Hirayama disease. Clinical cases

Abstract

Hirayama disease, or monomelic amyotrophy, is a rare neurological pathology manifested by unilateral or bilateral asymmetric paresis with atrophy of the distal upper extremities. The development of this disease is associated with the forward displacement of the posterior dural sac during neck flexion, which leads to compression of the spinal cord and venous stasis. The diagnosis of monomelic amyotrophy is based on the clinical picture and the results of magnetic resonance imaging of the cervical spine with flexion, showing segmental atrophy of the anterior horns of the spinal cord at C7 — Th1, detachment of the posterior dura mater and venous stasis. Most of the cases described in the literature are from India and Japan, with isolated cases diagnosed in North America and Europe. This article presents two clinical cases of progressive hand weakness in young men. The clinical picture of the disease and the results of additional examination methods are presented, which is necessary to establish a diagnosis of Hirayama’s disease.