Results of surgery for spinal stenosis adjacent to previous lumbar fusion

The literature provides little data to guide surgical management of spinal stenosis adjacent to previous lumbar fusion. Thirty-three consecutive patients who had surgical decompression for spinal stenosis at the lumbar segments adjacent to a previous lumbar fusion were studied. The mean interval between fusion and the adjacent segment surgery was 94 months. Of the 33 patients, 26 were followed for 3-14 years (mean: 5 years) after adjacent segment surgery and were clinically evaluated and independently completed an outcome questionnaire. Of the 26 patients, 15 rated their outcome as completely satisfactory, 6 were neutral toward the surgery, and 5 considered their surgery a failure. The surgery was generally effective at improving or relieving lower extremity neurogenic claudication. The strongest independent predictive factor of patient dissatisfaction was ongoing postoperative low back pain (r = 0.7, p = 0.001). A higher back pain score at follow-up was associated with continued narcotic use (p = 0.001) and decreased ability to perform activities of daily living (p = 0.05). Six patients required further lumbar surgery during the follow-up period. This study provides the longest published follow-up data of surgical results for symptomatic spinal stenosis adjacent to a previously asymptomatic lumbar fusion.