The effects of therapeutic ultrasound on tendon healing. A biomechanical study

The effect of 1 MHz therapeutic ultrasound on the healing strength of tendons was studied in the tenotomized, repaired and immobilized right Achilles tendons of 26 rabbits. Twelve tendons were sonicated daily in continuous waves at a spatial averaged intensity of 1 W cm(2) [corrected] for 5 min. After nine consecutive treatments, the tendons were excised under anesthesia and compared biomechanically. Exposure to ultrasound induced a significant increase in both the tensile strength and the energy absorption capacity of the tendons. Although healing in rabbits may not translate directly to healing in humans, these findings suggest that surgically repaired human Achilles tendons may heal faster if ultrasound is applied during the early stages of healing.     

Effects of different therapeutic ultrasound intensities on fracture healing in rats

Low-intensity pulsed ultrasound (LIPUS) with I_SATA= 30 mW/cm² has been proven in facilitating fracture healing, which the spatial average intensity over the on period (I_SATP) equals 150 mW/cm². As active ultrasound wave is only delivered during the on period, we postulate 150 mW/cm² is responsible for the beneficial effect of LIPUS. In this study, we compare the biologic effects of 30 mW/cm² and 150 mW/cm². We propose I_SATA = 150 mW/cm² could further enhance fracture healing process. Closed femoral fractured Sprague-Dawley rats were randomized into control, LIPUS-30 (30 mW/cm²) and LIPUS-150 (150 mW/cm²) groups. Weekly radiographs and endpoint microCT, histomorphometry, and biomechanical tests were performed. The results show that LIPUS-30 had significantly higher low-density bone volume fraction and woven bone percentage than that of control and LIPUS-150 in microCT and histologic measurements, respectively. Mechanically, failure torque of LIPUS-30 was significantly higher than control and LIPUS-150 at week 6. In conclusion, LIPUS at I_SATA= 150 mW/cm² did not further enhance fracture healing.     

Comparison of the effects of laser and ultrasound treatments on experimental wound healing in rats

A randomized controlled study investigated the effects of ultrasound and laser treatments on wound healing in rats. The duration of the inflammatory phase decreased with both laser and ultrasound treatments; however, laser was more effective than ultrasound, with more significant results. The proliferation phase showed, for both treatments, an increase in the level of hydroxyproline and the number of fibroblasts, as well as stimulation of the collagen synthesis and the composition. Laser treatment was again more effective than ultrasound. The wound breaking strength was significantly higher with both treatments, and no statistically significant difference emerged between the laser and ultrasound groups, although laser treatment provided a much greater increase in the wound breaking strength than ultrasound. Both treatments have beneficial effects on the inflammatory, proliferation, and maturation phases of wound healing. Both can be used successfully for decubitis ulcers and chronic wounds, in conjunction with conventional therapies such as debridement and daily wound caring. However, laser treatment was more effective than ultrasound in the first two phases of wound healing.     

Therapeutic ultrasound improves strength of achilles tendon repair in rats

The purpose of this study was to evaluate the effects of therapeutic ultrasound on structural properties and functional performance of Achilles tendon healing. Thirty Sprague-Dawley rats with surgical hemitransected Achilles tendon were studied. Ten were treated daily with 1 MHz continuous ultrasound at 1.0 W/cm2 for 4 min, 11 at 2.0 W/cm2 for 4 min and nine served as control without treatment. Achilles functional index (AFI) was recorded preoperatively and on postoperative days 3, 10 and 30. On day 30, the rats were sacrificed and Achilles tendons were tested for load-relaxation, stiffness and ultimate tensile strength (UTS). Results showed that UTS of both low-dose (p=0.023) and high-dose (p=0.002) groups was significantly greater than in controls. No significant differences in AFI (p=0.179), load-relaxation (p=0.205) and stiffness (p=0.842) were found among groups. These findings suggested that both low- and high-dose therapeutic ultrasound accelerate the healing process of ruptured tendon.     

Neuromuscular activation in conventional therapeutic exercises and heavy resistance exercises: implications for rehabilitation

BACKGROUND AND PURPOSE: Central activation failure and muscular atrophy are common after knee joint injury. Thus, exercises that aim to stimulate muscular hypertrophy and increase neural drive to the muscle fibers should be used during rehabilitation. This study examined the level of knee joint neuromuscular activation during 4 conventional therapeutic exercises (quadriceps femoris muscle setting, manual lateralization of the patella, rhythmic stabilization, and the pelvic bridging exercise) and 4 heavy resistance exercises (free-weight squat with a barbell, horizontal seated leg press, isolated knee extension with a cam mechanism, and isolated hamstring muscle curl) in young, untrained men who were healthy. SUBJECTS: Thirteen male subjects (mean age=25.3 years, SD=3.0) with no previous history of knee injury participated in the study. METHODS: Neuromuscular activation during the exercises was defined as the root-mean-square (RMS) electromyographic (EMG) signal normalized to the peak RMS EMG signal of a maximal isometric muscle contraction. RESULTS: Low levels of neuromuscular activation were found during all conventional exercises (<35%). A limitation may be that only a few of many different conventional exercises were investigated. The highest level of neuromuscular activation (67%-79%) was observed during the open kinetic chain resistance exercises (isolated knee extension and hamstring muscle curl). None of the conventional exercises or heavy resistance exercises were found to preferentially activate the vastus medialis muscle over the vastus lateralis muscle. DISCUSSION AND CONCLUSION: The results indicate that heavy resistance exercises should be included in rehabilitation programs to induce sufficient levels of neuromuscular activation to stimulate muscle growth and strength.     

一氧化氮与肌腱愈合☆

背景：研究表明一氧化氮在肌腱损伤愈合中发挥了重要作用。目的：综述一氧化氮与肌腱损伤愈合的相关研究进展。方法：应用计算机检索1992年1月至2011年12月PubMed数据库相关文章,检索词为＂NO,tendon,healing＂,并限定文章语言种类为English。同时计算机检索1995-01/2011-12中国期刊全文数据库相关文章,检索词为＂一氧化氮,肌腱,愈合＂,并限定文章语言种类为中文。共检索到文献115篇,最终纳入符合标准的文献37篇。结果与结论：通常健康肌腱中不表达一氧化氮合酶,而损伤后一氧化氮合酶3种同功酶呈现高表达但表达时相不同,使用一氧化氮抑制剂会削弱肌腱的愈合,而适宜剂量的一氧化氮供体可促进肌腱愈合,其原因之一可能是一氧化氮降低了炎症反应并改善了细胞外基质代谢,从而减轻愈合期肌腱的症状和质量,提高了肌腱的功能。     

PEMF刺激对肌腱内源愈合作用的实验研究

目的研究脉冲电磁场(PEMF)刺激对肌腱内、外源性愈合的作用。方法对32只雌性Wistar大白鼠,制造肌腱内、外源性愈合模型,手术后采用PEMF刺激,通过组织学和6300黄金系统高效氨基酸分析仪(BeckmanUSA)分析研究其作用。结果PEMF对肌腱内、外源愈合均有促进作用;其中肌腱内源性愈合模型的对照组肌腱呈现出中心性变性、坏死的表现;而PEMF组中心变性、坏死程度轻。结论PEMF刺激主要通过促进肌腱内源性愈合而发挥作用。     

超声破坏微泡对大鼠皮肤创面愈合影响的实验研究

目的 探讨超声破坏微泡(声诺维)对大鼠皮肤创面愈合的影响.方法 96只SD大鼠建立皮肤创面模型后随机分成4组:超声破坏微泡组、单纯微泡组、单纯超声组和对照组.超声破坏微泡组经鼠尾静脉注射微泡造影剂0.5 ml,同时用声强度1 MHz、2.0 W/cm2超声辐照3 min单纯微泡组经鼠尾静脉注射微泡造影剂0.5 ml;单纯超声组经鼠尾静脉注射生理盐水0.5 ml,同样条件超声辐照3 min对照组经鼠尾静脉注射生理盐水0.5 ml.于创伤后第1、3、5、7、14、21 d利用HE染色和免疫组化方法 观察各组创面肉芽组织生长及血管内皮生长因子(VEGF)表达的情况.结果 HE染色:伤后第7 d,超声破坏微泡组肉芽组织明显比其他3组厚,新生毛细血管均垂直于创面生长,其他3组毛细血管排列紊乱.免疫组化观察VEGF表达变化:超声破坏微泡组在第3 d形成表达高峰,其他3组表达高峰在第5～7 d.结论 超声破坏微泡可以提高大鼠背部皮肤的创面愈合质量;新生肉芽组织成熟早,创面愈合加速.超声破坏微泡时产生的高温、高压及某些化学效应可以刺激内源性VEGF分泌,促进血管生成,从而促进创面愈合.

Abstract：

Objective To investigate the effect of microbubble(Sono Vue) destruction with ultrasound on wound healing in rats. Methods Total 96 SD rats were accepted one rounded whole-layer skin incision on back each other and randomly divided into four groups:microbubble destruction with ultrasound(US + MB),microbubble(MB), ultrasound(US) and control group. Rats in US + MB group were injected with 0.5 ml microbubble contrast agent via tail vein,and then ultrasound irradiated for 3 minutes immediately. MB group were injected with 0.5 ml microbubble contrast agent. US group were injected with 0.5 ml physiological saline,and then ultrasound irradiated for 3 minutes immediately under the same condition. Control group were injected with 0.5 ml physiological saline. Feed each rat in single cage. On day 1,3,5,7,14 and 21 after wound creation,the excised wound tissues were analyzed by histology and VEGF expression in wounds by immunohistochemistry. Results HE staining: On day 7, wounds of US + MB group displayed the most accumulation of granulation tissue and all new capillaries were perpendicular to the wound surface, but the new capillaries of other 3 groups were disordered. Immunohistochemical examination of VEGF expression:the peak expression appeared on day 3 in US + MB group, other 3 groups were on day 5 to day 7.Conclusions US + MB treatment could improve the quality of wound healing and granulation tissues were maturated earlier than MB, US treatment and control group, which could accelerate wound healing. High temperature,high pressure and some kind of chemistry effecs induced by microbubble destruction with ultrasound can stimulate the secretion of endogenous VEGF, which may be the mechanism of promoting angiogenesis and wound healing.     

Eccentric calf muscle training compared with therapeutic ultrasound for chronic Achilles tendon pain--a pilot study

A number of studies have indicated that eccentric calf muscle training has beneficial effects in the management of Achilles tendon pain for recreational athletes. The purpose of this prospective randomised single blind pilot study was to investigate their potential effectiveness compared with therapeutic ultrasound in subjects with relatively sedentary lifestyles in an NHS hospital setting. Eleven men and five women (mean age 53+/-21 years) with Achilles tendon pain of minimum duration 4 months were randomised to one of two treatment groups; either eccentric loading or ultrasound. Administration of ultrasound and regular supervision of exercises occurred over a period of 6 weeks, with unsupervised exercises continuing for another 6 weeks. Outcome measurements were taken prior to and after 2, 4, 6 and 12 weeks after commencing treatment. They included: pain on a visual analogue scale, functional index of the leg and lower limb, and the five question EuroQol generalised health questionnaire. The difference in mean score was calculated together with 95% confidence intervals assuming a normal distribution. There were no statistically significant differences between groups or clear trends over time. In addition there was considerable overlap between the confidence intervals. This is not unexpected given the small sample size. Both interventions proved acceptable to the patients with no adverse effects. On this basis we intend conducting a full multi-centred study.     

The effect of therapeutic ultrasound intensity on the ultrastructural morphology of tendon repair

This study evaluated the effects of ultrasound intensity on the ultrastructural morphology of Achilles tendon healing. Twenty Sprague-Dawley rats with surgically hemi-transected Achilles tendons were randomly assigned into four groups of 0, 0.5, 1.2 and 2 W/cm(2) for ultrasound treatment, with five rats in each group. The treatments were administered with 1 MHz continuous ultrasound daily starting from day 5 after injury. On day 30, ultrathin slides of the Achilles tendons were prepared and examined with transmission electron microscopy. Results showed that the mean collagen fibril size of all treatment groups was higher than the control (p < 0.05). There was no significant difference in the collagen fibril size among the treatment groups. These findings suggest that therapeutic ultrasound can enhance the maturation of collagen fibrils of repairing tendons, and this was not dependent on the intensity of ultrasound applied.     

Comparison of therapeutic duration of therapeutic ultrasound in patients with knee osteoarthritis

[Purpose] The aim of study was to compare different durations of ultrasound in patients with knee osteoarthritis. [Subjects and Methods] One hundred patients diagnosed with bilateral knee osteoarthritis (OA) were enrolled in this study. Patients were divided into two groups. The first group (G1) received 4 minutes of ultrasound. The second group (G2) received the exact same treatment, but the duration of ultrasound was longer at 8 minutes. Patients in both groups underwent a total of 10 ultrasound over 2 weeks. Following treatment, all patients provided self-evaluations of pain via the Visual Analog Scale (VAS), overall physical function with WOMAC, disability via the Lequesne index (Leq), and depressive symptoms with the Beck Depression Index (BDI). [Results] There were no significant differences in VAS, WOMAC Leq, and BDI values between groups 1 and 2. After treatment, VAS, WOMAC, Leq, and BDI values improved for both treatment groups. However, following treatment, G2 had significantly greater values for WOMAC functional and total scores than G1. No statistically significant differences were observed for VAS scores while inactive, WOMAC pain and stiffness scores, and BDI values after treatment between both groups. VAS pain scores while active and Leq index values were significantly lower in G1 than G2. [Conclusion] Patients in both groups demonstrated improved functionality, pain and psychological status following a consistent, 2-week regimen of 4-minute or 8-minute treatments with ultrasound. Yet, patients that experienced longer treatment durations of 8 minutes demonstrated better outcomes in pain and the ability to carry out activities of daily living.Key words: Knee, Ultrasound, Osteoarthritis     

类风湿关节炎运动疗法应用初探

对18例患者除应用理疗和药物外,同时进行关节活动度训练、日常生活活动训练以及牵伸疗法2个月,对照组17例单用理疗、药物而没有进行运动疗法。结果表明两组有效率相似(100％),但显著改善率有明显差别,治疗组为72％,对照组为24％(P<0.01),尤其是ROM评价,前者比后者改善显著(P<0.01)。因此,运动疗法在类风湿病康复医疗中具有重要作用。     

大鼠跟腱断裂缝合中3种肌腱缝合方法的生物力学和组织学比较

背景:治疗手部伸肌腱断裂的手术缝合方法很多,临床效果不一,而且如何解决术后肌腱粘连,仍是临床难题.目的:比较跟腱断裂缝合中3种肌腱缝合方法的生物力学性质和组织学差异.设计、时间及地点:对比观察动物实验,于2008-04/06在哈尔滨医科大学附属第一临床医院中心实验室完成.材料:取45只Wistar大鼠,随机分为3组,Tang法组、改良Kessler法组、Bunnell法组.方法:无菌条件下,"S"形切开后肢后外侧跟腱处,潜行分离皮下组织,锐性横断跟腱,3组动物于切断后24 h,1周,3周分别以Tang法、改良Kessler法、Bunnell法缝合肌腱.每只大鼠的双后肢跟腱为实验组,右后肢跟腱作生物力学测试,左后肢跟腱作组织学检测.主要观察指标:肌腱断裂抗张强度及组织学变化.结果:Tang法、Kessler法和Bunnell法断裂抗张强度在24 h、1周、3周3个时间段都呈现同样的趋势,即早期断裂抗张强度都有减弱,后期强度逐渐增加.同时,术后及术后早期Tang法缝合肌腱的断裂抗张强度均明显高于其他两种方法,3周时,断裂抗张强度3种方法相近.组织学检测示,术后1周,Tang法、Kessler法和Bunnell法苏木精-伊红染色病理切片表现明显不同,Tang法较其他两种方法肉芽组织中新生血管比较多,血管腔扩张完整,有大量肉芽组织形成,炎症细胞浸润少.结论:Tang法缝合的肌腱断端血运良好,愈合快,断裂抗张强度较大,较其他两种方法更适用于早期功能锻炼.     

超声治疗应力屏蔽大鼠跟腱白细胞介素1β的表达

背景:临床上超声被用于软组织急慢性损伤的治疗,但是关于超声波治疗肌腱挛缩的实验研究较少.目的:观察超声对应力屏蔽后大鼠跟腱的作用和白细胞介素1β水平的影响.方法:将24只SD大鼠随机分为正常组,造模组和超声治疗组,后2组大鼠左后肢用跟腱环扎联合坐骨神经切断的方法造模,治疗组术后3周开始进行超声治疗,强度为1W/cm2,频率为1MHz,通胀比为20%,每周治疗5 d,1次/d,10 min/次,治疗共3周.术后6周取其左后肢部分跟腱组织,进行透射电镜检测,并采用ELISA法检测白细胞介素1β水平.结果与结论:超声治疗3周后胶原纤维排列较造模组整齐,细小纤维减少,接近于正常对照组.造模组白细胞介素1β水平显著高于正常组,超声治疗后白细胞介素1β水平显著降低.结果提示超声治疗可以对挛缩跟腱有治疗作用,可能与降低挛缩跟腱中白细胞介素1β水平有关.     

Low-intensity pulsed ultrasound enhances early healing of medial collateral ligament injuries in rats.

OBJECTIVE: To investigate the effect of low-intensity pulsed ultrasound exposure on the healing of injured medial collateral ligaments. METHODS: Thirteen male Sprague Dawley rats were used in the study. After surgical transection of the bilateral medial collateral ligaments, the ligament of 1 knee received low-intensity pulsed ultrasound exposure (30 mW/cm2 for 20 minutes daily), whereas no ultrasound was applied to the contralateral knee (control side). Eight rats were killed at 12 days after surgery, and 5 rats were killed at 21 days. The bilateral knees of 5 rats were used for mechanical testing at each of the 2 periods, and 12-day specimens of the remaining 3 rats were prepared for the electron microscopic examination. The knees of 5 additional rats were used to obtain mechanical data of the normal uninjured medial collateral ligament. RESULTS: On the 12th day, the low-intensity pulsed ultrasound-treated side exhibited significantly superior mechanical properties when compared with the control side in ultimate load, stiffness, and energy absorption (P < .05). However, the treatment did not afford any mechanical advantage when tested on the 21st day. The mean diameter of the fibril was significantly larger on the treatment side than on the control side (P < .05). CONCLUSIONS: Low-intensity pulsed ultrasound exposure is effective for enhancing the early healing of medial collateral ligament injuries.