[Objective]To explore a new technique of prefabricating internal plate.[Method]Three-dimensional reconstruction of the well-liking shinbone was performed by MSCT scanning and the length and shape of the catagmatic shinbone for operation was measured on well-liking shinbone.The shinbone curve was depicted using a self-designed skeletal curve-depicting.Then shape of the material for internal fixation was determined.[Result]The length and shape of the shinbone curve was accurately measured.The physiological curve of the shinbone was depicted.Then shape of the material for internal fixation was determined.[Conclusion]Three-dimensional well-liking shinbone reconstruction with MSCT and measurement facilitates the determination of the optimal length and shape of the internal fixation material to enhance the attachment between the material and the bone surface and consequently the therapeutic effects.One case's length and shape of internal fixation was dissatisfactory for hyperplasia of bone.But the length and shape of internal fixation has basal shape.

The process of tissue repair involves a complex tissue response to injury in which growth factors, playing a major role in this process, trigger, control and terminate soakage of inflammatory cells, cells proliferation, secretion of matrix and scars formation by autocrine, paracrine or both. Thus, growth factors can be used to alter the microenvironment of the wounded tissues and to promote their repair. But, there are notable disadvantages in using purified recombination growth factors, 1) the source is so limited that their prices are expensive; 2) the ir half-lives are short and easy to be destroyed by wound proteases; 3) there is no perfect carrier; 4) high initial doses are required but easy to bring toxicity; 5) it is difficult to apply growth factors in deep wounded tissues again and again, their function cannot be played enough accordingly; 6) most of growth factors are the products of recombination. All above-mentioned disadvantages result in a low activity.

To investigate the influence of high molecular weight polyethylene (HMWP) on the viability of osteoblasts and new bone formation in the process of fracture healing, the osteoblasts derived from adult human bone marrow were cultured in HMWP maceration extract and normal culture medium. The viability of the osteoblasts was measured by MTT assay, and the function of the osteoblasts was detected by use of alkaline phosphatase test kit. The locked double-plating (steel plate and HMWP plate) was implanted and fixed at the artificial fracture of distal femur of dogs. Specimens were gained at 3, 6, 9 and 12 weeks postoperatively, examined with macroscopy, microscope and scanning electron microscope (SEM). The results showed that HMWP did no harm to osteoblasts. There is no significant difference in activities of proliferation and alkaline phosphatase between HMWP maceration extract and normal culture medium at each observation time of at 2,4,8, and 14 dyas (P>0. 05). Bone tissue under the implanted HMWP plate manifested no absorption; the new bones formed under the HMWP plate and gradually matured as time went on. It is demonstrated in this study that HMWP has no adverse influence on the viability of osteoblasts and new bone formation and it can be used as internal fixation implant in treating fractures.
Animals ; Biocompatible Materials ; chemistry ; pharmacology ; Cells, Cultured ; Dogs ; Female ; Femoral Fractures ; surgery ; Fracture Fixation, Internal ; Fracture Healing ; physiology ; Humans ; Implants, Experimental ; Internal Fixators ; Male ; Osteoblasts ; cytology ; drug effects ; Osteogenesis ; drug effects ; Polyethylene ; chemistry ; pharmacology