Hemarthrosis, unspecified knee

This code signifies the presence of blood within the joint space of an unspecified knee. Hemarthrosis indicates intra-articular bleeding, which can result from trauma, coagulopathies, or other underlying medical conditions.

Apply this code when documentation confirms hemarthrosis of the knee, but the specific knee (right or left) is not specified. This is often used in emergency department settings or initial evaluations where laterality may not yet be definitively documented.

• Always strive for laterality (right or left knee) if documented to use a more specific code.
• Code any underlying cause of the hemarthrosis (e.g., fracture, anticoagulant use) as an additional diagnosis.
• Do not use if the hemarthrosis is postprocedural; instead, refer to codes in the T81.0- category.