ABSTRACT
OBJECTIVE: The aim of this study was to to determine the comparative stiffness following repair of an axial sagittal fracture model in equine distal sesamoid bones using either a single 3.5-mm or 4.5-mm cortical bone screw placed in lag fashion. STUDY DESIGN: The present study was an in vitro biomechanical study. RESULTS: The mean (±standard deviation) stiffness value for the 4.5-mm screw-bone construct (522.49 N/mm ± 168.21) was significantly greater than the 3.5-mm screw-bone construct (408.46 N/mm ± 131.13) (p = 0.047). This represents a 28% difference in mean stiffness. CONCLUSIONS: In vitro, the 4.5-mm screw-bone construct creates a stiffer repair of fractured distal sesamoid bones by a margin of 28%. The 4.5-mm cortical bone screw may better withstand forces imparted on the distal sesamoid bone sustained during anaesthetic recovery, normal weight bearing and athletic exercise, thereby minimizing the risk of implant failure.