[Anterior radical decompression for severe ossification of the posterior longitudinal ligament in the cervical spine].

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.