The outcome of opening size based on the cervical curvature in laminoplasty

Abstract

Objective To discuss the feasibility and clinical effect between different cervical spine curvature and the laminoplasty opening size. Methods Seventy-six patients were involved in a retrospective study from February 2012 to January 2014, including of 48 patients of ossification of the posterior longitudinal ligament and 28 patients of multisegmental cervical spondylosis. All patients were divided into three groups according to their different curvature: cervical lordosis was less than 10° in group A, group B was more than 40°, group C was between 10° and 40°. According to different laminoplasty opening sizes (LOS), each group was divided into two subgroups, 12 mm (A1) and 10 mm (A2) for group A, 8 mm (B1) and 10 mm (B2) for group B, and 10 mm for group C. The JOA scores were estimated before surgery and one week after operation in each group. Postoperative C5 nerve root palsy occurrence rates were recorded. Results All the patients were followed up from 12.6 to 27 months, with a mean of (19.3±4.7) months. The mean JOA scores of one week after operation compared with preoperation had statistical difference (P 0.05) among the groups. The incidence of C5 nerve root palsy was 0 in group of A1 and A2, 1/9 in B1, 2/7 in B2 and 5.1%(2/39) in C. The incidence of group B2 was higher than other groups, but not statistically significant among groups (Hc=7.322, P>0.05). Conclusions The unilateral open door laminoplasty can achieve good result for multiple cervical spondylosis. It can obtain satisfactory functional recovery and reduce the incidence of C5 nerve root palsy based on different opening size according to different cervical curvature. Key words: Cervical spondylosis; Laminoplasty; Cervical curvature; Ossification of posterior longitudinal ligament