M60.12 Interstitial myositis, upper armNon-billable header with 3 child codes.
M60.121 Interstitial myositis, right upper armM60.122 Interstitial myositis, left upper armM60.129 Interstitial myositis, unspecified upper armG71 Primary disorders of muscles ("myositis (M60.-)")G72 Other and unspecified myopathies ("myositis (M60.-)")M79.1 Myalgia ("myositis (M60.-)")M60.10 Interstitial myositis of unspecified siteM60.11 Interstitial myositis, shoulderM60.111 Interstitial myositis, right shoulderM60.112 Interstitial myositis, left shoulderM60.119 Interstitial myositis, unspecified shoulderM60.12 Interstitial myositis, upper arm (this code)M60.121 Interstitial myositis, right upper armM60.122 Interstitial myositis, left upper armM60.129 Interstitial myositis, unspecified upper armM60.13 Interstitial myositis, forearmM60.131 Interstitial myositis, right forearm