M66.8 – Spontaneous rupture of other tendons
ICD-10-CM 2027 diagnosis code · Disorders of synovium and tendon
ICD-10-CM code
M66.8
- Code
M66.8(claims format:M668)- Description
- Spontaneous rupture of other tendons
- Billable
- No – use a more specific code below
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 13. Diseases of the musculoskeletal system and connective tissue (M00-M99)
- Block
- M65-M67 Disorders of synovium and tendon
- Parent codes
- M66
Billable codes under M66.8
M66.8 is a header code and cannot be used on claims. Choose the most specific code:
- M66.80 – Spontaneous rupture of other tendons, unspecified siteBillable
- M66.81 – Spontaneous rupture of other tendons, shoulderHeader (more codes below)
- M66.82 – Spontaneous rupture of other tendons, upper armHeader (more codes below)
- M66.83 – Spontaneous rupture of other tendons, forearmHeader (more codes below)
- M66.84 – Spontaneous rupture of other tendons, handHeader (more codes below)
- M66.85 – Spontaneous rupture of other tendons, thighHeader (more codes below)
- M66.86 – Spontaneous rupture of other tendons, lower legHeader (more codes below)
- M66.87 – Spontaneous rupture of other tendons, ankle and footHeader (more codes below)
- M66.88 – Spontaneous rupture of other tendons, other sitesBillable
- M66.89 – Spontaneous rupture of other tendons, multiple sitesBillable
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
M66 – Spontaneous rupture of synovium and tendon
Includes:
- rupture that occurs when a normal force is applied to tissues that are inferred to have less than normal strength
Excludes2 (not included here):
- rotator cuff syndrome (M75.1-)
- rupture where an abnormal force is applied to normal tissue - see injury of tendon by body region
Related codes in M66
Frequently asked questions
What is ICD-10 code M66.8?
M66.8 is the ICD-10-CM code for spontaneous rupture of other tendons, in the block M65-M67 (Disorders of synovium and tendon).
Is M66.8 a billable code?
No. M66.8 is a header code with more specific child codes; report one of the billable codes listed above.
What category does M66.8 belong to?
It belongs to category M66 – Spontaneous rupture of synovium and tendon.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.