Joint injection is a procedure used in the treatment of inflammatory joint conditions, such as rheumatoid arthritis, psoriatic arthritis, gout, tendinitis, bursitis, Carpal Tunnel Syndrome and occasionally osteoarthritis. A hypodermic needle is injected into the affected joint where it delivers a dose of any one of many anti-inflammatory agents, the most common of which is corticosteroids. The technique may be used to also withdraw excess fluid from the joint.