Anatomic reduction of mallet fractures using extension block and additional intrafocal pinning techniques.

Background: The purpose of this article is to report the efficacy of the extension block pinning and additional intrafocal pinning technique applied to cases whose mallet fractures were not reduced with extension block pinning alone.

Methods: We retrospectively reviewed 14 digits with 14 patients who were treated with the extension block pinning and additional intrafocal pinning technique. There were eight men and six women with an average age of 34 years. The average articular surface involvement was 52%. The average follow-up was 16 months and the mean time from injury to operation was 23 days.

Results: All the cases achieved anatomic reduction of fractures. By Crawford's classification, 9 were excellent and 5 were good. The average active flexion of the distal interphalangeal joint was 78 degrees and the average extension loss was 1.8 degrees. Bone union was observed in all cases after a postoperative mean of 38.4 days. Complications such as skin necrosis, fracture of bony fragments, and nail-plate deformity were not found.

Conclusions: Additional intrafocal pinning technique is considered a simple and useful method to obtain anatomic reduction of mallet fractures in cases where extension block pinning alone is insufficient to restore the anatomic configuration of the articular surface.