Hereditary neuralgic amyotrophy (HNA) is a neuralgic disorder that is characterized by nerve damage and muscle atrophy, preceded by severe pain.[1] In about half of the cases it is associated with a mutation of the SEPT9 gene (17q25). While not much is known about this disorder, it has been characterized to be similar to Parsonage-Turner syndrome in prognosis.

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Wiki: Hereditary neuralgic amyotrophy