Complications and reoperations in young versus old patients undergoing cervical disc arthroplasty

Background: Despite the growing popularity of cervical disc arthroplasty (CDA), there remains a lack of literature investigating outcomes in older patients and no consensus exists on an age threshold beyond which CDA is not recommended. This study aimed to compare outcomes between patients younger than 65 and those aged 65 and older undergoing CDA. Methods: Patients who underwent CDA at a major spine center (January 2009–December 2023), with at least 1 year of follow-up, were included. Two age-based cohorts were analyzed: younger (<65) and older (≥65). Both single and multilevel disc replacements were considered. Primary outcomes included comparing 90-day complications and all-cause reoperation rates in the 2 cohorts. Secondary outcomes included comparisons of patient characteristics, operative data, and length of stay (LOS). Frequencies, chi-squared analysis, and Student's t-test were used to compare cohorts. Results: A total of 298 CDAs were evaluated among 188 patients. There were 132 patients in the younger cohort (mean age: 48.9±10.2) and 56 in the older cohort (mean age: 69.5±3.8). Cohorts were similar with regards to body mass index, sex, and length of follow up. The overall 90-day complication rate was 23.8%. There was no difference in complication rates (younger: 23.3%, older: 25.0%, p=.60). Older cohort averaged more levels operated (older 1.8±0.6, younger 1.5±0.7, p=.006). The overall reoperation rate was 12.2% (young: 13.5%, older: 8.9%, p=.38). Subsidence was the most common cause of reoperation in both the younger (n=4, 3.0%) and older (n=2, 3.6%) cohorts. Conclusion: In this series, we found no statistically significant differences in 90-day complication or reoperation rates between younger (<65 years) and older (≥65 years) patients undergoing CDA. Subsidence emerged as the most common complication, occurring at similar rates in both cohorts. While further large-scale, long-term analysis is warranted to determine clinical outcomes of CDA in older patients, this study provides comparable complication and reoperation rates as in the younger population.