Thumb carpometacarpal arthroplasty in patients under 50

Purpose: The purpose of this study was to evaluate clinical and radiographic outcomes of thumb CMC arthroplasty in patients under the age of 50 at the time of surgery with a minimum of five-year follow up. Methods: This study was a retrospective case series of patients under the age of 50 who underwent thumb carpometacarpal arthroplasty and had at least 5 years of clinical follow-up. The primary outcome was failure of index procedure, defined as reoperation. Demographics, clinical measures (Disabilities of the Arm, Shoulder and Hand (DASH), Visual Analogue Scales (VAS) for pain and satisfaction, range of motion, grip strength) and radiographs were assessed. Results: 84 patients were included in the study. The patients were predominately female and had a median age of 47 (range 34–49). Median follow-up was 7.7 years (range 5–14 years). Twelve patients (14%) had a complication that required reoperation. Post-operative grip strength did not differ between operative and non-operative hands; however, both tip and key pinch were weaker on the operative thumb compared to non-operative (p < 0.05). VAS pain scores were low (median 0, interquartile range 0–1) and satisfaction scores were high (median 10, IQR 9, 10) at final follow-up. A subgroup of patients who underwent hemitrapeziectomy had a higher rate of revision (5 of 17 revised, 29%); excluding this subgroup, the reoperation rate of complete trapeziectomy with tendon interposition was 10% (7 of 67). Conclusions: At median 7.7 year follow-up, carpometacarpal arthroplasty of the thumb in patients under 50 is associated with low pain scores, high patient satisfaction, but may be associated with a higher rate of revision compared to patients who have surgery at an older age. Level of evidence: Level III Retrospective study