分米波辐射后肌腱愈合的早期生物力学研究

Biomechanical analysis in the early period of flexor tendon healing after decimeter wave therapy

目的探讨分米波辐射后肌腱愈合早期生物力学变化并观察分米波对主动活动运动的影响。方法选用Leghorn鸡56只，随机分为治疗组和对照组，每组28只。取Leghorn鸡左足第Ⅲ、Ⅳ趾为肌腱损伤模型趾。将趾深屈肌腱切断、修复，术后石膏托固定，手术部位暴露。治疗组术后1d～3周局部用分米波辐射治疗，对照组行空白对照。术后1，7，10，14，18，21，28d取材进行生物力学检测，观察2组肌腱最大拉伸断裂强度（Pmax）、肌腱最大延伸率（δmax）、拉断肌腱粘连带功耗（W0）。结果治疗组术后7，10，14，18，21，28d Pmax、δmax、W0均明显优于对照组，差异有统计学意义（P〈0．05）。结论分米波能抑制肌腱外源性愈合、促进内源性愈合，增加肌腱弹性变形能力和坚韧程度，缩短水肿期并减轻疼痛，为早期主动运动提供了必要条件。

Objective To investigate the biomechanical characteristics of flexor profundus tendons repaired after decimeter wave therapy, and to observe the effect of decimeter wave therapy on early active mobilization. Methods A total of 56 Leghorn chickens were randomly divided into a therapy group and a control group with 28 chickens in each. The 3rd and 4th toes of their left feet were employed for the establishment of a tendon injury model. The flexor profundus tendons were cut and repaired. Gypsum support was applied and fixed with an adhesive plaster after the operation. The operated sites on toes Ⅲ and Ⅳwere exposed. The external fixation was removed 3 weeks later and the chickens were left free to move. Decimeter wave therapy （frequency 915 MHz, power 8 Watts） was applied for 10 minutes once daily on the left foot of each chicken in the therapy group from day 1 until 3 weeks after the operation. Sham decimeter wave therapy was applied to chickens in the control group. Four chickens from each group were randomly selected at the 1st, 7th, 10th, 14th, 18th, 21st and 28th days for biomechanical analysis. Biomechanical parameters including tensile strength of rupture （Pmax） , elongation ratio at rupture （δmax） and the tensile adhesion strength of the rupture zone （W0） were observed at each time point. Results At the 7th, 10th, 14th, 18th, 21st and 28th day after the operation, the differences in Pmax, δmax and W0 between the therapy and control groups were statistically significant. The results of the therapy group were better than those of the control group. Conclusions Local decimeter wave therapy after flexor tendon repair can promote intrinsic healing and reduce ex-rinsic healing. The speed and quality of healing are improved. The elasticity and tenacity of the injured tendons are enhanced. Therefore decimeter wave therapy is helpful for early active mobilization training.