M66
M66 — Spontaneous rupture of synovium and tendon
Non-billable headerICD-10-CM
M66 is a non-billable header ICD-10-CM code for spontaneous rupture of synovium and tendon. It cannot be billed on its own: choose one of the more specific child codes below.
Excludes2 — not included here, but may coexist
The excluded condition is not part of this code, but a patient can have both. You may code both.
- rotator cuff syndrome (M75.1-)
- rupture where an abnormal force is applied to normal tissue - see injury of tendon by body region
Includes
Conditions this code covers.
- rupture that occurs when a normal force is applied to tissues that are inferred to have less than normal strength
Other codes that can never be billed with M66
These codes carry an Excludes1 note pointing at M66. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading M66 alone.
Risk adjustment
M66 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 M66
6 child codes. Green means billable.
Questions about M66
- Is M66 a billable ICD-10-CM code?
- No. M66 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
- Where does M66 sit in the tabular list?
- Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Disorders of synovium and tendon (M65-M67).