Hand wasting in spondylotic high cord compression: an electromyographic study.

Conventional and single-fiber electromyographic studies in two patients with a wasted hand associated with spondylotic narrowing of the spinal canal at C3-4 and C5-6 revealed changes that were most severe in the hand muscles (C8, T1) and moderately severe in the extensor digitorum communis (C7), but relatively spared the C5 and C6 myotomes. This gradation of abnormality within the cervical cord is consistent with stagnant hypoxia secondary to venous congestion.