Outcomes of dual mobility arthroplasty in thumb basal joint arthritis: a clinical and radiographic study of one hundred and fifty prostheses with four-years follow-up

This study evaluated the outcomes of double mobility trapeziometacarpal prostheses for treating osteoarthritis (OA) of the trapeziometacarpal (TMC) joint. A prospective observational analysis was conducted on 150 implants with a maximum follow-up of four years, including a clinical and radiographic assessment and an evaluation of complications. The results indicate a prosthesis survival rate of 97.9% after the first two years post-surgery, calculated using the Kaplan-Meier method. Significant improvements were observed in pain reduction (mean VAS at 3 months post-surgery 2,9 and 1.5 after 6 months), hand grip strength (25.93 kg at 6 months post-surgery), and range of motion (Kapandji score from 8.8 to 9.2, comparing the preoperative mean with the mean after the first postoperative month). The complication rate was low, with only two cases of cup migration and one case of trapezium resorption. Patient satisfaction was high due to the rapid functional recovery and reduced invasiveness compared to traditional techniques. Double-mobility prostheses offer a highly effective treatment for stage II and III TMC OA according to the Eaton-Littler classification, with minimal need for revision surgeries.