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Objective: tarsometatarsal arch an important part of the human body, its complex anatomy. This study was designed three-dimensional reconstruction of the CT data to foot structure finite element model of the quasi-steady-state finite element stress analysis tarsometatarsal. This way to reveal the the tarsometatarsal joint anatomical structure characteristics to explore the theoretical basis foot by the relationship between force and tarsometatarsal joint injury, explain tarsometatarsal joint injury mechanism the biomechanics aspects of finite element simulation. And clinical diagnosis, treatment, and after treatment evaluation will provide some help. Materials and Methods: In this model, a healthy female volunteers, aged 52, height 164cm weight 57kg, spiral CT scan range includes the following sections in the ankle joint and distal tibia approximately 4cm distal fibula about 5cm. Spiral CT scanning parameters: 120kv, 36mA, the spiral thickness of 0.699mm, the bed forward speed 0.707mm / s. Finally obtained tomographic image of a two-dimensional CT scan resolution of 512 × 512 pixels 239. CT scan data in DICOM format into readable and writable disc. DICOM files import MIMICS10.0 software, skinning the original image segmentation, smooth step to generate the three-dimensional model of the foot bones, and input in the form of a point cloud reverse engineering software Geomagic9.0 generated solid model. Generated solid model assembly in IGES format imported into the finite element analysis software Ansys10.0. Skeleton model to simulate three-dimensional 10-node tetrahedral the structure solid elements SOLID92; the ligaments by anatomical data modeling, three-dimensional subject only to the trolley unit LINK10 simulation; cartilage using 3D only by the strut unit LINK10; skin and soft tissue using SHELL93 LINK8 analog. Between the unit of the skin by a pole unit for consolidating a firm. Final of Health the adult foot three-dimensional finite element model of the structure. This model the mechanical loads, plantar heel skin in the full range of constraints, the rest of the plantar skin bind its longitudinal displacement; tibia proximal end load a vertical downward 280N pressure to solve servant come to the normal state effect trying to foot neutral phase. Followed by the same constraints, loading conditions on the dorsum of the foot (arch highest point of the medial cuneiform, intermediate cuneiform, lateral cuneiform dorsal) vertical downward direct violence, 100N, 200N, 300N, 500N, 1000N, solving the get the simulated reality RCC injury stress distribution. Results: A finite element model, including all bones, ligaments, skin and soft tissue, including human foot. 108,855 nodes of a total of 72,934 units, of which skeleton model 21, 68,110 units, 100,266 nodes; cartilage unit 2329, node 3805; the ligament unit 118, node 219; the plantar skin unit 589, node 1796 . Plantar soft tissue unit 1788, node 2769. People get enough neutral phase under normal conditions and analog RCC injury stress distribution of direct violence by the human feet. Finite Element Analysis of the tarsometatarsal one foot under normal physiological conditions, the maximum stress in the second metatarsal plantar front side; With the dorsum of the foot pressure, the tarsometatarsal joint stress with an increasing, and are mainly concentrated in first, second, third metatarsal plantar the front side, and the opposing articular surface of the metatarsal and tarsal bones. Second metatarsal stress, stress concentration is located in the bottom of the second metatarsal base and the second metatarsal plantar side, the maximum stress of 17MPa. Conclusions: 1. Based on CT data to establish a three-dimensional visual model of the full complement of foot bones. 2, including bones, ligaments, skin and soft tissue, including foot three-dimensional finite element model. 3 were in normal and imitated rolling injury case the tarsometatarsal finite element stress analysis, the tarsometatarsal joint stress cloud. As can be seen from the diagram on the second metatarsal in the RCC injury case the maximum stress concentrated at the base and plantar front side. Clinical cases, tarsometatarsal joint injury patients occurred the second metatarsal base fracture, which indirectly confirmed the reliability of the finite element model of the test can tarsometatarsal joint injury etiology must have a theoretical basis.
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