Preliminary Study Of Natural Horn Materials On Histocompatibility

Objective:The chest wall injury of 20% -40% is combined with rib fracture, severe chest trauma may result in which can lead to soften chest wall, abnormal respiratory movement and mediastinal swing, respiration and circulation will be adversely affected. If the treatment is not timely or not handled properly, multiple rib fractures can easily cause to death of patients. The majority of rib fractures can be cured by conservative treatment, but when a larger area of the chest wall and the chest wall to soften fluctuations, they must take measures to stabilize the chest wall.In recent years with the pathophysiology of flail chest for further in-depth study, surgical fixation for the treatment of multiple rib fractures has been re-valued, and is in-depth study of new fixed equipment and methods. Multiple rib fracture fixation has been more than 50 years, and its significance in clinical practice has been fully affirmed, implant materials are the main fixed materials, which are normally required to meet the following conditions: (l) After implantation in vivo can be maintained long-term tensile strength to stabilize the chest wall. (2) implants can be accepted for the host, long-term deposit no adverse reaction. (3) low density, thinner and susceptible to X-ray penetration, which will be advantageous for reviewing the chest. (4 ) has a stable physical and chemical properties,Through a variety of processing, sterilization does not affect its performance. (5) sources of material sufficient, cheap, and easy to carry. (6) is not teratogenic, carcinogenic. There is no kind of material can content with these requirements.Horn, allogeneic fibrin keratosis as its main ingredients, known as the "bone in vitro",its hardness decreased after prolonged immersion in water, but flexibility is increased, while after sterilization by the high temperature and high pressure, its characters no significant change ,made it for a certain specification strip or plate must have a certain amount of flexibility. Through this experiment we will have a preliminary study for the biocompatibility and mechanical compatibility of natural horn, to explore whether the horn material can be applied to internal fixation of multiple rib fractures, and thus offer its clinical experimental basis for further applications.Methods:Got 72 New Zealand rabbits, of either sex, weight 2.44±0.33kg, were randomly divided into two groups, experimental group and control group, each 36, each further divided into six groups, each group 6, were: experimental group 1, experimental group 2, experiment 3 groups, experiment four groups, experimental group 5, experiment 6 group and the control group 1, control 2 group and the control 3 group and the control group 4, control 5 group and the control group 6 .Cut and trimmed a yellow horn into a plate which thickness 2mm, width 3mm, length 30mm, a total of 36, with spring tension scale to measure the tensile strength, and randomly divided into six groups of six, high temperature and high pressure disinfection alternative. Sheep casing panels are trimmed into the above-mentioned specifications, Bromogeramine immersion disinfection of the reserve.Take the experimental group rabbits, Sumianxin II, intramuscular anesthesia, take the rabbits and fixed on the operating table in prone position, electric razor shaved rabbit hair of both sides, disinfect twice later with Iodophor, Shop Sterile towel, Parallel to the 9th rib on the left to do vertical incision, separation of muscle over ribs, use a small knife along the rib periosteum traveling damage it and set tow silks of 4th along the vertical direction with the ribs,when you mention threads, using scissors cut the ribs, will be pre-prepared The horns affixed to the ribs and face, with No. 4 silk binding is fixed, the muscles and skin sutured layer by layer, the location of the right side of the ribs in the same way symmetrical destruction of periosteum, cut the ribs, but not fixed, the muscles and skin sutured layer by layer, completion of surgery to give intramuscular ceftriaxone 0.1g, withdrawn from circulation to be regained consciousness raising, the group of other rabbits operate the same; to take the experimental group of rabbits, using the same method anesthesia, fixed, disinfection shop alone, the anatomy of the left 9th rib, destruction periosteum, cut the ribs, the sheep casing plate affixed to the ribs and face, with 4th silk fixed anatomical location of the ribs on the right symmetry, the cut, not fixed, patients given intramuscular injection of ceftriaxone completed 0.1g, to be withdrawn from circulation after keeping awake . Experimental observations in rabbits incision without infection, suppuration, buried plant discharge phenomena, in after 3 days, 1 week, 2 weeks, 4 weeks, 8 weeks, 12 weeks were collected from the experimental group and control group within a group home group Rabbit, Executed by the original incision to open after the muscle to observe the horn, and sheep casing panels surrounding tissue inflammation reaction, taking the surrounding tissue and heart, liver, lung, kidney fixed, remove the horn, and whether observed changes in sheep casing plate, and make a measurement of tensile strength of the horn plate, make the surrounding tissues for HE staining and observe the infiltration of inflammatory cells, proliferation of fibrous tissue, fracture healing, and viscera whether the toxicity of change.Results:1. Experimental group and control group in the early stage after implantation, buried plant could be seen around the general organization of inflammatory hyperemia, edema, microscopic observations to neutrophil and eosinophil infiltration in the main, two weeks then gradually turn into a chronic inflammatory reaction, and gradually a large number of tissue cells and fibroblasts, in general the formation of scar tissue can be seen, buried fiber plant can be seen wrapped around the formation, from the perspective of general and pathological inflammatory reactions were observed no significant differences;2. After experiment groups and control groups rabbits were executed, take heart, liver, lung and kidney generally observed no obvious abnormalities, after fixation stained, no significant cell damage and tissue fibrosis, adverse reactions;3. Horn plates were taken out no significant damage, tensile strength measured at the implant significantly decreased in the initial stage, a week later no significant change in tensile strength and toughness, and bending better; the control group sheep casing material, taken out to soften significantly, the anti - pull down than obvious.4. 4,8,12 weeks later ,X-ray examination shows that two groups of rib fractures healed well, and the horn plate has similar density with tissue, almost non-imaging.5. 8,12 weeks later, the experimental group on both sides of the ribs can be seen along the horn plate after remove the horn plate , In the control group only the formation of pure fibers wrapped.Conclusion:1. The horn plates have no obvious rejection and visceral toxicity compared with sheep casing materials, and there are no significant difference about the inflammatory reactions of surrounding tissues, either could form a complete fiber package around the horn plates, the possibility which can be accepted by the body has been preliminarily confirmed.2. There is no obvious decreasing of the horn plates'tensile strength from one week to three months, either its'toughness and flexibility are ideal. There is no damage and erosion on the horn plates though all this experiment, so we could have a preliminary view of its physical and chemical properties and good mechanical stability;3. Through X-ray and general specimen can be seen that rib fractures are healing well, which could confirm that horn plates, sheep casing materials were no influence on fracture healing.4. X-ray examination shows that horn plates have similar density with tissues , X-ray could through it. So if the ribs and chest wall, sternum can be replaced by the horn plates will not affecting the internal organs imaging.5. Along the horn plate we could see the ossification slot, whether the horn plates could induction bone growth also need a further studied.Outlook:This experiment based on the preliminary research which content mechanical compatibility and compatibility of organization and X-ray imaging of natural horn material. Expected to find an organization compatibility and economic materials for ribs fixation of flail chest, large chest wall defect repair, replacement of artificial sternal elevation. Because of this experiment is a preliminary exploratory study, although got some positive results,but still not perfect in many respects, also need further study.