Neurologic signs in lumbar disc herniation. Preoperative affliction and postoperative recovery in 150 cases

We studied prospectively 165 consecutive patients operated on for lumbar disc herniations. Neurologic examination was performed preoperatively and at 4, 12, and 24 months postoperatively according to a protocol. Preoperatively 69% of the patients showed a neurological disturbance corresponding to the level of disc herniation and 62% a corresponding sensory deficit. Recovery of the neurological deficit was seen in half of the cases at 2 years postoperatively, the main part of this improvement occurred within 4 months after the operation. Neurologic recovery correlated to a good surgical outcome, and a short history of disc herniation prior to the operation correlated to postoperative neurologic improvement. The straight leg raising test correlated to preoperative neurologic deficit, but not to postoperative recovery. Motor power disturbance of the extensor hallucis longus muscle recovered in more patients than reflex disturbances. Sensory disturbances had the lowest recovery rate. Our study demonstrates a correlation between routine postoperative neurologic findings and the patient's self-assessed outcome of surgery.