Recovery process following cervical laminoplasty in patients with cervical compression myelopathy: prospective cohort study.

STUDY DESIGN.: Prospective cohort study. OBJECTIVE.: To investigate the recovery process after laminoplasty in patients with cervical myelopathy, and the effects of patient age and duration of symptoms before surgery on the recovery process. SUMMARY OF BACKGROUND DATA.: The surgical results of laminoplasty for cervical myelopathy have been well documented, but there have been few reports on the recovery process after cervical laminoplasty. METHODS.: The study group consisted of 98 patients who underwent double-door laminoplasty for cervical myelopathy. All cases were followed for a minimum of 5 years. The JOA score, 10 seconds grip and release test (10-second test), and grasp strength were evaluated at "fixed points" after surgery, and the recovery process in each subject was assessed. The maximum recovery time point, defined as the time point when the value just reached a plateau after surgery, was evaluated in each subject.Patients were divided into 2 groups by age (<70 years and > or = 70 years) or duration of symptoms before surgery (<1 year and > or = 1 year), and the effects of these factors on surgical results were investigated. RESULTS.: The preoperative values of all parameters significantly improved 5 years after surgery. The JOA score reached a plateau earlier (8.7 months) than did the grasp strength (21.7 months) and 10-second test (25.6 months). The maximum recovery time point of the JOA score was statistically late in the elder group (> or =70 years) compared to the younger group (<70 years). The recovery rates of the JOA score and the degree of recovery for the 10-second test in patients with symptoms lasting <1 year were statistically greater than those in patients with symptoms lasting > or =1 year. CONCLUSION.: The functional status assessed by the JOA score recovered within 1 year after surgery but further recovery can be expected up to 2 years after surgery. The comparative study suggested that patient age influenced the process of recovery, and the duration of symptoms before surgery influenced the degree of recovery.