Synovial cyst of popliteal space [Baker], left knee

This code signifies a fluid-filled sac, often a distended bursa, located behind the left knee joint. This condition, commonly known as a Baker's cyst, results from the accumulation of synovial fluid that has extruded from the joint capsule into the popliteal space. It typically presents as a palpable mass and can cause pain or stiffness.

Apply this code when documentation confirms a diagnosis of a synovial cyst specifically located in the popliteal fossa of the left knee. This diagnosis is often made clinically through physical examination and confirmed with imaging studies such as ultrasound or MRI. Ensure the laterality (left knee) is clearly documented.

• Confirm the laterality; separate codes exist for the right knee and unspecified knee.
• Distinguish from other knee pathologies like meniscal cysts or ganglion cysts, which have different code assignments.
• Consider an additional code for any underlying knee pathology (e.g., osteoarthritis) if documented as the cause of the cyst.