Arthroscopy is an outpatient surgical procedure used to treat a variety of problems in the joints of the body. Arthroscopy involves the use of a pencil-sized instrument, called an arthroscope, inserted into the joint through a small incision in the skin. The arthroscope contains a camara, a lens, and a light, all miniaturized to fit inside the joint. Arthroscopy was initially used on the larger joints of the body such as the knee, but has now been improved and miniaturized so that it can be used on a variety of other joints, including the wrist.