Mini-Blade Plate to Obtain Length Across Lateral Malleolus Fractures: Surgical Technique and Biomechanical Evaluation.

Abstract

Restoration of fibular length is the main determinant in preventing mal-union and early ankle arthritis in lateral malleolus fractures. A 1/3 tubular plate fashioned into a mini-blade plate can be used to distract the distal fragment and achieve length in a controlled fashion over time. The purpose of this study was to describe the surgical technique and perform a biomechanical comparison of the blade plate to a locking plate. A 1/3 tubular plate is fashioned into a 135° blade plate. Blades are seated into the lateral malleolus and a distally directed force is applied on the plate to obtain length.A lateral malleolus fracture was created in 20 cadaveric ankles. The distal fragment was fixed with either a blade plate (BP, n = 10) or a locking plate (LP, n = 10). A distally directed force was applied by an Instron machine and fracture distraction, maximal load and construct stiffness were measured and compared. The average maximal load was 262.06N compared to 255.52N for the BP and LP groups, respectively. The maximal distraction was 3.57mm compared to 4.57mm for the BP and LP groups, respectively. The loading pattern of the blade plate over time differed from that of a locking plate as the blades seat into bone. A 1/3 tubular mini-blade plate demonstrates biomechanical similarities in terms of load and distraction to the more expensive locking plate. We recommend using this technique for fractures with late presentation or with significant shortening. Level V-Mechanism-based reasoning.