M13.1 – Monoarthritis, not elsewhere classified
ICD-10-CM 2027 diagnosis code · Inflammatory polyarthropathies
ICD-10-CM code
M13.1
- Code
M13.1(claims format:M131)- Description
- Monoarthritis, not elsewhere classified
- 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
- M05-M14 Inflammatory polyarthropathies
- Parent codes
- M13
Billable codes under M13.1
M13.1 is a header code and cannot be used on claims. Choose the most specific code:
- M13.10 – Monoarthritis, not elsewhere classified, unspecified siteBillable
- M13.11 – Monoarthritis, not elsewhere classified, shoulderHeader (more codes below)
- M13.12 – Monoarthritis, not elsewhere classified, elbowHeader (more codes below)
- M13.13 – Monoarthritis, not elsewhere classified, wristHeader (more codes below)
- M13.14 – Monoarthritis, not elsewhere classified, handHeader (more codes below)
- M13.15 – Monoarthritis, not elsewhere classified, hipHeader (more codes below)
- M13.16 – Monoarthritis, not elsewhere classified, kneeHeader (more codes below)
- M13.17 – Monoarthritis, not elsewhere classified, ankle and footHeader (more codes below)
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
M13 – Other arthritis
Related codes in M13
Frequently asked questions
What is ICD-10 code M13.1?
M13.1 is the ICD-10-CM code for monoarthritis, not elsewhere classified, in the block M05-M14 (Inflammatory polyarthropathies).
Is M13.1 a billable code?
No. M13.1 is a header code with more specific child codes; report one of the billable codes listed above.
What category does M13.1 belong to?
It belongs to category M13 – Other arthritis.
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.