What Is a Synovial Cyst?

Synovial cysts refer to benign and localized cystic masses attached to the joint capsule, tendon sheath, or synovial sac. The disease can occur at any age, and the most common age is 51 to 60 years. The etiology is unknown and may be related to chronic injury, which can be secondary to other joint diseases. Synovial cysts often occur individually or in multiples on the fingers, sometimes on the distal end of the toes, and on the extended side of the knuckles. The cyst is colorless, clear, or lightly red.