Transforaminal Lumbar Interbody Fusion For L5-S1(?°-? °) Spondylolisthesis Under Microscope

Objective To report the surgical method and the recent curative effect in the treatment of transforaminal interbody fusion(MIS—TLIF) for L5-S1 spondylolisthesis( ?°-? °) which assisted by the microscope. Methods To analyze 23 patients who were diagnosed L5-S1 spondylolisthesis(?°-? °) between August 2013 and May 2014.They were both be treated by MIS—TLIF which assisted by the neurophysiology monitoring, microscope and the expandable access system: one side line through the gap between the multifidus and the longissimus(Wiltse approach) to decompress nerve root and fuse centrum by cage, the other side line uses percutaneous pedicle screw internal fixation system assisted by C-arm X-ray machine. Analyzing the incision length, blood loss, operative time, postoperative incision pain duration, postoperative intervertebral fusion rate of this group of patients; JOA(Japanese orthopedic society) score and VAS(visual analog pain scale) score were analyzed preoperatively,1 week, 3 months, 6 months and 12 months postoperatively; X-ray examination of lumbar spine were achieved preoperatively, 1 week, 3 months, 6 months and 12 months postoperatively to assess the conditions of the intervertebral bone graft fusion, measurement of intervertebral height and internal fixation with pedicle screws. Results All patients accepted successful operation without nerve injury and endorhachis fracture, postoperative symptoms were significantly improved; The average of incision length was(3.12 ± 0.50) cm, the average of operation time was(182.8 ±12.5) min, the average of the amount of blood loss was(189.4± 17.3) ml, the average of the postoperative incision pain duration was(25.8 ± 3.4) h. There were no ischemic necrosis of skin incision, no incision infection and poor incision healing; VAS and JOA score obviously improved postoperative, 1 weeks, 3 months, 6 months and 12 months compared with that before operation, the difference was statistically significant(P < 0.05).This group of patients in the postoperative and follow-up period were both examined the lumbar X-ray which confirmed that postoperative achieved a good vertebral fusion, the fusion rate was 100%. The height of postoperative intervertebral space was recovered relatively compared with pre-operation, the difference was statistically significant(P < 0.05). The height of preoperative intervertebral space was(5.26±0.78)mm, a week after operation was(10.10 ±1.06)mm, 3 months was(10.06 ±1.00)mm, 6 months was(10.04 ±1.00)mm, 12 months was(10.02 ±0.97)mm. There were no obvious broken pedicle screws. Conclusions In the treatment of transforaminal interbody fusion(MIS—TLIF) for L5-S1 spondylolisthesis( ?°-? °) which assisted by the microscope, the intranperative blood loss and the length of the surgical incision can be reduced farthest, the intervertebral implanted cage can effectively restore the height of the intervertebral space. All these ensure the good fusion rate.