Monomelic amyotrophy (MMA),is a rare benign disorder, also referred to as Hirayama's disease Juvenile non progressive amyotrophy, Sobue disease. It is a focal, lower motor neuron type of disease. Mainly young males in their second and third decades of age are most commonly affected. In majority of people cause of this disease is unknown. MRI of cervical spine in flexion will reveal the cardinal features of Hirayama disease.

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Dr Syed Imran

Third Year Post Graduate Department of General Medicine, Mediciti Institute of Medical Sciences, Ghanpur, Telangana