M18.3 — Unilateral post-traumatic osteoarthritis of first carpometacarpal joint
M18.3 is a non-billable header ICD-10-CM code for unilateral post-traumatic osteoarthritis of first carpometacarpal joint. It cannot be billed on its own: choose one of the more specific child codes below.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Post-traumatic osteoarthritis of first carpometacarpal joint NOS
Other codes that can never be billed with M18.3
These codes carry an Excludes1 note pointing at M18.3. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading M18.3 alone.
- M12.5Traumatic arthropathy
Risk adjustment
M18.3 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.
Code to one of these instead M18.3
3 child codes. Green means billable.
Related codes at this level
Codes that share M18. If M18.3 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
- M18.2Bilateral post-traumatic osteoarthritis of first carpometacarpal joints
- 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 M18.3
- Is M18.3 a billable ICD-10-CM code?
- No. M18.3 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
- Where does M18.3 sit in the tabular list?
- Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Osteoarthritis (M15-M19).