Hirayama disease, also known as Monomelic amyotrophy (MMA) is a focal motor neuron disease that primarily affects young males in the age group 15- to 25-year-old. MMA is marked by insidious onset of muscular atrophy, which stabilizes at a plateau after two to five years from which it neither improves nor worsens. There is no cure for MMA. Treatment consists of muscle strengthening exercises and training in hand coordination. Please see a Neurologist for further line of management. In case of further doubts, please feel free to write back to me. Regards Dr Prashik Meshram