ObjectiveTo review the application and research progress of in vivo bioreactor as vascularization strategies in bone tissue engineering. MethodsThe original articles about in vivo bioreactor that can enhance vascularization of tissue engineered bone were extensively reviewed and analyzed. ResultsThe in vivo bioreactor can be created by periosteum, muscle, muscularis membrane, and fascia flap as well as biomaterials. Using in vivo bioreactor can effectively promote the establishment of a microcirculation in the tissue engineered bones, especially for large bone defects. However, main correlative researches, currently, are focused on animal experiments, more clinical trials will be carried out in the future. ConclusionWith the rapid development of related technologies of bone tissue engineering, the use of in vivo bioreactor will to a large extent solve the bottleneck limitations and has the potential values for clinical application.
The stress distribution and different abduction angles have a close relation to the hip joint. The purpose of this study is to provide biomechanical evidence for the treatment or precaution of hip joint injuries. A three-dimensional model of the hip was established through a series of processing based on the normal human hip joint computed tomograph (CT) image data which were applied to reverse engineering software Mimics14.0 in this study. Firstly, a three-dimensional finite element model was generated with meshing and assigned material and then it was imported into the finite element analysis software Ansys13.0. At last the stress at the femoral neck was solved, computed and analyzed in the positive orthostatic position with 7 hip abduction angles of the hip joint: 0°, 5°, 10°, 15°, 20°, 25°, and 30°, respectively. The results showed that the stresses of femoral neck and outer region were obviously higher than those of front and rear area of the neck of femur in the upright position or abduction of a different angle. With the increase of abduction angle, femoral neck in front of the regional stress value basically unchanged and rear area decreased, but the more obvious changes occurred in the outer region although the stress of inner and outer area also increased gradually. The hip abduction may cause changes in stress distribution because of the femoral neck stress mostly concentrated in the inner and outer cortex, and therefore it has an important role in guiding for hip surgery injury patients to choose the most reasonable solutions and prevention initiatives.