Establishment of three-dimensional finite element digital foot model / 中国组织工程研究

BACKGROUND:To overcome the disadvantages of traditional mechanical analysis of specimens, and establish the finite element model of realistic foot, are the important basements for the finite element mechanical analysis on foot. OBJECTIVE:To establish three-dimensional finite element model of foot and lay the foundation for the finite element analysis of normal foot and foot injury. METHODS:A healthy female volunteer was involved in this study and was detected with spiral CT scanning on the feet. The resulting image was used to reconstruct the three-dimensional model by using Mimics software. Then entity model was generated in Geomagic software. Final y three-dimensional finite element model was established based on the digital main structure in Ansys. RESULTS AND CONCLUSION:The established finite element digital model of human foot included al bone, cartilage and ligament, skin and soft tissue. The three-dimensional finite element model of human foot was established based on CT data and using Mimics, Geomagic, Ansys softwares. The established model had similar size and shape with skeletal mode, and can rotate freely in any angle for a variety of measurement, the foot bones can be arbitrarily split or merge, which is suitable for biomechanical analysis.

Clinical application of injectable calcium sulfate with vacuum mixing for grafting bone defects / 中国矫形外科杂志

[Objective]To evaluate the operability and clinical efficacy of injectable calcium sulfate for grafting bone defects.[Method]From June 2004 to August 2005,22 cases with benign bone lesions were treated with curettage and grafting with injectable calcium sulfate bone graft substitute(minimally invasive injectable graft X3,MIIG X3).There were 13 male cases and 9 femal cases.Their average age was 34.6(ranged,4~55).All the 22 cases were followed-up from 23 months to 37 months,average 31.6 months.All cases took radiographic examination regularly after the operation to assess the absorption rate of MIIGX3 and the formation rate of new bone.[Result]This injectable calcium sulfate with vacuum mixing was easy to use,providing complete fill and bony strength instantly when grafting bone defects.According to the raeiographs,MIIGX3 was absorbed almost at the same rate as new bone ingrowth in 8 to 24 weeks.[Conclusion]MIIGX3 is convenient to graft bone defects with fewer complications,capable of absorbing almost at the same rate as replacement of new bone.It's one of the best bone graft substitutes for grafting bone defects induced by benign bone lesions.