RESUMO
To study the relationship between the electrodiagnostic and the MRI findings of the lumbar spine and to correlate them to the clinical features in patients with degenerative lumbar spinal stenosis [LSS]. Fifty-six patients diagnosed as having LSS, on the basis of typical clinical features and compatible MRI findings, were included in this study. In addition to history and examination, patients were assessed for disease severity using the maximal walking distance and the visual analogue scale. MRI parameters of lumbar spinal stenosis were assessed. Needle electromyography of the paraspinal muscles and nerve conduction studies including F-wave and H-reflex were performed. Patients were 33 males and 23 females. The body mass index statistically significantly correlated with the patient scores on the visual analogue scale. No significant relation could be detected between age, sex, duration of disease and disease severity. Both of the smallest and the smallest two anteroposterior spinal canal diameters showed no statistical significant correlation with the disease severity. The fibrillations in electromyographic testing statistically highly significantly [p<0.001] negatively correlated with the maximal walking distance and positively correlated with the patient scores on the visual analogue scale. It also statistically highly significantly correlated with the age. MRI findings are related to the diagnosis but not to severity ot the clinical lumbar spinal stenosis. Electrophysiologic studies especially paraspinal muscles denervation potentials seem to be a more sensitive criterion in assessing the severity of symptoms in patients with LSS