Effects of endoscopic modified total laminoplasty on symptomatic lumbar spinal stenosis

Objective To summarize the operation procedure and experience of endoscopic modified total laminoplasty (EMTL), and to investigate its short-term therapeutic effects on symptomatic lumbar spinal stenosis. Methods The clinical data of 22 patients with lumbar spinal stenosis who underwent EMTL in the First Affiliated Hospital of Zhengzhou University from August 2016 to August 2017 were retrospectively analyzed. The age, hospital stay, prior and posterior diameters in sagittal plane, bleeding volume, operation time, incision length, intraoperative and postoperative complications of the two groups were recorded. The effects of operation were evaluated by the visual analogue scale (VAS) of lumbago and lower extremity pain, Oswestry disability index (ODI) and Japan Orthopedic Association (JOA) score before and 1 year after operation. Results Among the 22 patients, 8 males and 14 females were included in the study, mean age (59.3 ± 9.6) years. All patients had neurogenic intermittent claudication with a distance of (339± 130)m. Eight patients showed spondylolisthesis or instability according to preoperative digital radiography (DR), computed tomography (CT) and magnetic resonance imaging (MRI). The VAS, ODI and JOA scores of lumbago and lower extremity pain 1 year after operation were significantly different from those before operation (P<0.05). The mean differences (95% confidence interval) of lumbago VAS, lower extremity VAS, ODI score and JOA score were 5.0 (4.3, 5.6), 4.1 (3.3, 4.8), 38.6 (35.7, 1.5), -14.2 (-16.2, -12.2), respectively, which were significantly improved, compared with those before operation. There was 1 case of dural injury during the operation, and 1 case of replantation without fusion determined by postoperative reexamination. And there was no other complications. Conclusions EMTL is effective in the treatment of symptomatic lumbar spinal stenosis. It can alleviate the symptoms of patients, improve their quality of life and satisfaction, with good safety. Key words: Laminoplasty; Total laminectomy; Minimally invasive; Endoscopy