[Biomechanical research on upper femur with vertical and bending stress]

To study the bone state with ultimate stress by examining biomechanical distribution of upper femur in Chinese, in order to accumulate more experiences for clinical work.

Totally 60 Chinese femurs from fresh cadavers were randomly divided into two groups. All the femurs were cleaned, and the body age ranged from 36 to 72 years old, averaged 56.4 years, including 41 from males, and 19 from females. These two groups underwent mechanical stress and bending stress tests. Special mechanical laboratory and machines were used to get the information. Results about the loading value at each testing point under stress were collected.

The four faces of the upper femur suffered different stress under external forces. The bone on upper femur can tolerate more mechanical stress than bending stress. Medial and lateral region of the femur neck and the rear side of the small tuberosity section were themain position enduring the vertical stress. The rear position of the base femur neck and the small tuberosity section were the main regions enduring the bending stress. Those main positions had strong cancellous bones. The intertrochanteric fracture fixation and artificial femoral stems were designed depending on this biomechanical basis.

According to our experiment result, doctors need to chose more effective fixations for upper femur fracture, and femoral stems for the patients. More information should be collected by further researches.