Short-latency somatosensory evoked potentials in the management of patients with achondroplasia.

Twenty-three patients with achondroplasia were evaluated using short-latency somatosensory evoked potentials (SEPs) of median and peroneal nerves. Abnormal studies were found in 61%. All patients with neurologic signs or symptoms had abnormal SEPs, with good correlation between SEP results and the level of the lesion determined clinically and radiographically. SEPs were abnormal in 44% of neurologically intact achondroplasts, several of whom had CTs confirming significant foramen magnum stenosis. SEPs are an important noninvasive means of evaluating patients with achondroplasia and are particularly valuable in children to document neurologic compromise before significant and perhaps irreversible clinical impairment develops.