Dynesys System Implantation through Wiltse Approaches for the Treatment of Degenerative Lumbar Spinal Stenosis

Abstract：Objective To observe the early clinical outcomes and safety of hemilaminectomy and Dynesys system implantation through Wiltse paraspinal approach and conventional posterior midline approach for the treatment of single-segment degenera-tive lumbar spinal stenosis. Methods 32 patients with single-segment degenerative lumbar spinal stenosis were treated by hemilaminectomy and Dynesys system implantation and divided into 2 groups according to the different surgical approaches. The effects were evaluated by operation time,bleeding volume,postoperative drainage volume,incision pain and post operation dysfunction. Incision pain was measured by visual analog scale(VAS)on the 3rd day and the 14th day after operation. Post operation dysfunction was measured by Oswestry disability index(ODI)on the day before operation,in the 1st month and the 6th month after operation. Results 32 patients were followed up for 6 to 9 months. The statistics showed that there were less operation time,bleeding volume,and postoperative drainage volume in the Wiltse paraspinal approach group(P ﹤ 0. 05). The VAS scores of the 3rd day and the 14th day after operation were lower in wiltse approach group than in conventional posterior midline approach(P ﹤ 0. 05). The ODI scores in the 1st month were lower in wiltse approach group(P ﹤ 0. 05),but there were no differences in ODI scores 6 months after operation. Conclusion The results suggested that Wiltse approach has less nega-tive effect on paraspinal muscles than conventional approach and has advantages of less injury,less bleeding and quick recover-y. So it complys with the concept of minimally invasive surgery and is worth to be popularized in clinic practices.