A comparative study of surgical outcomes between anterior cervical discectomy with fusion and selective laminoplasty for cervical spondylotic myelopathy

Few studies have directly compared anterior and posterior surgical approaches in cervical spondylotic myelopathy (CSM) patients with short-segment disease. We aimed to examine and compare surgical outcomes of anterior cervical discectomy with fusion (ACDF) and selective laminoplasty (S-LAMP) in CSM patients with 1- or 2-level disease.Forty-six patients, who received surgeries for CSM, were prospectively investigated; 24 underwent ACDF and 22 underwent S-LAMP. Average follow-up was 3.5 years. The following pre- and postoperative radiographic measurements were recorded: (1) C2-7 angle, (2) local angle (lordotic Cobb angle at operative level), (3) cervical sagittal vertical axis (SVA) (center of gravity of the head-C7 SVA), and (4) C7 slope. Outcomes were evaluated using the Japanese Orthopedic Association scoring system for cervical myelopathy (C-JOA score), neck pain visual analog scale, and neck disability index (NDI).There were no significant differences in patient demographics between the two groups. Postoperatively, C2-7 angle, local angle, cervical SVA, C7 slope, C-JOA score, and neck pain and NDI scores were not significantly different between the two groups; however, the recovery rate of the C-JOA score was superior in the ACDF group (57.5%) compared to the S-LAMP group (42.1%). The recovery rate of the C-JOA score in the local lordosis subgroup (local angle ≥ 0°) showed no significant difference between the two surgical groups. However, in the local kyphosis subgroup (local angle < 0°), C-JOA score recovery rate was worse after S-LAMP (20.4%) than ACDF (57.9%); local angle also worsened postoperatively after S-LAMP.In patients with local lordosis at the segments of cervical spondylosis and spinal cord compression, S-LAMP showed equivalent surgical outcomes (neurological recovery, neck pain and NDI scores, and cervical alignment) to ACDF. However, in patients with local kyphosis, S-LAMP worsened the kyphosis and resulted in worse neurological recovery.