摘要
目的建立大鼠关节外骨隧道-游离肌腱移植模型，通过对移植肌腱和骨隧道愈合界面的组织学、生物力学和影像学分析，评价其作为早期腱-骨愈合研究模型的有效性。方法将成年雄性Wistar大鼠左侧后肢的趾浅屈肌腱制成自体游离肌腱（移植物），植人同侧胫骨近端直径1．2mm骨隧道内建立关节外骨隧道-游离肌腱移植模型。分别于术后l、2、4、6周（n=4）处死取材，组织学观察腱-界面组织形态学演变过程；于术后第2、6周（n=6）进行生物力学测试，测定移植肌腱最大抗拔出应力并记录其衰竭模式，对完成生物力学测试的胫骨标本同时进行高分辨率x线成像，观察骨隧道的影像学改变。结果组织学检查显示腱-骨界面早期由一层不定形的疏松纤维肉芽组织构成，随后腱-骨界面组织厚度逐渐减小，周围的新生骨组织逐渐长人并替代肉芽组织；术后6周，腱-骨界面基本消失，移植肌腱与周围骨组织之间可见大量锚固纤维形成。术后6周肌腱平均最大抗拔出应力隧道长度比为（1．00±0．30）N／mm，明显高于术后2周组（0．35±0．17）N／mm；衰减模式在术后2周以肌腱拔出为主，而术后6周以肌腱实质性断裂为主。高分辨率x线成像显示术后2周骨隧道与周围骨间隙清晰，而术后6周骨隧道密度与周围骨相当，间隙变得模糊不清，隧道周围可见小梁骨的改建。结论大鼠关节外骨隧道内游离肌腱的愈合模式在早期与关节内十字韧带重建模型类似，具有手术操作简单、适合双侧肢体同时造模且造模术后对关节活动影响小等优点，是研究早期腱-骨愈合的良好模型。
Objective To establish a novel rat tendon-to-bone healing model with a free tendon graft implanted into an extra-articular bone tunnel and to evaluate the effectiveness of this model for early tendon-to-bone healing process by histologic, biomechanical and radiological analysis. Methods Museulus flexor digitorum superficialis harvested from the left hind legs of 28 male Wistar rats were prepared as free autografts. Each autograft was implanted into a bone tunnel of 1.2 mm diameter created at ipsilateral proximal tibia1 metaphysis. The healing process of the tendon-to-bone interface tissuewas analyzed at week 1, 2, 4and 6 （n=4） after the transplantation. Biomeehanical test including maximum anti-pullout strength and failure mode were evaluated at week 2 and 6 （n=6） after transplantation. Immediately after the biomeehanical test, the samples were also taken by the high-resolu- tion radiography to observe the bone remodeling around the tunnel. Results At week 1, the interface between tendon graft and bone was primarily composed of a layer of amorphous fibrous granulation tissue. The thickness of the interface tissue decreased with the passage of time. This thinning tissue was gradually replaced by the newly formed bone tissue around the tunnel. The inter-face tissue almost disappeared at week 6 with a bunch of anchor fibers connecting the tendon with bone. The failure load-to-tunnel length ratio was significantly higher at week 6 [（1.00±0.30） N/mm] than that at week 2 [（0.35±0.17） N/mm]. The specimens of the tendon-to-bone complex failed by pull-out of the tendon from the bone tunnel at week 2, which translated into a break of the tendon at week 6. High-resolution X-ray imaging shows a clear gap around the bone tunnel at week 2. At week 6, the interface gap became blurred and the bone density at the tunnel site was similar to the surrounding bone tissue. Conclusion The healing pro-cess of a free tendon grant in an extra-articular bone tunnel is similar to that of the intra-articular anterior cruciate ligament recon-struction model. With simple surgical procedure and minimal influence to the postoperative activity, this tendon-to-bone healing model is of particular significance for early studies of tendon-to-bone healing process.
出处
《中华骨科杂志》
CAS
CSCD
北大核心
2014年第8期864-871,共8页
Chinese Journal of Orthopaedics
关键词
前交叉韧带重建
模型
动物
大鼠
Anterior cruciate ligament reconstruction
Models, animal
Rats
