Osteoarthritis involves a wearing down of the cartilage within a joint. It can affect any joint in the body, but it most commonly affects joints in the hands, hips, knees, and spine. Over the last few years, a new medicine called hyaluronan has been used for treating osteoarthritis. Hyaluronan is a man-made preparation of a protein complex that occurs naturally in joints and that is often low in people with osteoarthritis. Although hyaluronan has been used in millions of people with knee osteoarthritis, it is not yet FDA approved for use in the thumb. The purpose of this study is to determine the safety and effectiveness of hyaluronan in relieving arthritis symptoms at the base of the thumb and to compare it to corticosteroids and local anesthetic. Specifically, the study will evaluate pain relief, patient satisfaction, and functional outcomes among participants.