Long-term outcome after microendoscopic diskectomy for lumbar disk herniation: a prospective clinical study with a 5-year follow-up.

BACKGROUND: Several authors have reported results obtained with the microendoscopic diskectomy (MED) technique, but the long-term outcome has not been described. This report summarizes our clinical experience with the lumbar MED technique with a long-term follow-up period. OBJECTIVE: To evaluate the efficacy of the MED for lumbar disk herniation and to report long-term outcome and complications (5-year follow-up). METHODS: One hundred twenty consecutive patients with lumbar disk herniation were treated with the METRx system.We included all types of lumbar herniated disks: contained, not contained, foraminal, and migrated disk herniations. The results were evaluated with the Visual Analog Scale (VAS) pain score, Oswestry Disability Index score, patient satisfaction questionnaire, and modified Macnab criteria. RESULTS: The average age of patients was 41 years; 65 were men and 55 were women. The most commonly affected level was L5-S1 (54.2%). The follow-up time after surgery was 5 years in all cases. We obtained good or excellent results in 75% of patients and regular results in 18%. Good subjective satisfaction was observed with surgery in 92% of patients. The mean decrease in the Oswestry Disability Index score was 52.8 ± 21.6; the mean decrease in leg VAS score was 6.1 ± 2.3; and the mean decrease in lumbar VAS score was 1.9 ± 3.3. Adjusted mean differences were statistically significant in all cases (P < .05). CONCLUSION: MED not only reduces the incision, tissue damage, and postoperative period of incapacity but also offers long-term results comparable to those of conventional techniques.

Midterm outcome after microendoscopic decompressive laminotomy for lumbar spinal stenosis: 4-year prospective study.

OBJECTIVE: To evaluate the efficacy of radicular decompression in lumbar spinal stenosis using a microendoscopic technique. METHODS: This was a longitudinal prospective study of 50 patients with a diagnosis of lumbar spinal stenosis who were treated by microendoscopic decompression using an 18-mm METRx tubular retractor according to the METRx technique (Medtronic Sofamor Danek, Memphis, TN). Twenty of the patients had an additional disc prolapse, and a microendoscopic discectomy was associated with decompressive laminectomy. The results were evaluated using the visual analog scale pain score, Oswestry Disability Index score, patient satisfaction questionnaire, and modified Macnab classification. RESULTS: The average age of the patients was 56 years; 29 (58%) were men and 21 (42%) were women. The most commonly affected level was L4-L5 (64%). The mean surgical intervention time was 94.3 (+/- 14.3) minutes. Mean postoperative hospital stay was 3.16 (+/- 2.3) days. The follow-up time after surgery was 4 years (48 +/- 6.6 months; range, 24-72 months). We obtained good or excellent results in 72% of patients, achieving good subjective satisfaction in 68% of the patients. The mean decrease in the Oswestry Disability Index score was 30.23 (+/- 24.29), the mean decrease in the leg pain visual analog scale score was 6.02 (+/- 2.57), and the mean decrease in the lumbar pain visual analog scale score was 0.84 (+/- 2.06). Adjusted mean differences were in all cases statistically significant (P < 0.05). CONCLUSION: Data indicate that, in our experience, on midterm follow-up, microendoscopic laminectomy decompression is an effective technique for the treatment of lumbar spinal stenosis.