Benefit of degenerative posterior longitudinal ligament removal during anterior decompression in cervical spondylotic myelopathy.

It remains controversial whether degenerative posterior longitudinal ligaments should be removed during anterior decompression procedures for cervical spondylotic myelopathy. Few data are available from studies that have compared removing and retaining the degenerative posterior longitudinal ligament. The goal of this retrospective study was to evaluate the benefit of degenerative posterior longitudinal ligament removal during such operations. Clinical data on 130 patients with confirmed degenerative posterior longitudinal ligament who underwent anterior cervical decompression surgery were retrospectively reviewed. All procedures were performed by the same senior orthopedic surgeon at the authors' spinal surgery center. The degenerative posterior longitudinal ligament was removed in 62 patients (group A) and retained in 68 patients (group B). The 130 patients were followed for 36 months. The Japanese Orthopedic Association score improved from 9.0±2.7 to 14.7±1.5 in group A and from 9.4±2.6 to 14.1±1.7 in group B (P=.028). The recovery rate for spinal cord neurologic function was 66.7% in group A and 61.3% in group B (P=.031). Operating time was longer (P=.002) and the sagittal median diameter of the vertebral canal was enhanced in group A (P<.001). Narrowing of previously enlarged canals occurred at a significantly higher rate in group B (P=.044). No significant difference was found in the rates of common complications between groups. Removal of the degenerative posterior longitudinal ligament in anterior decompression procedures for cervical spondylotic myelopathy appeared to be beneficial and provided more complete decompression and better postoperative outcomes than surgery without removal of the ligament. Although this procedure was generally safe, it required longer operating times, was more technically challenging, and required more experienced surgeons than surgery without removal of the ligament.