Hirayama disease associated with a severe rhythmic movement disorder involving neck flexions

Abstract

Hirayama disease is a cervical myelopathy with teenage onset of unilateral or asymmetric weakness and atrophy of intrinsic hand and forearm muscles. It is initially progressive for several years but eventually stabilizes.1,2 Its pathophysiology is still debated: Most authors report evidence of dynamic cord compression during neck flexion,1–4 but others disagree with this terminology.5 We report on a 10-year-old girl with Hirayama disease who, since infancy, had had a severe and persistent nocturnal rhythmic movement disorder with extreme repeated neck flexions caused by body and head rocking in a prone position. The girl had a 10-month history of difficulty using her left hand while playing the clarinet and performing gymnastics, increasing when her hand was cold. She had no history of trauma, pain, paresthesias, or symptoms referring to the lower extremities and no family history of neurologic disease. On examination, she was a prepubertal girl with height in …