Investigation On The Influence Of Cerclage Steel-wire Tothe Fracture Healing

Pet fractures has occurred by growing number. In these cases, the injury wascomplex and disabling which threaten to the pets’ lives. Cerclage wire fixation hasbecome a pet fracture with internal fixation important adjunct, widely used at theVeterinary Clinic, Bcause the fixed effects of it was perfect, and easy to operate andso on.But after cerclage wire fixation, pet bone injuries have delayed healing orappear atrophic non-Union, there is not a conclusion of the explanation for thisphenomenon now. The experiment purpose:1. Explore the cerclage wire effect ofdelayed fracture healing;2. compare cerclage wire effects on fracture healing indifferent parts;3. Observe the effects of cerclage wire in fracture healing in rabbitmodel and rat model, and effects of cerclage wire fixation mechanism of fracturehealing.Designing the following tests, Establishment of48Fracture of RADIUS inrabbits model only and were randomly divided into the blank Group (A Group), nearthe elbow fracture of wire cerclage in side groups (B Group), wire cerclage infracture near the wrist end Group (C Groups), each set16Only. Groups onpostoperative1W,2W,3W,4W RADIUS DR checks after operation6W,8W,10W,12W radial three-dimensional CT, amount of edge of the broken end, callus, Densityof bone callus, bony callus edge separate scores for fracture healing. In part2,3,4,6weeks to collect groups of samples of bone callus, compared with bone callusformation, callus specimens made of5μm paraffin-embedded tissue sections and HEdyed, under optical microscope observation of fracture callus formation; Caimmunofluorescence staining, observed under laser scanning confocal bone calciumdeposition.Establishment of24radial fractures in rats, were randomly divided into controlgroup (A ’group), wire cerclage in the fracture line near the elbow end group (B’group), wire cerclage in recent wrist fracture line end group (C ’group),8rats per group. Collected callus samples in each group at postoperative the4thd,8thd,12thd,16thd, and compared the formation of callus; Made callus samples into10μm frozentissue sections and immunofluorescence staining for ALP, then observed theexpression of ALP in confocal situation. Analyzed the remaining callus samples byquantitative PCR sequence analysis, and observed the expression of BSP, ALP,collagenaseⅠ, and BMP-2.According to the above experiments, the follow results were obtained.Radiological examination: The DR of postoperative1w~4w showed that thevolume of callus formation in the same period in group B was less than in group Aand C; The results of three-dimensional callus reconstruction after thethree-dimensional CT of the6thw,8thw,10thw,12thw showed the same period ingroup B after a three-dimensional reconstruction of callus, callus formation wassignificantly less than in group A.Histological examination: HE staining showed that postoperative hematoma ingroup B was significantly longer, and chondrocytes was significantly less than ingroup A; Ca Fluorexon immunofluorescence staining showed that callus tissue ingroup B at the same amount of calcium deposition was significantly less than ingroup A; ALP immunofluorescence staining showed that ALP expression of callustissue in the same period in group B was significantly weaker than group A andgroup C.RT-PCR：PCR results showed that, the expression of BSP, ALP, collagenaseⅠ,BMP-2in group A and in group B had a very significant difference, the expression ingroup A was significantly higher than the same period in group B.The results of this study showed that internal fixation of cerclage wire couldsignificantly slow down the healing.