Cervical cord tethering mimicking focal muscular atrophy.

Spinal cord tethering rarely occurs in the cervical region. In adults, it usually results from previous operations. However, congenital origin is always diagnosed and treated early in the infant period. We report a 12-year-old boy with cervical spinal dysraphism which was erroneously diagnosed as focal muscular atrophy, a benign form of motor neuron disease. The patient was brought to our hospital because of rapid deterioration of symptoms. Careful evaluation disclosed a hairy dimple at the nuchal area, which led to the correct diagnosis. X-ray of the cervical spine showed spina bifida from C(4) to C(6) levels and fusion of the laminae of C(4) and C(5). Spine MRI studies disclosed that the cervical cord was tethered caudally and dorsally, and the ventral nerve roots were markedly stretched, especially over the left side. Surgical intervention was undertaken and the patient's muscle power improved after untethering. The purpose of this report is to acquaint the reader with a surgically treatable condition that may appear to be benign focal amyotrophy. Skin lesion at the nuchal area should be carefully looked for.