Participation in this study will last 26 weeks. Screening will include a questionnaire and an x-ray of the affected thumb. Eligible participants will then be randomly assigned to one of three treatments: two hyaluronan injections, one corticosteroid injection plus one local anesthetic injection, or two local anesthetic injections. Participants will receive the injections at the base of their thumb, and the first injection will be followed by the second injection a week later. There will be five study visits that will occur at baseline and Weeks 2, 4, 12, and 26. All study visits will include questionnaires, and except for the Week 2 study visit, they will also include an examination and evaluation of the affected thumb. Photographs of the thumb will be taken at baseline. The injections will occur at baseline and Week 2. At Weeks 8 and 20, questionnaires will be mailed to participants for them to complete. Upon completing the study, participants will have the option of receiving continued treatment with another round of hyaluronic injections.