抄録
Our tentative criterion for application of micro-endoscopic surgery for lumbar degenerative spondylolisthesis with neurological symptoms has been <20% slippage. We investigated the 1-year postoperative results of 25 patients treated in this way (21 men and 4 women; mean age 68.4 years). Preoperative X-ray examination demonstrated that 8 patients showed no change of slippage during forward and backward bending, and these patients were classified as a stable group. The mean slippage in this group was 12.5%, and it had not changed at the 1-year follow-up point. The remaining 17 patients showing slippage change were classified as an unstable group in whom slippage in the middle position was 8.4±1.3° preoperatively and 9.2±1.3° at the 1-year follow-up point. The mean improvement ratio for the JOA score was 59.9% in the stable group and 47.0% in the unstable group. No patients needed additional surgery due to an increase of slippage or deterioration of symptoms. Micro-endoscopic surgery is able to cope with lumbar degenerative spondylolisthesis with slippage of <20%.
