M13.1 Monoarthritis, not elsewhere classifiedNon-billable header with 8 child codes.
M13.10 Monoarthritis, not elsewhere classified, unspecified siteM13.11 Monoarthritis, not elsewhere classified, shoulderM13.12 Monoarthritis, not elsewhere classified, elbowM13.13 Monoarthritis, not elsewhere classified, wristM13.14 Monoarthritis, not elsewhere classified, handM13.15 Monoarthritis, not elsewhere classified, hipM13.16 Monoarthritis, not elsewhere classified, kneeM13.17 Monoarthritis, not elsewhere classified, ankle and footM13 Other arthritisM13.0 Polyarthritis, unspecifiedM13.1 Monoarthritis, not elsewhere classified (this code)M13.10 Monoarthritis, not elsewhere classified, unspecified siteM13.11 Monoarthritis, not elsewhere classified, shoulderM13.111 Monoarthritis, not elsewhere classified, right shoulderM13.112 Monoarthritis, not elsewhere classified, left shoulderM13.119 Monoarthritis, not elsewhere classified, unspecified shoulder