多椎間頚椎 OPLL に対するβ-tricalcium phosphate を応用した前側方部分椎体削開術の短期成績

抄録

Object. We studied the changes in neurological status and radiological features of 16 patients undergoing the anterolateral partial vertebrectomies (ALPVs) with the use of beta-tricalcium phosphate (beta-TCP) for multilevel ossification of the posterior longitudinal ligament (OPLL) in the cervical spine during a 1-year follow-up. Methods. There were 11 male and 5 female patients. The patients' ages ranged from 37 to 81 years (mean 63 years). In ALPV the uppermost site was C2-C3 in 6 patients and the lowermost was T1-T2 in 1 patient. The site of ALPV consecutively ranged from 3 to 7 levels (mean 4.3). Beta-TCP was implanted into the site of the vertebrectomy with the exception of the two vertebral bodies (upper and lowermost) for each patient. The Neurosurgical Cervical Spine Scale (NCSS) was used to assess the patient's neurological status. The cervical lateral X-ray was used to measure the cervical curvature and the range of motion (ROM). A computed tomography scan was used to evaluate the degree of ossification of beta-TCP. Results. No patient showed any deterioration in neurological status during a 1-year follow-up. Twelve out of 16 patients showed an acceptable improvement (NCSS rate of improvement &ge;50%) and 6 patients showed a satisfactory improvement (NCSS rate of improvement 100%) at a 1-year follow-up. There was no significant change in the cervical curvature but ROM decreased by 23% as an average at a 1-year follow-up (p<0.0001, paired t-test). All beta-TCPs for each patient promoted new bone formation at a 6-month follow-up and were replaced by the compact bone with remodelling of the vertebral column at a 1-year follow-up. Horner's syndrome occurred in 2 patients but improved within a few months postoperatively. Conclusions. ALPV with the use of beta-TCP may be acceptable as a radical treatment for multilevel OPLL in the cervical spine.