[Lumbar canal stenosis. Retrospective study of 158 operated cases]

The authors report the results of a retrospective study of 158 lumbar spinal stenosis (LSS), all operated (111 degenerative, 26 congenital, 21 mixed). Eighty seven percent of the patients had a low-back pain and 81.6% a radicular pain. Only 57.6% of them had a polyradicular claudication. A neurological deficit (motor, sensitive, or involving sphincters) was present in 36.6% of cases. A myelographic block was noted in 23.4% of cases, and in 20.3% a spondylolisthesis with an intact neural arch was found. Surgery consisted of a posterior lateral spinal canal calibration, sometimes associated with a ventral canal calibration (via the posterior route) (6.3%), and/or excision of a disc herniation at one (47.5%) or two levels (3.8%). Mean follow-up after surgery was 7.8 months. The global result was good or excellent in 75.2% of cases. Radicular pain was relieved in 89.1% of cases, and polyradicular claudication in 90.1% of cases. Neurological deficit improved in 50.6% of cases. In only 59.8% of cases relief of low-back pain was achieved. Statistically low-back pain (lasting for over 2 years) improved less, but a preoperative spondylolisthesis didn't influence the quality of the result regarding this symptom. Semiology, pathophysiology, and surgery particularly regarding spine stability are discussed.