Clinical, radiological, and functional evaluation of surgical treatment in degenerative lumbar canal stenosis

Background: Lumbar spinal stenosis is a frequent indication for spinal surgery. The clinical symptoms may not be accurately reflected on radiological studies. Treatment is aimed at not only obtaining immediate pain relief but also in preventing its long-term disabling sequelae. The walking ability needs to be correlated with functional outcome measures in assessing patients with symptomatic lumbar canal stenosis (LCS). Aims and Objectives: To study and evaluate the outcome of surgery for degenerative LCS on a clinical, radiological, and functional basis, and to establish an association between various factors that may be influencing the development of LCS. Materials and Methods: A prospective study of 48 patients was carried out at the Department of Neurosurgery, Sri Venkateswara Institute of Medical Sciences, Tirupathi, in whom the LCS was confirmed and measured on magnetic resonance imaging images by thecal sac cross-sectional area (CSA). Their functional assessment was done by motorized treadmill test for assessment of the time of appearance of first symptom and the maximum walking distance. The visual analog scale (VAS), Oswestry disability index (ODI), Japanese Orthopedic Association (JOA) score, and Short Form-36 (SF-36) score were also evaluated. Conclusions: The post-operative VAS, ODI, JOA, SF-36 scores showed a significant improvement from the preoperative ones. Postoperative thecal sac measurements showed a significant neural decompression substantiating the results of improvement in the functional assessment scores after surgery. The treadmill test is a quantifiable means of dynamic function. It may be considered as a useful tool for the assessment of functional impairment and for the correlation of thecal sac CSA with lumbar canal stenosis. A combination of functional scores, treadmill test, and thecal sac CSA may be included in the preoperative assessment of outcome in patients with LCS.