Outcomes of minimally invasive spine decompression in lumbar spinal stenosis and intervertebral disc prolapse: A prospective study

Abstract

Introduction: Lumbar spinal stenosis and intervertebral disc prolapse are the most common cause of back pain and sciatica. Both conditions are traditionally treated by a midline lumbar incision, after which the paraspinous muscles are elevated from the spinous processes and lamina and retracted laterally and extensively. Minimally invasive lumbar decompression is a procedure designed to debulk hypertrophied ligamentum flavum and removal of the herniated disc with a goal of relieving neural compression. Our study aimed to assess the outcome in terms of improvement in neurology, extent of pain relief in the postoperative period and complications in patients undergoing minimally invasive spine decompression.Methodology: The present study was conducted in a tertiary care hospital. A total of 16 patients who satisfied both the inclusion and exclusion criteria and gave informed consent were recruited for the study from January 2020 to March 2021. All patients underwent minimally invasive spine decompression by tubular retractors. Outcome measures used are Visual analog score for leg pain and back pain, Modified Oswestry Disability Index (MODI), Roland Morris Disability Questionnaire (RMDQ) and neurological examination preoperatively and postoperatively at 6 weeks, 3 months and 6 months.Results: Out of 16 patients, ten patients had intervertebral disc prolapse and six had lumbar spinal stenosis. L4L5 was the most common level seen in our patients. Mean pre-operative VAS score was 6.88 and 4.44 for leg pain and back pain, there was significant reduction at the end of 6 months. Mean preoperative MODI score was 66.38, preoperatively 13 patients (81%) had crippling back pain, 3 patients (18.75%) had severe disability. At the end of 6 months, all 16 patients had less than minimal disability. Mean preoperative roland morris disability score was 11.31+ 0.61. There was a significant mean improvement at 6 months postoperatively from the preoperative baseline score. Nine patients (43.8%) had a motor deficit of which 4 patients had a significant motor power improvement. Two patient had complications, one patient had CSF leak intraoperatively and the other patient developed a superficial wound infection.Conclusion: Minimally invasive spine surgery is an excellent surgical option in patients with lumbar spinal stenosis and prolapsed intervertebral disc. Patients who underwent minimally invasive spine decompression had satisfactory functional outcome in terms of pain relief, minimal hospital stay and early return to day to day activities.