1. Department of Orthopedics; The First Hospital of Hebei Medical University; Shijiazhuang 050031 China
2. Department of General Surgery; Zhangbei Hospital; Zhangbei 076450 China
3. Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing 100191 China
4. Department of Civil Engineering-Engineering Mechanics; University of Arizona; Tucson Arizona 85721
5. State Key Laboratory of New Ceramic and Fine Processing; Tsinghua University; Beijing 100084 China