TREATMENT OF L5-S1 SPONDYLOPTOSIS BY STAGED L5 RESECTION WITH REDUCTION AND FUSION OF L4 ONTO S1 (GAINES PROCEDURE)

Study Design and Objectives. A retrospective study was performed on the two-stage Gaines procedure for the treatment of spondyloptosis, evaluating indications, techniques, results, and patient satisfaction. Summary of Background Data. Sixteen consecutive patients from two institutions were included. Their average age was 24 years. Average follow-up was 3.9 years, with 11 patients included in follow-up 2 or more years. Ten patients (63%) had a preoperative neurologic deficit-three with cauda equina syndrome, one with foot drop. All patients had severe back or radicular symptoms and significant disability or severe deformity. Methods. Patient examinations, interviews, chart review, and radiographic measurements all were performed independently. A subjective questionnaire was administered to each patient comparing preoperative with postoperative changes in pain, function, and appearance, as well as their overall outcome assessment. Results. Postoperatively, 12 patients (75%) had early neurologic deficits, with seven of these having had a preoperative deficit. Four of these seven had a persistent deficit at follow-up, one with a permanent foot drop and three with documented weakness that was still improving at follow-up. The patient with preoperative foot drop remained unchanged, and the remaining seven patients with early deficit all recovered within 1 year. All three patients with preoperative cauda equina syndrome recovered postoperatively. The subjective questionnaire results revealed extremely high patient satisfaction. They reported significant improvement in pain, function, and appearance. Conclusions. Despite the relatively high complication rate, with appropriate patient selection, planning, and surgical technique, this procedure appears to be a sound method for treating severe cases of spondyloptosis, yielding very high patient satisfaction.