Surgical treatment guided by spinal cord evoked potentials for tetraparesis due to cervical spondylosis.

Sixteen consecutive patients who were unable to ambulate independently due to cervical spondylotic myelopathy were treated surgically with the guidance of spinal cord evoked potentials (SCEPs). The SCEPs were recorded intraoperatively with needle electrodes inserted into serial cervical intervertebral discs after caudal epidural stimulation. Despite the presence of multiple extradural defects and/or cord compression seen on MRI, anterior decompression followed by fusion was able to be focused on a single level where the distinct change in waveform of the SCEP suggestive of spinal conduction block was revealed. Excellent neurological improvement resulted from the operation and all patients followed up for a period of more than 6 months were found to be ambulatory without walking aids.