Results of expansive laminoplasty for lumbar spinal stenosis in active manual workers.

Expansive laminoplasty was done on 18 selected patients with lumbar spinal canal stenosis who were active manual workers and 2 patients with cauda equina tumors from 1982 to 1990. Postoperative follow-up on the initial 10 cases of spinal stenosis was 1-7 years (mean, 3 years). Using computed tomography, the spinal canal was found to be enlarged with a nearly rectangular shape, and the mean percent enlargement was 119% (1.9 cm2). Spinal stability also was reinforced. The preoperative mean evaluation score (Japanese Orthopaedic Association score) was 10.4 (full scale, 29). The mean score improved to 24 postoperatively (mean percent improvement, 73%). These findings did not change during the long follow-up, and the satisfactory results were maintained.