Biomechanical testing of a novel osteosynthesis plate for the ulnar coronoid process.

Background: The present study aimed to biomechanically evaluate a novel locking plate intended for osteosynthesis of coronoid fracture compared to mini L-plates and cannulated screws.

Methods: Biomechanical tests were performed on a fracture model in synthetic bones. Three groups, each with eight implant-bone-constructs, were analyzed in quasi-static and dynamic tests. Finally, samples were tested destructively for maximum strength.

Results: The mean (SD) highest stiffness was measured for the novel plate [693 (18) N/mm], followed by the mini L-plate [646 (37) N/mm] and the cannulated screws [249 (113) N/mm]. During the cycling testing of the novel plate and the mini L-plate, no failures occurred, although three of the eight samples of cannulated screws failed during the test. The mean (SD) maximum strength during the destructive testing was 1333 (234) N for the novel plate, 1338 (227) N for the mini-L-plate and 459 (56) N for the cannulated screws. No statistical differences were found during the destructive testing between the two plates (p = 0.999), although statistical differences were found between both plates and the cannulated screws (p = 0.000 each).

Conclusions: Osteosynthesis of the coronoid process using the novel plate is mechanically similar to the mini L-plate. Both plates were superior to osteosynthesis with cannulated screws.