Surgical results of anterior corpectomy in the aged patients with cervical myelopathy

Abstract

Retrospective study on the results of anterior corpectomy for the treatment of cervical myelopathy in patients over 70 years old. To evaluate the surgical results of anterior corpectomy in aged patients with multilevel cervical myelopathy and to investigate the probable pathomechanism by radiographic study. There are few data focused on the surgical results and post-operative complications of anterior corpectomy in aged patients with cervical myelopathy. Twenty patients 70 years of age or older who underwent anterior corpectomy, titanium mesh cage (TMC) reconstruction and anterior plate fixation for the treatment of compressive cervical myelopathy were reviewed. The average age at the time of operation was 75 years. Neurologic deficits before and after surgery were assessed using a scoring system proposed by the Japanese Orthopedic Association (JOA Score). Clinical results and post-operative complications were compared with those of patients 69 years old or younger as a control. Pre-operative Radiologic evaluation of every patient consisted of anterior-posterior, lateral, bilateral oblique, flextion, and extension radiographs, computed tomography and magnetic resonance imaging of the cervical spine. Any factor causing spinal cord compression and the sign of cervical instability were recorded. Surgical-related complications occurred in seven patients in the aged group. The incidence of complications was 35% in the aged patient group and 9.7% in the control group respectively. Although the difference was striking, no statistical significance was found between the two groups. One patient died of respiratory failure resulting from pulmonary infection. The mortality rate was 5%. The pre-operative mean JOA score was 9.3 (from 3 to 14) in the aged patient group. Nineteen patients were followed at least 2 years and the mean JOA score was 13.4 (from 8 to 17). 68.4% of the aged patients achieved a good or excellent result. There was no statistical difference in the recovery rate of JOA score between the aged group (58.1%) and control group (67.0%). In the pre-operative radiographs, the incidence of cervical instability was much higher in the control group (32%) than in the aged group (5%) and multilevel cord compression caused by posterior disc space osteophytes was more common in the aged group. Anterior corpectomy combined with TMC fusion and plate fixation provides favorable neurologic recovery even in the patients over 70 years old. However, the incidence of surgical related complications shows a conspicuous increasing in the aged patients. Overcompensation mechanism for cervical instability is the probable cause of degenerative cervical spondylotic myelopathy in aged patients.