The data in this prospective registry will be used 1) to define which surgical and nonoperative techniques are most effective at providing pain relief, restoring function, are cost effective, and patients are satisfied with their outcomes; and 2) to design focused clinical questions regarding the optimal treatment of basal joint arthritis of the thumb in future randomized controlled trials. There are no interventions or changes in patient care associated with this study.

Basal joint arthritis of the thumb is a common condition associated with considerable morbidity. Many non-operative and operative treatments have been described but few multi-center prospective evidence based trials comparing standard treatments have been done. This continuing search for consensus of best clinical practices has been reviewed in a thorough meta-analysis of operative treatments for basal joint arthritis. Through the systematic collection of data regarding patient-specific characteristics, treatment interventions, and longitudinal functional outcome measurements the investigators believe patient outcomes and satisfaction can improve through the elucidation of risk factors for disease progression, and the timing and selection of treatment modalities, either conservative or surgical, for any particular patient. The establishment of a multi-center clinical registry will greatly facilitate these goals.

The study hypothesizes that there exist effective non-operative and operative treatments for certain patient populations with basal joint arthritis of the thumb. There also exists a functionally superior, cost effective, and low risk non-operative or minimally invasive operative treatment regime to alleviate pain and slow the progression of disease in those with less advanced disease. Likewise, there is significant functional, health utility, and economic advantage to surgically treating advanced basal joint arthritis with one of the popularized procedures currently in practice.

Inclusion Criteria:

• Patients who have symptomatic basal joint arthritis.
• Patients who are capable of providing informed consent.

Exclusion Criteria:

• Patients younger than 18 years old at the time of enrollment.
• Patients with neuromuscular disease affecting the operated hand, not caused by the CMC operation.
• Patients with known inflammatory arthritic conditions, such as rheumatoid or psoriatic arthritis.
• Patients with a history of or current infection of the basal joint of the affected hand.
• Patients who are demented or are unable to provide informed consent.
• Patients unable to comply with study guidelines.
• Patients who have metacarpophalangeal joint hyperextension are NOT excluded. These patients will be followed and if they receive a capsulodesis or other procedure at the MCPJ at the same time as their basal joint arthroplasty this will be noted in their data records.

The study subject population will consist of patients who are diagnosed with CMC arthritis of the thumb stages I, II, III, or IV. Recruitment of subjects will be the responsibility of the operating surgeon or a member of his clincal staff.