Often no treatment is necessary and the practitioner can observe the cyst over time. Arthroscopic surgery to decompress the cyst and treat any meniscal tear may become necessary if the cyst is extremely large or painful. Aspiration, or draining the cyst with a needle, will decrease cyst size but generally the cyst recurs.

A Baker's cyst is a benign lesion that will not cause any long-term harm, but can be annoying and painful. Long-term disability is very rare, as most cases improve with time or arthroscopic surgery.

Complications are unusual but include:

• chronic pain and swelling
• complications from associated injuries, like meniscal tears

Call for an appointment with your health care provider if there is a swelling behind the knee that becomes large or painful. Pain could be a sign of infection, which is not normally associated with Baker's cyst.