs were higher after PCDF than ACDF and LP ($62 383 vs $53 074 vs $47 426; P = .017). LP yielded greater QALY gains than ACDF (0.792 vs 0.732; P = .08) and PCDF (0.792 vs 0.698; P = .01). At a willingness-to-pay threshold of $150 000/QALY-gained, the probability that LP was cost-effective compared with PCDF was 99.7% and the probability compared with ACDF was 96%. CONCLUSION: In the CSM-S Trial, LP yielded greater 1-year quality-of-life improvements at lower costs than PCDF and ACDF.