MOTOR AND SOMATOSENSORY CONDUCTION IN CERVICAL MYELOPATHY AND RADICULOPATHY

Study Design. Motor and sensory conduction times were measured in pati ents with cervical myelopathy and radiculopathy. The results were comp ared with those of control subjects. Objective, To evaluate the clinic al value of the combined use of motor-evoked potentials with F wave re cording and somatosensory-evoked potentials in cervical myelopathy and radiculopathy. Summary of Background Data, Electromyography and somat osensory-evoked potentials provide only indirect information on the mo tor pathways. The development of magnetic transcranial stimulation has provided a direct and reliable physiologic insight into the motor sys tem. Methods. Magnetic stimulation of the motor cortex and nerve roots with F wave recording was used to-assess central and peripheral motor conduction times. Somatosensory conduction was evaluated by somatosen sory-evoked potentials. Results. Significant prolongation of the centr al sensory and motor conduction times was found in the group with myel opathy. These findings were much more pronounced in patients who had m ultiple level spondylotic stenosis of the spinal canal than in those h arboring a single disc herniation compressing the spinal cord. In cont rast to somatosensory-evoked potentials, motor-evoked potentials combi ned with F wave recording showed marked impairment of peripheral condu ction in patients with radiculopathy. Conclusion. Motor-evoked potenti als associated with F wave recording was suitable for the evaluation o f patients with radiculopathy, The severity of conduction impairment i n patients with myelopathy can be assessed by combined motor-evoked po tentials and somatosensory-evoked potentials.