Twenty-four mallet fractures which involved at least one third% of the articular surface of the distal interphalangeal joint were treated by open reduction and internal fixation using a single double-ended Kirschner wire at a mean of 9 days after injury (range 4-15). At a mean follow-up of 43 (range 12-18) months the active range of motion, pain and the Warren and Norris criteria were evaluated. The mean active range of motion was from - 2 degrees extension (range 0-10 degrees ) to 72 degrees flexion (range 50-90 degrees ). Nineteen patients were pain free and five suffered from mild pain during strenuous work. The Warren and Norris results were successful in 22 and improved in two cases. Radiographs showed, that all the fractures united in a near-anatomic position but with joint narrowing in six digits.