M23.9
Header — not billableUnspecified internal derangement of knee
The ICD-10 code for unspecified internal derangement of knee is M23.9.
M23.9 is a non-billable header code. It groups related conditions but cannot be used on its own for reimbursement — select one of the 3 more specific codes below.
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •This is a non-billable header code. Documentation must support a more specific child code before this diagnosis can be reported on a claim.
- •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.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
- M23.0Cystic meniscusnon-billable header
- M23.2Derangement of meniscus due to old tear or injurynon-billable header
- M23.3Other meniscus derangementsnon-billable header
- M23.4Loose body in kneenon-billable header
- M23.5Chronic instability of kneenon-billable header
- M23.6Other spontaneous disruption of ligament(s) of kneenon-billable header
- M23.8Other internal derangements of kneenon-billable header
- M23.9Unspecified internal derangement of kneenon-billable header