Ng Gabriel Y F, Chung Polly Y M
Department of Rehabilitation Sciences, Hong Kong Polytechnic University, Hong Kong (SAR), China.
Photomed Laser Surg. 2012 Mar;30(3):155-9. doi: 10.1089/pho.2011.3095. Epub 2012 Jan 11.
This study investigated the effects of a therapeutic laser, passive stretching, and their combined treatment on the strength of Achilles tendons with overuse pathologies.
Tendinopathy involving overuse is usually treated with exercise and stretching, but there has been no report on the treatment effect of a therapeutic laser combined with passive stretching on managing this condition. Despite the beneficial effect of a therapeutic laser on healing tendons that have had traumatic injury, its effect on degenerative tendons is not known.
Twenty-five mature Sprague-Dawley (SD) rats were used, with 20 subjected to daily bipedal downhill running for 8 weeks, to induce Achilles overuse, and 5 as normal controls. The exercised rats were divided into four groups: 1, laser treatment; 2, passive stretching; 3, combined laser and stretching; and 4, no treatment, running controls. GaAlAs laser with 660 nm wavelength was applied to both Achilles tendons for 50 sec for Groups 1 and 3. Passive stretching of 20 times/10 sec of maximum ankle plantar flexion was applied to Groups 2 and 3. Treatments were applied after each running session for a a total of 56 treatment sessions. On week 9, the tendons were tested for load-relaxation, stiffness, and ultimate strength.
Stiffness was different (p=0.01), difference in ultimate strength was marginally insignificant (p=0.07), and load-relaxation difference was not significant among groups. Post-hoc analyses revealed that the mean stiffness of all the four exercise groups was lower than the normal control, whereas the ultimate strength from the laser and combined laser and stretching was not different from that of the normal control group, but was higher than that of the passive stretching and no treatment groups.
We conclude that a therapeutic laser and combined laser with passive stretching might slow down the decrease in Achilles tendon strength but would not be able to stop the pathological changes of overuse from developing.
本研究调查了治疗性激光、被动拉伸及其联合治疗对患有过度使用性病变的跟腱强度的影响。
涉及过度使用的肌腱病通常采用运动和拉伸进行治疗,但关于治疗性激光联合被动拉伸对这种情况的治疗效果尚无报道。尽管治疗性激光对创伤性损伤的肌腱愈合有有益作用,但其对退行性肌腱的作用尚不清楚。
使用25只成年斯普拉格-道利(SD)大鼠,其中20只每天进行双足下坡跑8周以诱导跟腱过度使用,5只作为正常对照。运动后的大鼠分为四组:1. 激光治疗组;2. 被动拉伸组;3. 激光与拉伸联合治疗组;4. 不治疗跑步对照组。对第1组和第3组的双侧跟腱施加波长为660 nm的GaAlAs激光,照射50 秒。对第2组和第3组施加最大踝关节跖屈20次/10秒的被动拉伸。每次跑步训练后进行治疗,共进行56次治疗。在第9周,测试肌腱的负荷松弛、刚度和极限强度。
各组之间刚度存在差异(p = 0.01),极限强度差异微乎其微(p = 0.07),负荷松弛差异不显著。事后分析显示,所有四个运动组的平均刚度均低于正常对照组,而激光组以及激光与拉伸联合治疗组的极限强度与正常对照组无差异,但高于被动拉伸组和不治疗组。
我们得出结论为,治疗性激光以及激光与被动拉伸联合治疗可能会减缓跟腱强度的下降,但无法阻止过度使用导致的病理变化发展。