皮质外骨桥固定作用的实验研究

Experimental study on the extra-corticul bone bridge fixation

[目的]通过动物实验确定假体与骨交界区植骨能否有效形成皮质外骨桥固定,以及能否起到有效的辅助固定作用。[方法]杂种犬36只,随机均分为4组,右下肢股骨中段切除3cm,插入特制假体替代骨缺损。4组动物分别采用珍珠面假体植骨固定、骨水泥植骨固定、珍珠面假体非植骨及骨水泥固定非植骨固定。4组动物随机于植入后6、12、20周分批处死,标本行组织学、X线摄影研究和生物力学研究。[结果]研究发现植骨区可有效形成紧密骨桥固定,多孔表面植骨组抗扭转应力较骨水泥固定非植骨组高。[结论]假体与宿主骨交界区可有效形成骨桥,此骨桥可有效加强假体的固定。

[ Objective ] To confirm whether an effective extra-cortical bone bridge could be formed around the conjunction between stem shoulder and the bone ends with a combined bone grafting method in canine experimental model. [ Method ] Thirty-six mongrel dogs were divided into 4 groups： pearl surface prosthesis with or without bone graft, and bone cement fixed prosthesis with or without bone graft, and 3 cm femoral defect was made with implantation of simulated prostheses. Specimens of the bone and the embedded implants were retrieved at 6th, 12th, and 20th weeks after operation. Histological, roentgenographical and biomechanical studies were carried out. [ Result] Effective extra-cortical bone bridge was successfully constructed tin the graft area in the experimental animals. There was no gap or soft tissue between the bone bridge and the surface of the prostheses. Biomechanical strength in the grafted groups were significantly better than that of non-grafted groups. [ Conclusion ] The bone bridge could be effectively formed by good grafting technique. Extra-cortical bone bridge fixation is very important for tumor prostheses fixation.