Is headless screw a valid alternative for the fixation of Chevron olecranon osteotomy? A biomechanical comparison of four fixation methods

Chevron osteotomy is a popular technique for repairing complex distal humerus intraarticular fractures. However, re-fixation presents challenges like hardware prominence and soft tissue damage. Headless cannulated screws are gaining popularity for fixation due to better bone purchase and less irritation. This study aims to compare different fixation strategies with headless screws for chevron osteotomy fixation. This study utilized 32 polyurethane foam ulna specimens for biomechanical testing. The Chevron osteotomy was performed with an oscillating saw for all specimens. Four different techniques were used for re-fixation: modified tension band wire fixation, plate-screw fixation, cannulated screw fixation, and headless cannulated screw fixation. The constructs were mounted to the testing machine, simulating the elbow in 90 degrees of flexion. All specimens were tested under axial traction. Displacements at 350N and 500N and loads at the failure were recorded. At the load of the implant failure, headless cannulated screw fixation revealed higher force values when compared to the other constructs, and modified tension band wire fixation showed lower force values compared to the other three groups (p < 0.001). The headless cannulated screw fixation group showed no significant differences in osteotomy displacements when tested to a 350N load. There were no significant differences in displacements at a 500N load between the four groups (p = 0.275). This study suggests that headless cannulated screw fixation is a viable and effective option for Chevron osteotomies. Headless cannulated screw fixation makes it a promising alternative to traditional fixation methods. This technique may be a more reliable fixation technique during daily activities and moderate elbow motions, indicating that it has the potential to succeed.