Objective: To report the outcome of anterior radical decompression for the treatment of severe ossification of the posterior longitudinal ligament (OPLL) with an average occupying ratio exceeding 50% in the cervical spine.
Methods: From July 2002 to February 2006, 26 patients with cervical OPLL occupying ratio of the spinal cord exceeding 50% underwent anterior decompression and fusion. There were 18 males and 8 females. The average age was 59 years (ranged from 43 to 73 years) and the mean occupying ratio was (65 +/- 20)%; Before operation, the JOA score was 8.7 +/- 2.8, and the sagittal diameter of spinal cord was (25 +/- 7)%. The ossified ligament was classified into two groups, the base-open group and the base-closed group. The occupying ratio was measured on 3-D CT scans, and the sagittal diameter of the deformed spinal cord was measured at the narrowest level on sagittal T2-weighted MRI. All patients received anterior decompression with the ossified ligament removed completely. Among them, 10 cases underwent one level corpectomy combined with one level diskectomy, 3 cases underwent 2 level corpectomy, and the other 13 patients underwent one level corpectomy. The decompressed segments were reconstructed either with a iliac crest strut or a titanium cage, and an anterior locking plate was implanted to prevent graft extrusion in every patient. All patients were monitored with ECP during decompression.
Results: The occupying ratio decreased to (10 +/- 5)%, the sagittal diameter of spinal cord increased to (75 +/- 15)%, and the average diameter of spinal cord at the narrowest site increased 3 times after operation. The JOA score was 14.2 +/- 2.5, with an average improvement ratio of (61 +/- 24)%. Three patients accompanied with diabetes presented with temporarily neurological deterioration. There were two cases complicated with cerebrospinal fluid leaks but cured within 2 weeks after surgery. One case accompanied with diabetes underwent a second emergency reexploration for hematoma in the spinal canal which caused a dyspnea.
Conclusions: Anterior radical decompression is an optimal method for the management of severe OPLL in the cervical spine. Higher rate of neuro-function recovery can be anticipated.