Direct Decompression Via Lumbar Oblique Lateral Approach With Microscope

Objective To describe the surgical methodology and investigate the effectiveness of microscopic direct decompression via oblique lateral approach in patients with radiculopathy,as well as various concomitant degenerative lumbar diseases.Methods 11 patients suffering from radiculopathy with degenerative lumbar disease were treated with microscopic oblique lateral interbody fusion at our department between January 2016 and March 2017.Their clinical data was gathered and analyzed retrospectively,including 3 men and 8 women with a mean age of 55.3 years old and a mean BMI of 23.06 kg/m2.6 patients suffered from radicular pain on the left side,while 5 on the right side,with concomitant of lumbar instability in 4 cases,stenosis in 4 cases,degenerative spondylolisthesis in 1 cases,adjacent segment disease in 1 case and revision in 1 case(In this case,cage emigrated backward to compress the nerve on the left side postoperatively).The problematic intervertebral space was confined to single level,with 8 cases in L4/5 and 3 cases in L3/4.During the operation,herniated nucleus pulposus or other protrusions was removed anteriolaterally under microscopic vision.The removal was regarded complete if the posterior longitudinal ligament was identified and floated well.The clinical efficacy was evaluated by comparison of visual analogue scale(VAS),Oswestry disability index(ODI)preoperatively and postoperatively.The cross section area of the spinal canal(CSA),disc height(DH),segmental disc angle(SDA),foraminal height(FH)and lumbar lordosis(LL)were calculated preoperatively and postoperatively.Operative time,blood loss,incision length,length of stay and perioperative complications were observed.Results All operations went smoothly,with an average operation time of(149.9±24.8)min,blood loss(64.7±43.3)ml.All incisions were stage I healed,with a average length of 4.1cm.The average length of stay was(7.5±1.6)d,and the followup was 4.2 months on average,ranging from 2 to 13 months.There were statistically significant improvements in terms of VAS and ODI(P<0.01,P<0.01),as well as the cross section of the spinal canal,disc height,foraminal height and segmental disc angle(P<0.01,P<0.01,P<0.01,P<0.01).No statistical significance was found between preoperative and postoperative lumbar lordosis(P=0.359).During the follow-up,1 case of cage subsidence was observed.No other postoperative or perioperative complications,such as ventral dural sac injury?vascular injury?ureteral injury?lumbar plexus injury and were observed.Conclusion Direct ventral decompression through oblique lateral approach under microscope could achieve very satisfactory clinical results with minimal complications,which could expand the indication of OLIF in patients with radiculopathy.