The importance of paraspinal muscle EMG in cervical and lumbosacral radiculopathy: review of 100 cases.

It is well known that examination of the paraspinal muscles are an important part of the electrodiagnostic (EDX) evaluation of a patient with suspected radiculopathy. However, many electromyographers hesitate to routinely include this in their study. A random retrospective chart review was performed on 49 patients with cervical radiculopathy and 51 patients with lumbosacral radiculopathy to determine the frequency of EDX abnormalities in the paraspinal muscles and limb muscles. Criteria for abnormality was the presence of spontaneous activity in two muscles in a myotomal pattern in the limb, or in the paraspinal muscles. It was found that 20 out of 49 (40.8%) of the cervical radiculopathies and 10 out of 51 (19.6%) of the lumbosacral radiculopathies had abnormalities restricted only to the paraspinal muscles. These results indicate that especially in the cervical spine, a significant percentage of patients with radiculopathy will be missed if examination of the paraspinal muscles are not part of the EDX evaluation of the patient with suspected radiculopathy.