Free-run electromyography assisted interlaminar endoscopic lumbar disckectomy at L4L5 and L5S1 under general anesthesia

Abstract

Introduction: Interlaminar Endoscopic Lumbar Disckectomy has been found to offer symptomatic alleviation comparable to open disckectomy while reducing blood loss, postoperative discomfort, complications, hospital stay, and narcotic use. General anesthesia decreases intraoperative stress, but surgeons may not be sure whether they injure nerve roots. Free-run electromyography may protect nerve roots that are thought to be in danger from surgery. Methods: Patients with L4L5 or L5S1 lumbar disc herniation were treated with IELD. EMG was monitored via needle electrodes in lateral vastus lateralis, anterior tibialis, abductor hallucis muscles. Surgeons were asked to halt the surgery and adjust their manipulation right when abnormal EMG appeared on the screen. The severity of signs and symptoms were noted pre- and post-operatively. Results: In all 26 cases, the median of visual analogue scale (VAS) of low back pain was 4.5. That of radicular pain was 7. Two patients had motor weakness at L4 or S1 muscles. One patient has sensory loss at L5 dermatome. The level of disc herniation was 46% at L4L5 and 56% at L5S1. The complications included only superficial infection in two patients that were effectively managed with antibiotics. During postoperative follow-up, all patients recovered completely without any neurological deficit. f-EMG signal included uneventful (9 patients), burst/ spike (10 patients), A-train (3 patients, and C-train (4 patients) Conclusion: Free-run EMG is a protective mean in IELD. All surgeons will profit from this technique in the early stages of their learning curve. To examine the outcomes, further comparative research and prospective, ran- domized, controlled trials should be undertaken.