Lumbar stenosis surgery: the experience of the orthopaedic surgeon.

Between 1974 and 1989 350 patients were submitted to surgery for the treatment of stenosis of the lumbar canal; in 280 of these cases a minimum two-year follow-up was obtained. In all of the cases there was significant stenosis of the spinal canal, which was furthermore secondary to hypertrophy of the facet joints of degenerative nature. In 67% of the cases neurogenic claudication was present; in 57% there was monolateral radiculopathy, in 43% bilateral radiculopathy. The lesions extended from L4 to S1 in 39.2% of the cases, L3 to S1 in 36.3%, L5 to S1 in 8.5%, L2 to S1 in 7.2%, L4 to L5 in 4.6%, and L3 to L4 in 2.1%. Radiological diagnosis was confirmed by myelography and CT scan. Surgery involved laminectomy leaving intact at least 6 mm of the posterior facet joints in order to avoid destabilizing the spine; moreover, the anteromedial portion of the joint osteophytes was removed in order to release the lateral recess and, when necessary, decompression was extended to the intervertebral foramen. During the first years of our experience fusion of the posterior joints with osteosynthesis using plates and pedicular screws was associated with decompression in 43% of the cases. Thereafter, fusion was performed in only 17% of the cases. From a subjective point of view the results obtained in radiculopathies were satisfactory in only 87% of the cases, objectively in 72%. The results obtained with treatment of lumbar pain was better in patients in whom lumbosacral fusion was associated as compared to cases treated with laminectomy alone (85% vs. 65%). Complications were rare and mild.