ICD-10-CM > M00-M99 > M60-M63 > M62 > M62.5 > M62.53 M62.53 Muscle wasting and atrophy, not elsewhere classified, forearm Non-Billable/Non-Specific Codes M62.531Muscle wasting and atrophy, not elsewhere classified, right forearmM62.532Muscle wasting and atrophy, not elsewhere classified, left forearmM62.539Muscle wasting and atrophy, not elsewhere classified, unspecified forearm