Both trapeziectomy with ligament reconstruction and tendon interposition and trapeziometacarpal arthrodesis are commonly performed procedures for the treatment of trapeziometacarpal osteoarthritis. The purpose of this study was to compare the outcomes of both treatments for symptomatic osteoarthritis of the thumb trapeziometacarpal joint in a randomized trial.Women who were forty years of age or older were randomized either to trapeziectomy with ligament reconstruction and tendon interposition or to arthrodesis with plate and screws. Patients were evaluated preoperatively and at three and twelve months postoperatively with respect to pain, function (Patient-Rated Wrist/Hand Evaluation [PRWHE] and Disabilities of the Arm, Shoulder and Hand [DASH] questionnaires), joint motion, strength, complication rate, and patient satisfaction.Forty-three patients were enrolled. Since we found significantly more moderate and severe complications following arthrodesis compared with trapeziectomy with ligament reconstruction and tendon interposition (71% versus 29%; p = 0.016), the study was prematurely terminated before the sample size necessary to validly compare the two groups was reached. The higher complication rate for arthrodesis led to an increase in revision surgery (two of seventeen patients). Significantly more patients in the ligament reconstruction and tendon interposition group (86%) than in the arthrodesis group (53%) indicated they would consider the same surgery again under the same circumstances (p = 0.025). In both groups, PRWHE and DASH scores significantly improved over time; however, comparison of the groups showed that the results were similar.Women who are forty years or older with trapeziometacarpal osteoarthritis have fewer moderate and severe complications after trapeziectomy with ligament reconstruction and tendon interposition and are more likely to consider the surgery again under the same circumstances than are those who undergo arthrodesis. Twelve months after surgery, the PRWHE and DASH scores were similar in both groups. We do not recommend routine use of arthrodesis with plate and screws in the treatment of women who are forty years or older with stage-II or III trapeziometacarpal osteoarthritis.