Motor and somatosensory conduction time between the cortex and the Erb point in patients suffering from cervical spinal stenosis and tumour.

Motor and sensory conduction time between the cortex and the Erb point were examined in patients with cervical cord compression. Patients were divided into two groups: the compression was caused either by cervical extramedullary tumour (9 cases), or by cervical spondylosis or herniated disc (16 cases). In response to median nerve stimulation, pathological somatosensory evoked potentials were recorded in 66% of the patients suffering from tumour and in 60% of the patients suffering from spondylosis. All of the patients disclosed pathological motor evoked potentials. On the basis of these observations it could be concluded that, in cases of cervical spinal cord compression, the involvement of the motor system could be more reliably detected than that of the sensory system with electrophysiological methods.