Dissociation between intact vibratory sensation and impaired joint position sensation may predict ataxia of spinal origin

Vibratory and joint position sensations are usually impaired simultaneously and afferents for both sensations ascend the dorsal columns. There are a few evidences that the central pathways in the spinal cord for position and vibratory sensations are not identical. In this study, we examined the clinical features of patients with sensory impairments of vibratory and joint position sensations. According to 43 evaluated patients' results, the dissociation between an intact vibratory sensation and impaired joint position sensation may be important for the diagnosis of spinal disorders. We also report three cases of patients with spinal ataxia caused by sensory impairments and who show the dissociation between an impaired joint position sensation and an intact vibratory sensation. The combination of intact vibration sensation and impaired joint position sensation may suggest a dorsal column lesion in the spinal cord.