Biomechanical Analysis Of Ankle-Foot Complex During Different Strike Paterns Of Jogging

Objective:Foot strike pattern(FSP)is always influence the safety of jogging.Ankle-foot complex bearing the load of ground reaction forces directly.The purpose of this study was to analyze the biomechanical response of the bony structure and soft tissue of ankle foot in different strike patterns.Methods:The kinematics and kinetics of rearfoot strike(RFS)and non-rearfoot strike(NRFS)were measured in eight male runners at a speed of 3m/s±5%.The measured foot strike angle(FSA),ankle angle and ground reaction force(GRF)were used as loading and boundary conditions for further finite element(FE)analysis.Then,a 3D FE model of ankle foot complex was developed based on the CT of one male subject,and validated.The FE model has been used to investigate the bony structure and soft tissue stress during stance phase of different strike patterns in jogging.The Von Mies stress of the bone,contact stress on the articular facet and tension of the plantar fascia were collected and analyzed.Results:The average range of ankle motion is 38.57° at RFS,and 39.7° at NRFS.An earlier and greater inversion is exhibited in NRFS.There are obvious differences in the vertical GRF curves between RFS and NRFS.The peak contact stress of talocrural joint cartilage during NRFS was 7.41 MPa.Both RFS and NRFS,the peak of first and third principal stresses and Von Mises stress has been found at the articular surface between the cuneiform and the scaphoid.The larger Von Mises stress has been found at the fourth and fifth metatarsal during NRFS running.At NRFS,tension of plantar fascia was found larger than it in RFS.Conclusion:The navicular has been subjected to high tensile stress in RFS,and the plantar soft tissue near the heel bears a greater stress.The fourth and fifth metatarsal has been observed a stress concentration in NRFS.And,larger tension applied on plantar fascia and plantar ligaments in NRFS.