Feasibility of Posterior Cervical Foraminotomy for Adjacent Segmental Disease after Anterior Cervical Fusion

OBJECTIVE: The aim of this study is to evaluate the feasibility of posterior cervical foraminotomy (PCF) for adjacent segmental disease (ASD) after anterior cervical fusion (ACF). As ACF is accepted as the standard treatment for cervical spondylosis, many studies have been conducted to evaluate the efficacy of various surgical techniques to overcome symptomatic ASD after the previous surgery. Herein, PCF was performed for the treatment of symptomatic ASD and the feasibility of the surgery was evaluated. METHODS: Forty nine patients who underwent PCF due to symptomatic ASD from August 2008 to November 2017 were identified. For demographic and perioperative data, the sex, age, types of previous surgery, ASD levels, operation times, and bleeding amount were recorded. The clinical outcome was assessed using the visual analogue scale for the neck and arm, the modified Odom’s criteria as well as neck disability index. Radiologic evaluations were performed by measuring disc softness, disc height, the cervical 2–7 sagittal vertical axis, cervical cobb angle, and facet violation. RESULTS: Thirty-seven patients were enrolled in this study. The patients were divided into two groups based on the location of the pathology; paracentral (group P) or foramina (group F). Both groups showed significant clinical improvement (p<0.05). The proportion of calcified disc and facet violations was significantly larger in group F (p<0.05). The minimal disc height decrease with mild improvement on sagittal alignment and cervical lordosis was radiologically measured without statistical significance in both groups (p>0.05). CONCLUSION: PCF showed satisfactory clinical and radiologic outcomes for both paracentral and foraminal pathologies of ASD after ACF. Complications related to anterior revision were also avoided. PCF can be considered a feasible and safe surgical option for ASD after ACF.