A quantitative evaluation of sensory dysfunction in lumbosacral radiculopathy.

A quantitative evaluation of sensory disturbance of the foot was attempted in 94 cases of lumbosacral radiculopathy using the biothesiometer, the Semmes-Weinstein esthesiometer, light touch, tuning fork, and dermatomal somatosensory evoked potentials. Dermatomal somatosensory evoked potentials was the most sensitive of these tests, and reflected the duration of the lumbosacral radiculopathy better than the biothesiometer and the Semmes-Weinstein esthesiometer. The biothesiometer and Semmes-Weinstein esthesiometer reflected the clinical severity of sensory dysfunctions, the extent of numbness, and the immediate change in sensory function better than the dermatomal somatosensory evoked potentials. It is important to understand the characteristics of each test and to choose informative tests for clinical use. Grades of sensory disturbance in patients with lumbosacral radiculopathy were classified into three categories in combination with the findings of dermatomal somatosensory evoked potentials and the values recorded with the biothesiometer and Semmes-Weinstein esthesiometer.