Intermittent hydrarthrosis, left knee

This code describes a condition characterized by recurrent, self-limiting effusions (swelling due to fluid accumulation) in the left knee joint. These episodes typically resolve spontaneously but may recur at irregular intervals, often without a clear precipitating factor.

Use this code when documentation specifies intermittent hydrarthrosis affecting the left knee. This diagnosis is supported by a history of episodic knee swelling, physical examination findings of effusion, and exclusion of other causes of joint swelling such as infection, trauma, or inflammatory arthropathies.

• Ensure documentation clearly specifies "intermittent" and the laterality "left knee."
• Do not confuse with chronic hydrarthrosis or hydrarthrosis due to a specific underlying condition (e.g., osteoarthritis, gout), which would require different codes.
• Code any associated underlying systemic conditions or injuries separately, if documented.