2017 ISAKOS Biennial Congress ePoster #141
Establishment And Validation Of The Three-Dimensional Finite Element Model Of Stage Ii Adult Acquired Flatfoot
Jian Xu, PhD, Shenzhen, Guangdong CHINA
Wei Lu, MD, PhD, Prof., Shenzhen, Guangdong CHINA
Weimin Zhu, MD, Shenzhen, Guangdong CHINA
Kan Ouyang, Shenzhen CHINA
Haifeng Liu, PhD, Shenzhen, Guangdong CHINA
Hao Li, MD, Shenzhen, Guangdong CHINA
Wenzhe Feng, master of medicine, Shenzhen CHINA
Shenzhen second people's hospital, Shenzhen, Guangdong, CHINA
FDA Status Cleared
We established a three-dimensional finite element model of stage II adult acquired flatfoot
A complete anatomical structural three-dimensional finite element model of stage II adult acquired flatfoot was established, and then verified by the kinematics parameters, thus to provide a basic research model for investigating better therapeutic methods of stage II adult acquired flatfoot.
CT data, anteroposterior and lateral X-rays of each volunteer with stage IIa and stage IIb adult acquired flatfoot were collected. A three-dimensional model was reconstructed by Mimics software and then imported into Geomagic software to divide the model’s surfaces. After that, the bones were assembled and the cartilages, tendons, ligaments were established in the Solidwork software. Finally the attributes of ligaments were included by the software of Abaqus. Then a body-weight force was applied to the proximal surface of tibia to simulate the mid-stance phase, the plantar pressure was analyzed. Meanwhile, the talo-1stmetatarsal angle, calcaneal pitch angle and talo-navicular coverage angle were measured on the deformed model. The results obtained were compared with X-rays taken at one-leg standing position so as to verify the efficacy of this model.
The peak plantar pressure of the stage II flatfoot volunteers who have a body weight of 60 kg and 50 kg respectively all lie under the first metatarsal head, the value were respectively 111.5Kpa and 77.9Kpa. The talo-1stmetatarsal angle measured from X-rays and deformed three-dimensional finite element model of stage IIa flatfoot was respectively 8.2°and 8.3° , with the calcaneal pitch angel respectively 14.96° and 14.41° , the talo-navicular coverage angle 10.17° and 11.78° . The measured deviation was within 2° . The talo-1stmetatarsal angle measured from X-rays and deformed three-dimensional finite element model of stage IIb flatfoot was respectively 24.3°and 25.05° , with the calcaneal pitch angel respectively 10.15°and 9.04° , the talo-navicular coverage angle 21.01°and 19.68° .
This research established three-dimensional finite element model for stage IIa and IIb adult acquired flatfoot, which was verified by the kinematic parameters. The model is accurate, reliable, and can be used as a basis of further research.