Nonunion after trapeziometacarpal arthrodesis: comparison between K-wire and internal fixation

We reviewed 63 trapeziometacarpal arthrodeses (57 patients) performed in our unit between April 2007 and May 2013 for osteoarthritis. K-wires, plates, headless compression screws and memory staples were used for fixation. The average age of patients was 50 (range 20-78) years and there were 36 men and 21 women with a mean follow-up of 36 (range 6-62) months. K-wires were used in 31 cases, staples in 12, plates in five, and screws in 15 joints. The overall non-union rate was 11%, however, when using K-wires for fixation, it was 20%. Union was achieved in all cases when staples or screws were used for fixation. Disabilities of the Arm, Shoulder and Hand scores were higher in cases where non-union occurred compared with those that united (66.7 vs. 21.9). Trapeziometacarpal arthrodesis for osteoarthritis gives good clinical outcome with lower (DASH) scores when union occurs. K-wire fixation led to a 20% non-union rate, and as a result, the senior author no longer uses this method of fixation.