CPT® Code 27345

A synovial cyst in the popliteal space, commonly known as a popliteal or Baker's cyst, is a fluid-filled sac that forms in the back of the knee. This condition is characterized by noticeable swelling and a feeling of tightness behind the knee, which may be accompanied by discomfort or pain. The excision of this cyst involves a surgical procedure where an incision is made in the skin at the back of the knee, directly over the location of the cyst. The surgical approach allows for direct access to the popliteal fossa, where the cyst is typically located between the medial head of the gastrocnemius muscle and the semimembranosus tendon. During the procedure, both blunt and sharp dissection techniques are employed to carefully separate the cyst from surrounding tissues and to identify its connection to the joint capsule. Once the cyst is fully visualized, it is excised, and the area where the cyst originated is examined for any defects in the joint capsule. If a defect is found, it is repaired, and in some cases, a synthetic patch may be used to reinforce the joint capsule, ensuring stability and reducing the risk of recurrence.