M18.2 — Bilateral post-traumatic osteoarthritis of first carpometacarpal joints
M18.2 is a billable, specific ICD-10-CM code for bilateral post-traumatic osteoarthritis of first carpometacarpal joints. It is valid for submission on a claim.
Other codes that can never be billed with M18.2
These codes carry an Excludes1 note pointing at M18.2. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading M18.2 alone.
- M12.5Traumatic arthropathy
Risk adjustment
M18.2 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
M18.2 is named in 11 Medicare coverage policies — 5 listing it as supporting medical necessity, and 6 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A58865Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A58893Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A59374Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A59434Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
How M18.2 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to M18.2.
- Osteoarthritis›post-traumatic NEC›hand joint›first carpometacarpal joint›bilateral
Related codes at this level
Codes that share M18. If M18.2 is not quite right, the correct code is usually one of these.
- M18.0Bilateral primary osteoarthritis of first carpometacarpal joints
- M18.1Unilateral primary osteoarthritis of first carpometacarpal joint
- M18.3Unilateral post-traumatic osteoarthritis of first carpometacarpal joint
- M18.4Other bilateral secondary osteoarthritis of first carpometacarpal joints
- M18.5Other unilateral secondary osteoarthritis of first carpometacarpal joint
- M18.9Osteoarthritis of first carpometacarpal joint, unspecified
Questions about M18.2
- Is M18.2 a billable ICD-10-CM code?
- Yes. M18.2 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does M18.2 sit in the tabular list?
- Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Osteoarthritis (M15-M19).