Bone marrow was assumed to be negligible on the aspect of bone mechanical behavior, where bone mass and bone mineral density were most studied. As a result, if the bone marrow, especially the marrow fat, plays a role in the bone mechanical properties is unknown yet. Marrow fat content was found increased in osteoporotic bone. However, the relationship between such change of bone marrow and bone strength is not clear yet. This study was proposed to investigate the effect of marrow fat on the bone biomechanical performance by computer simulations. A finite element model was established based on trabecular structure extracted from quantitative CT at L3 vertebrae. Simulations were conducted on the models with and without marrow fat under the same condition, respectively. The results showed that the cancellous bone with marrow fat had a 7.56%~18.81% higher maximum stress in trabeculae. Further, trabeculae with higher Young's modulus tend to sustain a higher maximum compressive stress when considering the marrow fat. As a conclusion, the marrow fat has effect on bone biomechanics, which cannot be ignored. Such effect in osteoporosis should be further investigated in deep.

Bone marrow was assumed with little effect on the bone mechanical property. As a result, there is no simulation model of bone strength considering bone marrow. While, it has been reported that fat marrow content increased in osteoporotic bone. Whether the fat marrow influences the bone mechanical property is unknown yet. Therefore, the objective of this study was to figure out the contribution of bone marrow fat in bone strength. A finite element model was established by using quantitative computed tomographic (QCT) data from a 63-yearold female's L3 vertebrae. With mechanical load applied on the finite element model, a significant higher maximum stress was observed in the model without bone marrow, compared to the one with fat marrow. The results indicated that bone marrow fat diminish the maximum stress on the trabecular bone and may function as a force buffer in a bone.

No abstract