ICD-10 · PDGM grouping
M13 Other arthritis
All 47 codes in the M13 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
ICD-10-CM FY2027 · CMS grouper v07.2.26
Codes in family
47
Can lead a claim
33
Cannot lead a claim
14
What CMS assigns to M13
33 of the 47 codes group to Musculoskeletal Rehabilitation; 14 are assigned no clinical group. None of the 47 is assigned a comorbidity subgroup. 33 of the 47 can lead a claim.
Every code in M13
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| M13.0 | Polyarthritis, unspecified | Can lead a claim | E | None |
| M13.1 Monoarthritis, not elsewhere classified | ||||
| M13.10 | Monoarthritis, not elsewhere classified, unspecified site | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.11 Monoarthritis, not elsewhere classified, shoulder | ||||
| M13.111 | Monoarthritis, not elsewhere classified, right shoulder | Can lead a claim | E | None |
| M13.112 | Monoarthritis, not elsewhere classified, left shoulder | Can lead a claim | E | None |
| M13.119 | Monoarthritis, not elsewhere classified, unspecified shoulderCMS: Monoarthritis, not elsewhere classified, unsp shoulder | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.12 Monoarthritis, not elsewhere classified, elbow | ||||
| M13.121 | Monoarthritis, not elsewhere classified, right elbow | Can lead a claim | E | None |
| M13.122 | Monoarthritis, not elsewhere classified, left elbow | Can lead a claim | E | None |
| M13.129 | Monoarthritis, not elsewhere classified, unspecified elbow | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.13 Monoarthritis, not elsewhere classified, wrist | ||||
| M13.131 | Monoarthritis, not elsewhere classified, right wrist | Can lead a claim | E | None |
| M13.132 | Monoarthritis, not elsewhere classified, left wrist | Can lead a claim | E | None |
| M13.139 | Monoarthritis, not elsewhere classified, unspecified wrist | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.14 Monoarthritis, not elsewhere classified, hand | ||||
| M13.141 | Monoarthritis, not elsewhere classified, right hand | Can lead a claim | E | None |
| M13.142 | Monoarthritis, not elsewhere classified, left hand | Can lead a claim | E | None |
| M13.149 | Monoarthritis, not elsewhere classified, unspecified hand | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.15 Monoarthritis, not elsewhere classified, hip | ||||
| M13.151 | Monoarthritis, not elsewhere classified, right hip | Can lead a claim | E | None |
| M13.152 | Monoarthritis, not elsewhere classified, left hip | Can lead a claim | E | None |
| M13.159 | Monoarthritis, not elsewhere classified, unspecified hip | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.16 Monoarthritis, not elsewhere classified, knee | ||||
| M13.161 | Monoarthritis, not elsewhere classified, right knee | Can lead a claim | E | None |
| M13.162 | Monoarthritis, not elsewhere classified, left knee | Can lead a claim | E | None |
| M13.169 | Monoarthritis, not elsewhere classified, unspecified knee | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.17 Monoarthritis, not elsewhere classified, ankle and foot | ||||
| M13.171 | Monoarthritis, not elsewhere classified, right ankle and footCMS: Monoarthritis, NEC, right ankle and foot | Can lead a claim | E | None |
| M13.172 | Monoarthritis, not elsewhere classified, left ankle and foot | Can lead a claim | E | None |
| M13.179 | Monoarthritis, not elsewhere classified, unspecified ankle and footCMS: Monoarthritis, not elsewhere classified, unsp ankle and foot | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.8 Other specified arthritis | ||||
| M13.80 | Other specified arthritis, unspecified site | Can lead a claim | E | None |
| M13.81 Other specified arthritis, shoulder | ||||
| M13.811 | Other specified arthritis, right shoulder | Can lead a claim | E | None |
| M13.812 | Other specified arthritis, left shoulder | Can lead a claim | E | None |
| M13.819 | Other specified arthritis, unspecified shoulder | Can lead a claim | E | None |
| M13.82 Other specified arthritis, elbow | ||||
| M13.821 | Other specified arthritis, right elbow | Can lead a claim | E | None |
| M13.822 | Other specified arthritis, left elbow | Can lead a claim | E | None |
| M13.829 | Other specified arthritis, unspecified elbow | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.83 Other specified arthritis, wrist | ||||
| M13.831 | Other specified arthritis, right wrist | Can lead a claim | E | None |
| M13.832 | Other specified arthritis, left wrist | Can lead a claim | E | None |
| M13.839 | Other specified arthritis, unspecified wrist | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.84 Other specified arthritis, hand | ||||
| M13.841 | Other specified arthritis, right hand | Can lead a claim | E | None |
| M13.842 | Other specified arthritis, left hand | Can lead a claim | E | None |
| M13.849 | Other specified arthritis, unspecified hand | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.85 Other specified arthritis, hip | ||||
| M13.851 | Other specified arthritis, right hip | Can lead a claim | E | None |
| M13.852 | Other specified arthritis, left hip | Can lead a claim | E | None |
| M13.859 | Other specified arthritis, unspecified hip | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.86 Other specified arthritis, knee | ||||
| M13.861 | Other specified arthritis, right knee | Can lead a claim | E | None |
| M13.862 | Other specified arthritis, left knee | Can lead a claim | E | None |
| M13.869 | Other specified arthritis, unspecified knee | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.87 Other specified arthritis, ankle and foot | ||||
| M13.871 | Other specified arthritis, right ankle and foot | Can lead a claim | E | None |
| M13.872 | Other specified arthritis, left ankle and foot | Can lead a claim | E | None |
| M13.879 | Other specified arthritis, unspecified ankle and foot | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M13.88 | Other specified arthritis, other site | Can lead a claim | E | None |
| M13.89 | Other specified arthritis, multiple sites | Can lead a claim | E | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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