Hirayama Disease: Surgical Restoration of Hand Function.

ABSTRACT

PURPOSE: Hirayama disease (HD) is a rare, nonfamilial, self-limiting, progressive lower cervical myelopathy, resulting in debilitating distal upper-extremity motor deficits, mimicking high ulnar neuropathy, lower trunk brachial plexopathy, or C8-T1 radiculopathy. Although most literature focuses on pathophysiology and prevention of disease progression, there remains limited discussion regarding treatment to improve upper-extremity function in patients with stable disease. The upper-extremity manifestations of HD are reviewed along with surgical options for restoring hand function. METHODS: A retrospective review of patients with HD who underwent reconstruction to improve hand function was undertaken. Demographic data, preoperative electrodiagnostic and electromyographic, and physical examination findings were collected. Outcome data involved postoperative grip, pinch, and functional assessment documented on clinical visits. Qualitative descriptions of the surgical techniques are described. RESULTS: Among six patients identified, four met the inclusion criteria and underwent tendon transfers and selected joint arthrodeses. All patients were diagnosed as teenagers, were right hand-dominant, and three were male. Unilateral symptoms were present in one patient and were bilateral in the rest. All patients were treated with tendon transfers for thumb opposition, grasp, anticlaw, and thumb interphalangeal joint arthrodesis. All patients had postoperative grip strength improvement. The average follow-up was 3.2 years. CONCLUSIONS: Hirayama disease is a rare disease often managed by spine surgeons and neurologists who may be unaware of options for restoring hand function deficits. Technical strategies and outcomes of improving hand function in HD have not been adequately described. Surgical options to improve hand function are tailored to the deficits and include tendon transfers, select joint arthrodeses, and/or tenodeses. Risk of disease progression and expectations following hand reconstruction must be managed carefully. TYPE OF STUDY LEVEL OF EVIDENCE Therapeutic V.