Is Hirayama a Gq1b disease?

Excerpt

Hirayama disease (HD) or juvenile muscular atrophy of distal upper extremity is a rare benign disease of motor neurons that commonly affects the cervical spinal segments. It is more prevalent in males and mostly seen in teens and early 20s. Slowly progressive unilateral or asymmetrically bilateral weakness of hands and forearms is typical. Sensory disturbances, autonomic and upper motor neuron signs are extremely rare [1]. As the synonym “benign focal amyotrophy” implies, it reaches a plateau after a few years. Electromyography reveals asymmetrical chronic denervation in C7, C8, and T1 myotomes. Preservation of C6 myotomes is remarkable. Supportive MRI findings are anterior shift of posterior dura, enlargement of epidural space, and venous congestion under neck flexion. …