Abstract: Objective To develop a bone defect model suitable for loading degradable materials. Method A rat femoral midshaft segmental bone defect model was established. Subcutaneous superficial fascia ( 1 cm×2 cm) was harvested from the surgical site, and a 1. 2 mm-diameter bone traction pin was used to fix the femur. A 4-mm-long segment of half-bone tissue was excised from the midshaft to create the bone defect model. The defect area was wrapped and sutured with the superficial fascia, followed by layered suturing of the muscle and skin. The experiment was divided into three groups: ( 1) the blank control group, which received no fascial wrapping; ( 2) the inactivated fascia group, in which the defect area was wrapped with superficial fascia inactivated by 70% ethanol for 10 min; ( 3 ) the fascia-wrapped group, in which the defect area was wrapped with fresh superficial fascia. Result Compared with the blank control group, both the inactivated fascia group and the fascia-wrapped group showed significantly accelerated bone defect healing. The X-ray scores were significantly higher in the inactivated fascia group and the fascia-wrapped group than in the blank control group (P<0. 05) , and the percentage of healing area was significantly higher than that in the blank control group ( P<0. 01) . The fascia-wrapped group exhibited the best healing effect. Conclusion The improved bone defect model significantly enhances bone defect healing and shortens the healing time, providing a more suitable animal model for loading degradable materials.

Key words: bone defect model, subcutaneous superficial fascia, loadable materials, Micro-computed tomography (Micro-CT)

摘要： 目的 制备一种适用于负载可降解材料的骨缺损模型。 方法 采用大鼠股骨中段截断式骨缺损模型,取手 术部位皮下浅筋膜 1 cm×2 cm,1. 2 mm 直径骨牵引针固定股骨,选股骨中段截取 4 mm 长的一半骨组织制成骨缺损 模型,浅筋膜包被缝合固定于骨缺损区,逐层缝合肌肉及皮层。 实验分为 3 组:空白对照组( 不做包被处理的骨缺 损模型) 、筋膜灭活组(在骨缺损区采用 70%乙醇灭活 10 min 后的皮下浅筋膜包被) 和筋膜包被组(在骨缺损区采 用皮下浅筋膜包被) 。 结果 与空白对照组比较,筋膜灭活组及筋膜包被组骨缺损愈合速度明显加快,X 线评分结 果显著高于空白对照组(P<0. 05) ,愈合面积百分比极显著高于模型对照组( P< 0. 01) ,以筋膜包被组愈合效果最 佳。 结论 采用改进后的骨缺损模型可显著提高骨缺损愈合效果,缩短骨愈合时间,为负载可降解材料提供更适 合的动物模型。

关键词: 骨缺损模型, 皮下浅筋膜, 负载材料, 微型计算机断层扫描技术