Jornal de Trauma e Tratamento

The Biomechanical Effects of Combining Rigid and Dynamic Fracture Fixation in Simple Fractures

Abstract

Papineau JL, Bauer S, Hayes AJ, Stoffel K, Day RE and Kuster MS

Introduction: Bridge plating has superseded rigid internal fixation in most situations. In simple fractures increased time to union has been reported. This biomechanical study investigates whether the combination of dynamic and rigid fixation allows for adequate interfragmentary movement.

Methods: Standardised fractures were created in bone surrogates and fixed with either a standard bridging plate construct using a locking compression plate or Non Contact Bridging (NCB®) plates using Far Cortical Locking screws (FCLS, MotionLoc™). The constructs were axially loaded to simulate non, touch and partial-weight bearing and interfragmentary motion measured.

Results: The standard bridge plating and the far cortical locking constructs fixed with a “fracture gap” showed significantly increased fracture motion (p<0.005) relative to other groups. No significant difference in fracture motion was demonstrated between any of the 3 groups, where the osteotomy was anatomically reduced, regardless of the presence of an inter-fragmentary screw.

Conclusion: The combination of a lag screw and dynamic plate osteosynthesis allows sufficient fracture motion for secondary bone healing. In simple fracture patterns the addition of a lag screw did not impair fracture motion.