Long-term Follow-up of Revision Decompressive Lumbar Spinal Surgery in Elderly Patients

Study Design: A retrospective study of elderly patients (more than 65 y of age) who underwent surgery for lumbar spinal stenosis between 1990 and 2000 was carried out. Among all these patients, the patients who underwent revision surgery were studied. Objective: To quantify the risk of reoperation in patients who underwent decompressive lumbar surgery and to analyze the connection between different variables before the primary surgery to the risk of surgical revision. Summary of Background Data: Lumbar decompressive spinal surgery is a very common procedure. However, the tendency of restenosis with clinical effect on the patients increases with time. Outcome studies reported that rate of reoperation has ranged from 0% to 23%. No studies so far analyzed the rate of reoperation in elderly patients in long-term follow-up and the different variables that contributed to it. Methods: Between 1990 and 2000, 357 patients more than 65 years of age underwent decompressive surgery for lumbar spinal stenosis with a mean follow-up of 64 months. Thirty-one patients (8.7%) were reoperated at least once. Twenty-five of them (81%) were followed. Demographic data, body mass index, associated comorbidities, preoperative risk as assessed by the scale of the American Society of Anesthesiology, type of surgery, pain perception by Visual Analog Scale, duration of symptoms, clinical presentation, walking ability (distance in meters), the level of basic activities of daily living was evaluated by the Barthel index, and overall satisfaction from the surgery were recorded and analyzed. For comparison between the reoperated patients and patients who were not reoperated, another group of 25 patients who were not reoperated (of our cohort) was studied. These patients were matched to the reoperated patients in terms of age (+/- 2 y), sex, body mass index, and time elapsed since surgery (+/- 3 mo). Results: Overall rate of revision surgery was 8.7% in a period of 70 months follow-up. Twenty-one patients (80%) underwent 1 revision surgery, 4 patients (16%) underwent 2 revisions, and 1 patient (4%) had 3 revisions. The mean pain-free interval was 26 months. There were no sex differences in the rate of reoperation (10% in females and 7% in males, P > 0.05). Although that only 36% of the patients were very or somewhat satisfied with overall revision results, significant improvement in pain perception (change in Visual Analog Scale score of 4.84, P < 0.001) and in functional status (Barthel index increased in 15.2 points, P < 0.001) were found after revision surgery. Six cases (19%) were operated in the first 2 years, 16 cases (52%) in the first 4 years, 24 cases (77%) in the first 6 years, and additional 7 cases (23%) were reoperated more than 6 years after the first operation. Conclusions: Even in reoperated elderly patients with spinal stenosis without spinal fusion, an improvement in functional status and somewhat in pain perception can be anticipated.