Design Of Human Metatarsal Fatigue Fracture Model And Biomechanics Analysis In Vitro

Objective To establish the human metatarsal fatigue fracture model and study the fracture biomechanical mechanism in vitro, and provide the reliable correlative theoretical basis for clinical preventting and treading efficaciously. Methods Twelve fresh adult cadaveric feet were selected for experimental fatigue testing to establishing experimental metatarsal fatigue fracture model, specimens were removed soft tissue and the first toes and diaphysises of the first metatarsal bone, reserved ligaments articular capsules , the first tarsometatarsal joints, steel wire substituted the plantar aponeurosis. Buried and clamped the specimen to the MTS Fatigue Tester, the specimen was loaded cyclically at IHz in 350N, and noting the number of cycles to failure. Results Failure occurred in four specimens at 29,285 24798 17956, 31268 cycles partially and showed spiral fracture of the metaphysis the second metatarsal. The others were unsuccessful. Conclusion Fatigue fracture is broken in the bone applied to overload with the repetitive forces. Fatigue fracture of the second metatarsal occurred when it is taken up most of the weight of the body and exposed to stress concentration if the foot is flattening or at the excess plantar flexion. Biomechanical factors, involving anatomical variation, have an important role in the development of fatigue fracture. This fatigue fracturel model is fit for biomechanical study of metatarsal fatigue fracture,...