Fatigue failure of cortical bone screws.
An experimental study of the fatigue life of cortical bone screws under conditions which stimulated in vivo usage was performed. The two most important factors influencing fatigue life were axial screw tension (the force normal of the plate to bone) and the cyclic shearing load. All screws failed at the root of the thread in the interface between the plate and the bone. A modified screw design effectively resisted fatigue under the described experimental conditions.
D001696:Biomechanical Phenomena; D001863:Bone Screws; D004868:Equipment Failure; D005269:Femur / Q000601:surgery; D006801:Humans; D066298:In Vitro Techniques; D008669:Metallurgy; D013314:Stress, Mechanical