Biomechanical characteristics of human trabecular bone

Objective. To evaluate the effect of strain rate (ġ3), apparent density (varrhoa) and tissue density (varrhot) on Youngʹs modulus (E), strength (σu) and ultimate strain (var epsilonu) on intervertebral bone from a Chinese population. Methods. Testing was performed by uniaxial compression at five strain rates on 36 human trabecular bone specimens from three male T12˜L4 vertebrae. Results. Apparent density ranged between 0.46 and 0.71 g/cm3. Tissue density ranged between 1.02 and 1.54 g/cm3. Non-linear regression analyses using strength, Youngʹs modulus or ultimate strain as dependent variables (Y) and strain rate and apparent density or tissue density as independent variables were performed using the following equation: Y = avarrhobġ3c. The exponent of apparent density and strain rate to Youngʹs modulus were 1.88 and 0.07, separately (P = 0.0007). The variation of strength was explained only by apparent density with an exponent of 1.29 (P = 0.0107). The variation of Youngʹs modulus was explained equally by the quadratic and cubic relationship to apparent density or tissue density (P < 0.01). Ultimate strain varied independently of apparent density or tissue density and strain rate.