犬全髋关节置换模型的构建

Construction of a canine model of total hip arthroplasty

背景:在众多全髋关节置换动物模型中,犬因其与人类的高度相似性及易于管理、饲养的特点而倍受青睐。目的:在德国牧羊犬上建立并评价金属对金属全髋关节置换模型。方法:德国牧羊犬随机分为空白对照组,骨水泥固定组,生物固定组。空白对照组仅行手术入路操作,后两组分别行骨水泥固定与生物固定全髋关节置换。分别于术后即刻、3,6,12个月X射线观察植入物形态。结果与结论:空白对照组动物术后恢复好。骨水泥固定组中2只动物发生股骨骨折,继发伤口感染;2只动物置换后假体周围感染;1只动物骨水泥由臼底渗入盆腔。生物固定组中3只动物发生伤口及假体周围感染;1只术后反复发生脱位。其余实验组动物术后恢复好,步态基本正常,术后即刻、3,6,9及12个月X射线片示假体位置良好。实验组手术并发症发生率9%(2/22),总感染率32%(7/22)。说明犬全髋关节置换模型是一个稳定的,成功率较高,可重复的动物模型。

BACKGROUND： Total hip arthroplasty （THA） has become the major treatment of late stage of hip disease. Among lots of THA animal models, the canine is popular because of its similarity to human and being easy to manage. OBJECTIVE： To build up an animal model of metal-on-metal THA based on German Shepherd dogs. METHODS： 33 German Shepherd dogs were divided into four groups： pilot group （n=7）, blank control （n=4）, cemented group （n=11） and cementless group （n=11）. The blank control group only received the approach and suture, while the two experimental groups received cemented and cementless THA. The prosthesis was designed for this project. Animals of these three groups were sacrificed 1 year after surgery, and X-ray films of the hip were taken at the time of 3 months, 6 months and 1 year after surgery for observation of hip morphology. RESULTS AND CONCLUSION： Animals of the blank control group recovered well. In the cemented group, femoral fracture and secondary wound infection occurred in two animals, infection surrounding the prosthesis occurred in two animals, and herniation of cement into the pelvis occurred in one animal. In the cementless group, wound and deep infection occurred in three animals, and repetitive dislocation of the hip joint occurred in one animal. All infected animals were scarified unless the infection was controlled after 1 week of cefuroxime administration. All the other animals recovered well, the gait was nearly normal, and the X-ray films taken immediately, 3, 6, 9 and 12 months after surgery showed that the implants were in a good position. The total complication rate in the arthroplasty operation was 9% （2/22）, and the total infection rate was 32% （7/22）. These findings suggest that the canine model of THA is a stable, repetitive animal model with high successful rate.