S81Open wound of knee and lower leg

S81 is the ICD-10-CM diagnosis code for open wound of knee and lower leg. It belongs to block S80-S89 (injuries to the knee and lower leg) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is a header code, so it can't be reported by itself; one of its 2 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: S81.0 (knee) and S81.8 (leg).

Don't report S81 together with the conditions in its Excludes1 note: open fracture of knee and lower leg (S82.-) and traumatic amputation of lower leg (S88.-).

The conditions in its Excludes2 note aren't part of S81, but may be coded alongside it if the patient has both: open wound of ankle and foot (S91.-).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.