M23 (Internal derangement of knee) compared with S83.61XD (Sprain of the superior tibiofibular joint and ligament, right knee, subsequent encounter), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).
Distinct conditions — both may be reported.
“current injury - see injury of knee and lower leg (S80-S89)”
An Excludes2 note means the excluded condition is not part of the code above it, but a patient can have both. Report both when both are documented.
Source: CMS ICD-10-CM tabular instructional notes
Yes, when both are documented. M23 carries an Excludes2 note covering S83.61XD: “current injury - see injury of knee and lower leg (S80-S89)”
Excludes2 marks distinct conditions — both may be reported when both are documented.
| M23Internal derangement of knee | S83.61XDSprain of the superior tibiofibular joint and ligament, right knee, subsequent encounter | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Internal derangement of knee is a non-billable ICD-10-CM category code (M23). | Sprain of the superior tibiofibular joint and ligament, right knee, subsequent encounter is a billable ICD-10-CM diagnosis code (S83.61D). |
| 7th character | — | The appropriate 7th character is to be added to each code from category S83 |
| Includes | — | avulsion of joint or ligament of knee laceration of cartilage, joint or ligament of knee sprain of cartilage, joint or ligament of knee traumatic hemarthrosis of joint or ligament of knee |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources