Treatment of cervical compressive myelopathy with a new dorsolateral decompressive procedure.

Object. A new dorsolateral decompressive procedure involving a unilateral approach has been devised for the treatment of cervical compressive myelopathy. In this operation, the posterior spinal elements of the contralateral side are not disturbed, and thus, postoperative deformity of the cervical spine can be avoided. Following decompressive surgery via the unilateral approach, the cervical spine was kept more stable compared with the results obtained after wide laminectomy or other expansive laminoplasty procedures. Methods. Twenty-six patients underwent dorsolateral decompressive surgery, and the patients' clinical and radiological results were examined during the follow-up period to evaluate neurological function and postoperative deformities of the cervical spine. The underlying conditions for myelopathy were cervical spondylosis (19 patients), ossification of posterior longitudinal ligament (three patients), and ossification of yellow ligament (four patients). The follow up period ranged from 6 to 110 months (average 35.5 months). Functional recovery, which was rated by using the Japanese Orthopaedic Association scoring system, was an average of 56% in all patients (100% being equal to full recovery). The recovery rate was compatible with those attained after other expansive laminoplasty procedures. Radiographically, progression to swan-neck or kyphotic deformity was not observed in any patient. No postoperative spinal instability was noted. Based on computerized tomography myelograph evaluation, the average transectional area of the dural tube at the C4-5 level was expanded from 122 mm(2) to 169 mm(2), and the transectional area of the spinal cord at the C4-5 level was expanded from 39.6 mm(2) to 52.9 mm(2) after surgery. Conclusions. The authors conclude that this operative procedure could be used as a new option for the treatment of cervical compressive myelopathy.