| M13 | Other arthritis | NON-BILLABLE CODE |
| M13.0 | Polyarthritis, unspecified | BILLABLE CODE |
| M13.1 | Monoarthritis, not elsewhere classified | NON-BILLABLE CODE |
| M13.10 | Monoarthritis, not elsewhere classified, unspecified site | BILLABLE CODE |
| M13.11 | Monoarthritis, not elsewhere classified, shoulder | NON-BILLABLE CODE |
| M13.111 | Monoarthritis, not elsewhere classified, right shoulder | BILLABLE CODE |
| M13.112 | Monoarthritis, not elsewhere classified, left shoulder | BILLABLE CODE |
| M13.119 | Monoarthritis, not elsewhere classified, unspecified shoulder | BILLABLE CODE |
| M13.12 | Monoarthritis, not elsewhere classified, elbow | NON-BILLABLE CODE |
| M13.121 | Monoarthritis, not elsewhere classified, right elbow | BILLABLE CODE |
| M13.122 | Monoarthritis, not elsewhere classified, left elbow | BILLABLE CODE |
| M13.129 | Monoarthritis, not elsewhere classified, unspecified elbow | BILLABLE CODE |
| M13.13 | Monoarthritis, not elsewhere classified, wrist | NON-BILLABLE CODE |
| M13.131 | Monoarthritis, not elsewhere classified, right wrist | BILLABLE CODE |
| M13.132 | Monoarthritis, not elsewhere classified, left wrist | BILLABLE CODE |
| M13.139 | Monoarthritis, not elsewhere classified, unspecified wrist | BILLABLE CODE |
| M13.14 | Monoarthritis, not elsewhere classified, hand | NON-BILLABLE CODE |
| M13.141 | Monoarthritis, not elsewhere classified, right hand | BILLABLE CODE |
| M13.142 | Monoarthritis, not elsewhere classified, left hand | BILLABLE CODE |
| M13.149 | Monoarthritis, not elsewhere classified, unspecified hand | BILLABLE CODE |
| M13.15 | Monoarthritis, not elsewhere classified, hip | NON-BILLABLE CODE |
| M13.151 | Monoarthritis, not elsewhere classified, right hip | BILLABLE CODE |
| M13.152 | Monoarthritis, not elsewhere classified, left hip | BILLABLE CODE |
| M13.159 | Monoarthritis, not elsewhere classified, unspecified hip | BILLABLE CODE |
| M13.16 | Monoarthritis, not elsewhere classified, knee | NON-BILLABLE CODE |
| M13.161 | Monoarthritis, not elsewhere classified, right knee | BILLABLE CODE |
| M13.162 | Monoarthritis, not elsewhere classified, left knee | BILLABLE CODE |
| M13.169 | Monoarthritis, not elsewhere classified, unspecified knee | BILLABLE CODE |
| M13.17 | Monoarthritis, not elsewhere classified, ankle and foot | NON-BILLABLE CODE |
| M13.171 | Monoarthritis, not elsewhere classified, right ankle and foot | BILLABLE CODE |
| M13.172 | Monoarthritis, not elsewhere classified, left ankle and foot | BILLABLE CODE |
| M13.179 | Monoarthritis, not elsewhere classified, unspecified ankle and foot | BILLABLE CODE |
| M13.8 | Other specified arthritis | NON-BILLABLE CODE |
| M13.80 | Other specified arthritis, unspecified site | BILLABLE CODE |
| M13.81 | Other specified arthritis, shoulder | NON-BILLABLE CODE |
| M13.811 | Other specified arthritis, right shoulder | BILLABLE CODE |
| M13.812 | Other specified arthritis, left shoulder | BILLABLE CODE |
| M13.819 | Other specified arthritis, unspecified shoulder | BILLABLE CODE |
| M13.82 | Other specified arthritis, elbow | NON-BILLABLE CODE |
| M13.821 | Other specified arthritis, right elbow | BILLABLE CODE |
| M13.822 | Other specified arthritis, left elbow | BILLABLE CODE |
| M13.829 | Other specified arthritis, unspecified elbow | BILLABLE CODE |
| M13.83 | Other specified arthritis, wrist | NON-BILLABLE CODE |
| M13.831 | Other specified arthritis, right wrist | BILLABLE CODE |
| M13.832 | Other specified arthritis, left wrist | BILLABLE CODE |
| M13.839 | Other specified arthritis, unspecified wrist | BILLABLE CODE |
| M13.84 | Other specified arthritis, hand | NON-BILLABLE CODE |
| M13.841 | Other specified arthritis, right hand | BILLABLE CODE |
| M13.842 | Other specified arthritis, left hand | BILLABLE CODE |
| M13.85 | Other specified arthritis, hip | NON-BILLABLE CODE |
| M13.851 | Other specified arthritis, right hip | BILLABLE CODE |
| M13.852 | Other specified arthritis, left hip | BILLABLE CODE |
| M13.859 | Other specified arthritis, unspecified hip | BILLABLE CODE |
| M13.86 | Other specified arthritis, knee | NON-BILLABLE CODE |
| M13.861 | Other specified arthritis, right knee | BILLABLE CODE |
| M13.862 | Other specified arthritis, left knee | BILLABLE CODE |
| M13.869 | Other specified arthritis, unspecified knee | BILLABLE CODE |
| M13.87 | Other specified arthritis, ankle and foot | NON-BILLABLE CODE |
| M13.871 | Other specified arthritis, right ankle and foot | BILLABLE CODE |
| M13.872 | Other specified arthritis, left ankle and foot | BILLABLE CODE |
| M13.879 | Other specified arthritis, unspecified ankle and foot | BILLABLE CODE |
| M13.88 | Other specified arthritis, other site | BILLABLE CODE |
| M13.89 | Other specified arthritis, multiple sites | BILLABLE CODE |
