Treatment of unstable distal phalanx fractures by extra-articular DIP pinning: A series of 12 cases

Abstract

Unstable distal phalanx fractures are typically treated by pinning of the distal phalanx or the distal interphalangeal joint (DIP). Complications include unstable fixation, K-wire migration, septic arthritis and osteoarthritis. To limit these complications, we wanted to explore the benefits of using locked extra-articular DIP pinning. The cohort consisted of 12 patients (mean age 36.3 years) who had an extra-articular (6 cases) or intra-articular distal phalanx fracture (6 cases). All patients were treated surgically with a construct consisting of two connected K-wires: one was placed inside the shaft of the distal phalanx and the other was placed perpendicular to the middle phalanx. The K-wires were removed after 1 month. After an average follow-up of 19.9 weeks, pain was 0.4/10 and the QuickDASH score was 7.41/100 on average. The range of motion was, on average, 30.0° less than the contralateral uninjured side for active flexion, 8.8° less for active extension, 32.0° less for passive flexion and 4.1° less for passive extension. The overall hand strength averaged 85.2% of the contralateral one. One secondary displacement occurred but there were no infections. In all, these findings suggest that locked extra-articular DIP pinning is a simple and reproducible surgical treatment for distal phalanx fractures.

Level of evidence: IV.

Keywords: Articulation interphalangienne distale; Brochage; Distal interphalangeal joint; Distal phalanx fracture; Doigt en maillet; Fracture de la phalange distale; Mallet finger; Pinning.