M13.169
Billable codeMonoarthritis, not elsewhere classified, unspecified knee
The ICD-10 code for monoarthritis, not elsewhere classified, unspecified knee is M13.169.
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •This code describes an unspecified presentation. If the medical record documents a more specific detail (e.g. laterality, type, or affected site), a more specific sibling code should be used instead — see Related codes below.
- •Laterality-specific codes exist for this condition — confirm the affected side is documented.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
- M13.161Monoarthritis, not elsewhere classified, right knee
- M13.162Monoarthritis, not elsewhere classified, left knee
- M13.169Monoarthritis, not elsewhere classified, unspecified knee
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 71666Approximate match
Associated MS-DRGs
M13.169 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.