ICD-10 · PDGM grouping
M66 Spontaneous rupture of synovium and tendon
All 103 codes in the M66 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
103
Can lead a claim
68
Cannot lead a claim
35
What CMS assigns to M66
68 of the 103 codes group to Musculoskeletal Rehabilitation; 35 are assigned no clinical group. None of the 103 is assigned a comorbidity subgroup. 68 of the 103 can lead a claim.
Every code in M66
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 |
|---|---|---|---|---|
| M66.0 | Rupture of popliteal cyst | Can lead a claim | E | None |
| M66.1 Rupture of synovium | ||||
| M66.10 | Rupture of synovium, unspecified joint | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.11 Rupture of synovium, shoulder | ||||
| M66.111 | Rupture of synovium, right shoulder | Can lead a claim | E | None |
| M66.112 | Rupture of synovium, left shoulder | Can lead a claim | E | None |
| M66.119 | Rupture of synovium, unspecified shoulder | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.12 Rupture of synovium, elbow | ||||
| M66.121 | Rupture of synovium, right elbow | Can lead a claim | E | None |
| M66.122 | Rupture of synovium, left elbow | Can lead a claim | E | None |
| M66.129 | Rupture of synovium, unspecified elbow | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.13 Rupture of synovium, wrist | ||||
| M66.131 | Rupture of synovium, right wrist | Can lead a claim | E | None |
| M66.132 | Rupture of synovium, left wrist | Can lead a claim | E | None |
| M66.139 | Rupture of synovium, unspecified wrist | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.14 Rupture of synovium, hand and fingers | ||||
| M66.141 | Rupture of synovium, right hand | Can lead a claim | E | None |
| M66.142 | Rupture of synovium, left hand | Can lead a claim | E | None |
| M66.143 | Rupture of synovium, unspecified hand | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.144 | Rupture of synovium, right finger(s) | Can lead a claim | E | None |
| M66.145 | Rupture of synovium, left finger(s) | Can lead a claim | E | None |
| M66.146 | Rupture of synovium, unspecified finger(s) | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.15 Rupture of synovium, hip | ||||
| M66.151 | Rupture of synovium, right hip | Can lead a claim | E | None |
| M66.152 | Rupture of synovium, left hip | Can lead a claim | E | None |
| M66.159 | Rupture of synovium, unspecified hip | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.17 Rupture of synovium, ankle, foot and toes | ||||
| M66.171 | Rupture of synovium, right ankle | Can lead a claim | E | None |
| M66.172 | Rupture of synovium, left ankle | Can lead a claim | E | None |
| M66.173 | Rupture of synovium, unspecified ankle | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.174 | Rupture of synovium, right foot | Can lead a claim | E | None |
| M66.175 | Rupture of synovium, left foot | Can lead a claim | E | None |
| M66.176 | Rupture of synovium, unspecified foot | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.177 | Rupture of synovium, right toe(s) | Can lead a claim | E | None |
| M66.178 | Rupture of synovium, left toe(s) | Can lead a claim | E | None |
| M66.179 | Rupture of synovium, unspecified toe(s) | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.18 | Rupture of synovium, other site | Can lead a claim | E | None |
| M66.2 Spontaneous rupture of extensor tendons | ||||
| M66.20 | Spontaneous rupture of extensor tendons, unspecified site | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.21 Spontaneous rupture of extensor tendons, shoulder | ||||
| M66.211 | Spontaneous rupture of extensor tendons, right shoulder | Can lead a claim | E | None |
| M66.212 | Spontaneous rupture of extensor tendons, left shoulder | Can lead a claim | E | None |
| M66.219 | Spontaneous rupture of extensor tendons, unspecified shoulderCMS: Spontaneous rupture of extensor tendons, unsp shoulder | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.22 Spontaneous rupture of extensor tendons, upper arm | ||||
| M66.221 | Spontaneous rupture of extensor tendons, right upper arm | Can lead a claim | E | None |
| M66.222 | Spontaneous rupture of extensor tendons, left upper arm | Can lead a claim | E | None |
| M66.229 | Spontaneous rupture of extensor tendons, unspecified upper armCMS: Spontaneous rupture of extensor tendons, unsp upper arm | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.23 Spontaneous rupture of extensor tendons, forearm | ||||
| M66.231 | Spontaneous rupture of extensor tendons, right forearm | Can lead a claim | E | None |
| M66.232 | Spontaneous rupture of extensor tendons, left forearm | Can lead a claim | E | None |
| M66.239 | Spontaneous rupture of extensor tendons, unspecified forearm | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.24 Spontaneous rupture of extensor tendons, hand | ||||
| M66.241 | Spontaneous rupture of extensor tendons, right hand | Can lead a claim | E | None |
| M66.242 | Spontaneous rupture of extensor tendons, left hand | Can lead a claim | E | None |
| M66.249 | Spontaneous rupture of extensor tendons, unspecified hand | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.25 Spontaneous rupture of extensor tendons, thigh | ||||
| M66.251 | Spontaneous rupture of extensor tendons, right thigh | Can lead a claim | E | None |
| M66.252 | Spontaneous rupture of extensor tendons, left thigh | Can lead a claim | E | None |
| M66.259 | Spontaneous rupture of extensor tendons, unspecified thigh | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.26 Spontaneous rupture of extensor tendons, lower leg | ||||
| M66.261 | Spontaneous rupture of extensor tendons, right lower leg | Can lead a claim | E | None |
| M66.262 | Spontaneous rupture of extensor tendons, left lower leg | Can lead a claim | E | None |
| M66.269 | Spontaneous rupture of extensor tendons, unspecified lower legCMS: Spontaneous rupture of extensor tendons, unsp lower leg | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.27 Spontaneous rupture of extensor tendons, ankle and foot | ||||
| M66.271 | Spontaneous rupture of extensor tendons, right ankle and footCMS: Spontaneous rupture of extensor tendons, right ank/ft | Can lead a claim | E | None |
| M66.272 | Spontaneous rupture of extensor tendons, left ankle and foot | Can lead a claim | E | None |
| M66.279 | Spontaneous rupture of extensor tendons, unspecified ankle and footCMS: Spontaneous rupture of extensor tendons, unsp ankle and foot | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.28 | Spontaneous rupture of extensor tendons, other site | Can lead a claim | E | None |
| M66.29 | Spontaneous rupture of extensor tendons, multiple sites | Can lead a claim | E | None |
| M66.3 Spontaneous rupture of flexor tendons | ||||
| M66.30 | Spontaneous rupture of flexor tendons, unspecified site | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.31 Spontaneous rupture of flexor tendons, shoulder | ||||
| M66.311 | Spontaneous rupture of flexor tendons, right shoulder | Can lead a claim | E | None |
| M66.312 | Spontaneous rupture of flexor tendons, left shoulder | Can lead a claim | E | None |
| M66.319 | Spontaneous rupture of flexor tendons, unspecified shoulder | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.32 Spontaneous rupture of flexor tendons, upper arm | ||||
| M66.321 | Spontaneous rupture of flexor tendons, right upper arm | Can lead a claim | E | None |
| M66.322 | Spontaneous rupture of flexor tendons, left upper arm | Can lead a claim | E | None |
| M66.329 | Spontaneous rupture of flexor tendons, unspecified upper arm | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.33 Spontaneous rupture of flexor tendons, forearm | ||||
| M66.331 | Spontaneous rupture of flexor tendons, right forearm | Can lead a claim | E | None |
| M66.332 | Spontaneous rupture of flexor tendons, left forearm | Can lead a claim | E | None |
| M66.339 | Spontaneous rupture of flexor tendons, unspecified forearm | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.34 Spontaneous rupture of flexor tendons, hand | ||||
| M66.341 | Spontaneous rupture of flexor tendons, right hand | Can lead a claim | E | None |
| M66.342 | Spontaneous rupture of flexor tendons, left hand | Can lead a claim | E | None |
| M66.349 | Spontaneous rupture of flexor tendons, unspecified hand | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.35 Spontaneous rupture of flexor tendons, thigh | ||||
| M66.351 | Spontaneous rupture of flexor tendons, right thigh | Can lead a claim | E | None |
| M66.352 | Spontaneous rupture of flexor tendons, left thigh | Can lead a claim | E | None |
| M66.359 | Spontaneous rupture of flexor tendons, unspecified thigh | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.36 Spontaneous rupture of flexor tendons, lower leg | ||||
| M66.361 | Spontaneous rupture of flexor tendons, right lower leg | Can lead a claim | E | None |
| M66.362 | Spontaneous rupture of flexor tendons, left lower leg | Can lead a claim | E | None |
| M66.369 | Spontaneous rupture of flexor tendons, unspecified lower leg | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.37 Spontaneous rupture of flexor tendons, ankle and foot | ||||
| M66.371 | Spontaneous rupture of flexor tendons, right ankle and foot | Can lead a claim | E | None |
| M66.372 | Spontaneous rupture of flexor tendons, left ankle and foot | Can lead a claim | E | None |
| M66.379 | Spontaneous rupture of flexor tendons, unspecified ankle and footCMS: Spontaneous rupture of flexor tendons, unsp ankle and foot | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.38 | Spontaneous rupture of flexor tendons, other site | Can lead a claim | E | None |
| M66.39 | Spontaneous rupture of flexor tendons, multiple sites | Can lead a claim | E | None |
| M66.8 Spontaneous rupture of other tendons | ||||
| M66.80 | Spontaneous rupture of other tendons, unspecified site | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.81 Spontaneous rupture of other tendons, shoulder | ||||
| M66.811 | Spontaneous rupture of other tendons, right shoulder | Can lead a claim | E | None |
| M66.812 | Spontaneous rupture of other tendons, left shoulder | Can lead a claim | E | None |
| M66.819 | Spontaneous rupture of other tendons, unspecified shoulder | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.82 Spontaneous rupture of other tendons, upper arm | ||||
| M66.821 | Spontaneous rupture of other tendons, right upper arm | Can lead a claim | E | None |
| M66.822 | Spontaneous rupture of other tendons, left upper arm | Can lead a claim | E | None |
| M66.829 | Spontaneous rupture of other tendons, unspecified upper arm | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.83 Spontaneous rupture of other tendons, forearm | ||||
| M66.831 | Spontaneous rupture of other tendons, right forearm | Can lead a claim | E | None |
| M66.832 | Spontaneous rupture of other tendons, left forearm | Can lead a claim | E | None |
| M66.839 | Spontaneous rupture of other tendons, unspecified forearm | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.84 Spontaneous rupture of other tendons, hand | ||||
| M66.841 | Spontaneous rupture of other tendons, right hand | Can lead a claim | E | None |
| M66.842 | Spontaneous rupture of other tendons, left hand | Can lead a claim | E | None |
| M66.849 | Spontaneous rupture of other tendons, unspecified hand | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.85 Spontaneous rupture of other tendons, thigh | ||||
| M66.851 | Spontaneous rupture of other tendons, right thigh | Can lead a claim | E | None |
| M66.852 | Spontaneous rupture of other tendons, left thigh | Can lead a claim | E | None |
| M66.859 | Spontaneous rupture of other tendons, unspecified thigh | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.86 Spontaneous rupture of other tendons, lower leg | ||||
| M66.861 | Spontaneous rupture of other tendons, right lower leg | Can lead a claim | E | None |
| M66.862 | Spontaneous rupture of other tendons, left lower leg | Can lead a claim | E | None |
| M66.869 | Spontaneous rupture of other tendons, unspecified lower leg | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.87 Spontaneous rupture of other tendons, ankle and foot | ||||
| M66.871 | Spontaneous rupture of other tendons, right ankle and foot | Can lead a claim | E | None |
| M66.872 | Spontaneous rupture of other tendons, left ankle and foot | Can lead a claim | E | None |
| M66.879 | Spontaneous rupture of other tendons, unspecified ankle and footCMS: Spontaneous rupture of other tendons, unsp ankle and foot | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M66.88 | Spontaneous rupture of other tendons, other sites | Can lead a claim | E | None |
| M66.89 | Spontaneous rupture of other tendons, multiple sites | Can lead a claim | E | None |
| M66.9 | Spontaneous rupture of unspecified tendon | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | 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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