A Novel Technique for Dynamic External Fixation of Proximal Interphalangeal Joint Fracture-Dislocations

Abstract

Background: The pins and rubbers traction system is widely used to treat unstable proximal interphalangeal (PIP) joint fracture-dislocations. However, dealing with rubber bands can be difficult due to its elasticity and weakness. The purpose of this study was to report the results of an alternative dynamic external fixator technique for unstable PIP joint injuries. Methods: Thirteen patients with acute unstable PIP joint fracture-dislocation (n = 8), pilon fracture (n = 2), or comminuted shaft fractures of a middle phalanx with or without PIP joint extension (n = 3) were enrolled. The alternative fixator used a plastic syringe to maintain distraction force instead of the commonly used rubber bands. Four patients underwent combined open reduction due to unsatisfactory reduction by closed mean. The fixator was removed when there was radiographic evidence of healing. Results: At 6 months after the operation, the mean active ROM of the injured PIP joint was 89° (range, 70-104°), and the mean Quick-DASH score was 9.78 (range, 0-40.9). The mean NRS of pain before fixator removal was 1 (range, 0-4). One patient had a pin tract infection and underwent debridement and fixator removal at 33 days postoperatively. There was no loss of reduction or implant failure in the study. Conclusions: The results were comparable to other dynamic external fixation techniques used for unstable PIP joint fracture-dislocations. The main advantages of this technique were strength of the system, procedure simplicity, the compact design, and relatively low cost. In addition, this technique can also be used in pilon fractures and comminuted shaft fractures of a middle phalanx with or without PIP joint extension.

Keywords: Dynamic external fixator; PIP; Pins and rubbers; Proximal interphalangeal joint; Syringe.