AUTOMATED PERCUTANEOUS LUMBAR DISKECTOMY - A PROSPECTIVE MULTIINSTITUTIONAL STUDY

PURPOSE: A prospective study in 10 independent hospitals from 1992 to 1994 evaluated automated percutaneous lumbar discectomy (APLD) with a newly designed percutaneous instrument. MATERIALS AND METHODS: One tho usand five hundred eighty-two APLD procedures were performed in 1,525 patients with disc herniation or back pain. Mean follow-up after APLD was 18.3 months. Follow-up of at least 1 year was available in 1,474 p atients. One thousand two hundred eighty-nine patients had sciatic pai n and 185 had back pain only. Eight hundred twenty-two patients had sy mptoms for less than 2 years, 652 for more than 2 years. One thousand two hundred sixty-two patients were older than 60 years, 212 were youn ger than 60 years. Nine hundred fifty patients had disc protrusion, an d 357 had sequestration. Forty-eight patients had disc or longitudinal ligament calcification. Twenty-two had previous surgical discectomy. All discectomies were done with use of a straight needle with the pati ent in the lateral decubitus position. RESULTS: Success rate (measured by Hijikata's criteria) was 83% at 1 year. Success was significantly greater for protrusion versus sequestration (86% vs 72%, P < .001); fo r back pain alone versus leg and back pain (89% vs 80%, P < .005); for duration of symptoms less than 2 years versus more than 2 years (85% vs 79%, P < .005); and for age younger than 60 years versus older than 60 years (84% vs 76%, P < .01). Among postsurgical patients, success rate was 77% (17 of 22 patients). The only complication was discitis ( 0.06%, nine patients). Technical success at L5-S1 was 99% (795 of 800) . CONCLUSION: APLD with Teng's instrument has excellent results, Indic ations may include back pain alone. A straight needle can be used at L 5-S1 in most patients, with proper positioning.