物理疗法促进髌骨-髌腱结合部损伤早期恢复的实验研究

An experimental study of physical therapy in the early healing of a patellar bone and tendon junction

目的探讨低强度脉冲超声刺激(LIPUS)和功能性电刺激(FES)对兔髌骨-髌腱结合部 (BTJ)损伤愈合的影响。方法 18周龄成年雌性新西兰兔63只,建立髌骨部分切除模型,随机分为超声组、复合组和对照组。超声组在术后3 d开始为期6周的LIPUS治疗,复合组在术后1-4周给予LIPUS治疗,在 5-12周给予FES治疗。通过组织学染色观察BTJ纤维软骨移行带的修复,并进行生物力学测试,以评价其疗效。结果 (1)组织学结果显示,超声组和复合组术后6周在截骨界面均有大量新骨生成,BTJ可见大量新生软骨细胞;术后12周纤维软骨带初步形成;术后18周可见具有过渡结构的纤维软骨带。对照组术后6周纤维母细胞增生,无新骨形成;术后18周出现大量新生软骨细胞,但缺乏纤维软骨带的过渡结构。(2)术后 6,12和18周的力学测量结果显示,各组BTJ随时间的推移而逐渐改建,3个时间点超声组、复合组的极限拉应力均明显高于对照组(P<0．05)。结论 LIPUS和FES可使骨、软骨等多种细胞增生,通过促进新骨形成及重建纤维软骨带的过渡结构,从而加快骨-肌腱结合部位的早期恢复。

Objective To investigation the effect of low-intensity pulsed ultrasound and functional electrical stimulation on the healing of a patellar bone-tendon junction （BTJ）. Methods An animal model of partial patellectomy was formed in 63 mature female New Zealand White rabbits （ 18 weeks old） , and the rabbits were then randomly classified into ultrasound, compound and control groups. The ultrasound group was given low-intensity ultrasound therapy for 6 weeks beginning 3 days after the operation, while the compound group received the same treatment from week 1 to week 4 after the operation, and the compound group was given functional electrical stimulation from week 5 to week 12. The plerosis of BTJ in the fibrous cartilage zone was observed, along with biomechanical examination at the end of the test period. Results （ 1 ） In the ultrasound and compound groups, the histological examination revealed abundant new bone formation at the cut bone interface at 6 weeks after the operation. Many new chondrocytes were observed at the BTJ. A fiber cartilage zone formed beginning 12 weeks after the operation. The fibrous cartilage zones had a transition structure at 18 weeks. In the control group, there was fibroblast proliferation but no new bone formation at 6 weeks after the operation, and abundant new cartilage ceils at 18 weeks, but no transition structure was observed in the fibrous cartilage zones. （2） Mechanical testing at three time points after the operation demonstrated that the BTJ was gradually rebuilt in every group with time. The limit tensile stresses in the ultrasound and compound groups were significantly larger than in the control group at all three time points. Conclusion Low-intensity ultrasound and functional electrical stimulation can promote the proliferation of bone and cartilage cells. This can accelerate new bone formation and rebuild a transition structure of fibrous cartilage, and so speed up early healing of bone-tendon junctions.