[Clinical and radiological study on subtotal vertebrectomy for cervical myelopathy due to multiple-level involvement (author's transl)].

A technique for anterior decompression and fusion has been developed for cervical myelopathy involving two or three levels. The technique consists of subtotal resection of vertebral body or bodies between the involved levels; complete removal of posterior bony spurs, posterior longitudinal ligament, and bulged disc or disci; and interbody fusion with an iliac bone graft. A series of forty-seven patients who had been observed for periods of one to six years and ten months was analyzed in detail. Clinical results evaluated according to Crandall's criteria were "Excellent" in 23 cases (48.9%), "Improved"in 21 cases (44.7%), and "Unchanged" in 3 cases (6.4%). There was not even a single case showing aggravation of symptoms. Out of 33 cases with posterior bony spurs before surgery, 27 cases (81%) showed complete removal of the spurs on postoperative X-rays. The restoration of subarachnoid space was confirmed in nine cases by the postoperative myelogram performed four weeks after surgery. Some authors reported that the spinal fusion might accelerate the degenerative changes in adjacent levels. In this present study some radiological evidences of the degeneration in the adjacent vertebral segments and/or a change of the alignment in the cervical spine were observed. However, such changes were not so serious that a recurrence of myelopathy would occur. The maintenance of the physiological alignment of the cervical spine seems to be important to minimize the degenerative changes. This was also reconfirmed in six cases by the postoperative myelograms which were performed at least three years after surgery. Thus, even for cases with multiple-level involvement, this procedure has provided excellent results because of complete decompression and sufficient restoration of the subarachnoid space.