A modified surgical technique of lateral lumbar interbody fusion

Objective To present the modified surgical technique of lateral lumbar interbody fusion and investigate its approach related complications. Methods Fifty-eight patients treated with novel surgical technique of lateral lumbar interbody fusion (LLIF) from June 2016 to January 2017 were studied retrospectively. There were 24 males and 34 females, aged from 45 to 82 years old (averaged at 66.1±12.1). The diagnosis was as following: degenerative spinal scoliosis in 24 cases, degenerative lumbar spinal stenosis in 16, lumbar spinal spondylolisthesis in 14, spinal infection and spinal trauma in 2 respectively. The modified surgical technique included operation under direct visualization, the safety transpsoas approach and the adjustable microretractor. The patient was placed in a lateral decubitus position, and a transverse or oblique skin incision was planned using fluoroscopy to target the center of the desired disc spaces. The 3 abdominal layers were split longitudinally along the muscle fiber. The psoas major was split longitudinally along the muscle fiber according to the safety working window. The adjustable microretractor was used as working corridor to carry out interbody fusion. Oswestry disability index (ODI) was used to assess the clinical outcome. The surgical time, estimated blood loss and approach related complications (pain/numbness at anterior thigh, weakness of psoas muscle and quadriceps) were recorded. Results All patients were followed up from 6-12months, the mean follow-up time (9.1±2.3) months. A total of 132 levels were performed with novel surgical technique of LLIF, one level in 19 cases, 2 levels in 10, 3 levels in 23 and 4 levels in 6 cases. The mean surgical time was (57.2±13.3) min for 1 level, (94.5±31.3) min for 2 levels, (129.8±42.1) min for 3 levels and (208.3±22.7) min for 4 levels. The estimated blood loss during surgery was less than 10ml every level. Preoperative ODI was 61.8%±20.1%, it was 22.5%±18.3%(t=7.572, P=0.000) at the last time follow-up. The incidence rate of approach related complications was 12.1%(7/58), with anterior thigh pain in 6 cases (10.3%), numbness 5 cases (8.6%) and psoas major weakness 3 cases (5.2%). No quadriceps weakness, vascular injury, sympathetic nerve injury, visceral injury and ureteral injury was found in these series. The incidence rate of complications increased significantly in patients underwent three or more levels interbody fusion (χ2=4.453, P=0.035). Conclusion The modified surgical technique reduces the approach related complications of traditional lateral lumbar interbody fusion through the operation under the direct visualization, the safety transpsoas approach and the adjustable microretractor. Key words: Lumbar Vertebrae; Spinal Fusion; Postoperative Complications