CPT® Code 29870

A diagnostic arthroscopy of the knee, identified by CPT® Code 29870, is a minimally invasive surgical procedure that allows for the examination of the knee joint. This procedure can be performed with or without a synovial biopsy, which involves taking a sample of the synovial tissue for further analysis. During the procedure, two small incisions, referred to as portal incisions, are made—one on the medial (inner) side and one on the lateral (outer) side of the knee joint. An arthroscope, which is a specialized instrument equipped with a camera, is inserted through one of these incisions, providing a visual representation of the internal structures of the knee on a video screen. The other incision is used to insert an irrigation cannula, which allows for the flushing of the knee joint with saline solution. This flushing process helps to clear any cloudy fluid or debris, enhancing the visibility of the joint's interior. The surgeon carefully examines the knee joint for signs of injury, disease, or other abnormalities. If necessary, synovial tissue samples are collected during the procedure and sent to a laboratory for further evaluation. Once the examination is complete, the knee is flushed again with saline, the instruments are withdrawn, and the portal incisions are closed, completing the diagnostic process.