Biomechanical comparison of radiopalmar double plating with conventional palmar plating in comminuted distal radius fractures

Abstract Purpose The aim of this study is to analyse the effect of an additional radial buttress plate for palmar plate osteosynthesis in an AO/OTA 2R3 C2.1 fracture model.Methods Nine pairs of fresh-frozen radii were examined for pathology and bone density and assigned pairwise to 2 groups. Palmar fixation was performed with a variable-angle palmar locking plate in one of the groups and supplemented with a radial buttress plate in the other. An AO/OTA 2R3 C2.1 fracture was created. Biomechanical testing was conducted using an established protocol including. Stiffness, range of motion, and individual fragment movements and rotations were evaluated.Results No implant failure was observed. Among all specimens, stiffness increased (p < 0.01) and overall range of motion decreased (p = 0.02). The mobility of the ulnar fragment to the shaft during cyclic testing was smaller with double plating, initially and finally (p ≤ 0.01). Fragment movements increased in the course of testing and were significant for the radial movement among all specimens (p < 0.01). The initial rotation of the ulnar fragment and the final rotation of the radial fragment in relation to the shaft were lower with double plating (p ≤ = 0.05). There was an increase in rotation of the ulnar fragment to the shaft of all radii during cyclic testing (p = 0.048) and the rotation of the ulnar fragment to the shaft was lower than that of the radial fragment (p < 0.02).Conclusion Biomechanically, the radial buttress plate in addition to a common palmar locking plate demonstrated an advantage in the fixation of comminuted distal radius fractures.