Outcomes Following Multilevel Cervical Disc Arthroplasty in the Young Active Population

Background: Cervical radiculopathy is a common disorder that portends significant morbidity. The presence of radiculopathy can have a debilitating effect on patients as well as a significant economic impact. Active duty military patients with increased physical occupational demands can be significantly impacted by cervical disease. The resulting disability can have a strong negative impact on operational readiness. Several studies have demonstrated comparably good functional outcomes between cervical disc arthroplasty (CDA) and anterior cervical discectomy and fusion for single-level disease. To date, no study has specifically evaluated the functional and occupational outcomes following adjacent 2-level CDA in a young, active patient population as represented by the active duty military population. Purpose: To evaluate functional and occupational outcomes following adjacent 2-level CDA for cervical radiculopathy in the U.S. military population. We hypothesized that this population would have excellent symptomatic relief at the cost of a low return to duty rate. Methods: We performed a case series with prospective follow-up of all patients who underwent adjacent two-level CDA at a single institution from 2011 to 2014. Each patient completed the Neck Disability Index questionnaire to assess functional outcome. Primary outcomes of interest were return to active military duty and complications. Results: Follow-up was available for 18 of 21 (85.7%) patients. At an average follow-up of 21.4 +/- 11.1 months, 12 patients (66.7%) reported complete symptomatic relief and were able to return to preoperative levels of function. Average self-reported pain score improved from 8.3 preoperatively to 1.1 postoperatively, and average postoperative Neck Disability Index score was 15.5 compared to 37.0 for those who medically retired. Radiographic analysis did not show any evidence of subsidence, migration of hardware, or heterotopic ossification. The average return to duty time was 9.6 weeks. Discussion: We demonstrate that adjacent two-level CDA is capable of providing predictable symptomatic relief and maintenance of a high-demand preoperative level of function for cervical radiculopathy among a population of young and highly active individuals. Adjacent two-level CDA offers significant relief of symptoms with low risk of complication in a young, active, and high-demand cohort such as the U.S. military. Adjacent two-level CDA can be performed with the expectation of improving function, relieving symptoms, returning to preoperative levels of activity, and maintaining operational readiness.