BIOMECHANICAL CHARACTERISTICS OF HUMAN TRABECULAR BONE

Objective. To evaluate the effect of strain rate (epsilon), apparent d ensity (rho(a)) and tissue density (rho(t)) on Young's modulus (E), st rength (sigma(u)) and ultimate strain (epsilon(u)) on intervertebral b one from a Chinese population. Methods. Testing was performed by uniax ial compression at five strain rates on 36 human trabecular bone speci mens from three male T(12)similar to L-4 vertebrae. Results. Apparent density ranged between 0.46 and 0.71 g/cm(3). Tissue density ranged be tween 1.02 and 1.54 g/cm(3). Non-linear regression analyses using stre ngth, Young's modulus or ultimate strain as dependent variables (Y) an d strain rate and apparent density or tissue density as independent va riables were performed using the following equation: Y = a rho(b) epsi lon(c). The exponent of apparent density and strain rare to Young's mo dulus were 1.88 and 0.07, separately (P = 0.0007). The variation of st rength was explained only by apparent density with an exponent of 1.29 (P = 0.0107). The variation of Young's 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 d ensity or tissue density and strain rate. Relevance An understanding o f the biomechanical characteristics of human trabecular bone can help us to understand the mechanism of spine compressive fracture. (C) 1997 Elsevier Science Ltd. All rights reserved.