Cervical myelopathy: clinical and neurophysiological evaluation.

The overall frequency of troublesome neck pain is estimated to be about 34%, and it was observed that the frequency of complaints lasting 1 month or longer was higher in women than in men. The prevalence increased with age, with regard to both pain duration and chronic pain. Approximately 14% of a randomly selected population meets the criterion for chronic neck pain: complaints lasting more than 6 months. Epidemiologic data substantiate the importance of morphologic, age-related changes of the cervical spine; however, the incidence and prevalence of cervical myelopathy is not known. It could be that the structural transformation of the intervertebral disc, the uncovertebral processes and the zygapophyseal joints is a process accompanied by disturbed function that ultimately not only induces pain, but can lead to narrowing of spinal canal, with symptoms and signs of cervical myelopathy. For a diagnosis of radicular and myelopathic syndromes, the functional and neurological examination is enhanced by neurophysiological assessment. Electromyography (EMG) performed with needle electrodes is the oldest method for diagnosing nerve root compression and anterior horn cell syndromes, and is claimed to have no false-positive results. For cervical myelopathy, as a routine examination sensory evoked potentials (SEPs) by stimulation of tibial nerve and motor evoked potentials (MEPs) from the upper and lower extremities are recommended.