Forty-five flexor carpi radialis (FCR) tendon interposition arthroplas
ties of the trapezium for the treatment of carpometacarpal osteoarthri
tis were reviewed. The average follow-up period was 103 months (range,
22-213 months). Pain was reduced in 42 (93%) of the cases, Mobility w
as equal to that of the unoperated side. Key pinch and grip strengths
compared to the unoperated thumb measured 86% and 90%, respectively. T
he mean distance between the scaphoid and the base of the first metaca
rpal bone was 7 mm (range, 2-12 mm). Function was improved in 39 (87%)
of the cases, and in 42 (93%) of the cases the overall results were s
atisfactory. The results of this study show that FCR tendon interposit
ion arthroplasty gives satisfactory long-term results.