Abstract

Purpose:  Very few prospective studies are available on the surgical outcome in patients with lumbar canal stenosis having a motor deficit. The study was aimed at evaluating factors affecting recovery of neurological deficits in cases of lumbar disc herniation (LDH) treated by lumbar decompression.
Methods A prospective study was performed at J.K. Hospital and Research Centre, Bhopal, M.P. India, from November 2019 to November 2021, on 35 patients. These patients present to us with complaints of weakness in ankle dorsiflexors (ADF) and extensor hallucis longus (EHL). In our study, all those patients were included who gave positive consent, who have L4 and /or L5 nerve root involvement innervating the anterior compartment of the leg and those who have lower extremity (ADF and EHL) weakness resulting from lumbar degenerative diseases like lumbar canal stenosis due to ligamentum flavum hypertrophy, facet arthropathy, disc protrusion and spondylolisthesis at L4-L5 level or L5-S1 level. Postoperative evaluations of motor recovery were performed regularly on an outpatient basis, and the results of the latest follow-up were analyzed. The follow up was done at 2 weeks, 12 weeks and 24 weeks in our OPD.
Result: 22(67.8%) patients having duration of symptoms less than 3 months had 95% recovery, group with duration of symptoms more than 3 month showed recovery rate of 70%. Recovery rate of 90% in ODI score in group with duration of symptoms less than 3 months. Following Kaplan and Meier analysis median time to foot drop improvement was within 12 weeks of surgical decompression. After the Kaplan and Meier plot, we observe that maximum recovery is seen between 9 and 14 weeks after decompression.
Conclusion:   Better improvement is seen if the patient got operated on within 3 months of neurological deficit. Also, it is observed that those patients with mild to moderate motor weakness show better recovery. Younger patients of less than 50 years with single level involvement show better recovery. We have observed preoperative muscle strength and duration of palsy as a significant prognostic indicator of better outcome following surgical lumbar decompression