THE EFFECTS OF CONVENTIONAL PHYSICAL THERAPY AND ECCENTRIC STRENGTHENING FOR INSERTIONAL ACHILLES TENDINOPATHY

Study Design:

Single‐blind, randomized, clinical trial.

Background:

The effect of eccentric training for mid‐portion Achilles tendinopathy is well documented; however, its effect on insertional Achilles tendinopathy is inconclusive. The primary purpose of this study was to investigate the effect of eccentric training on pain and function for individuals with insertional Achilles tendinopathy.

Methods:

All patients received a 12‐week conventional strengthening protocol. Patients who were randomly assigned to the experimental group received additional eccentric exercises. Patients completed the Short Form‐36 Health and Bodily Pain Surveys, the Foot and Ankle Outcomes Questionnaire, and the Visual Analog Scale at initial evaluation, after 6 weeks of therapy, and at 12 weeks after therapy.

Results:

Thirty‐six patients (20 control and 16 experimental; average age 54 years; 72% women) completed the study. Both groups experienced statistically significant decreases in pain and improvements in function. No statistically significant differences were noted between the groups for any of the outcome measures.

Conclusion:

Conventional physical therapy consisting of gastrocnemius, soleus and hamstring stretches, ice massage on the Achilles tendon, and use of heel lifts and night splints with or without eccentric training is effective for treating insertional Achilles tendinopathy.

Level of Evidence:

Level 2     

Pennation angle of the soleus in patients with unilateral Achilles tendinopathy

We measured the ultrasound scans of 23 (21 males, two females) physically active subjects (mean age: 40 years; range: 20 - 58) with unilateral Achilles tendinopathy to determine the pennation angle in the soleus muscles of the affected and non-affected limb. All scans were performed by one radiologist. The pennation angle was lower on the affected side in 15 patients, and higher on the non-affected side in eight patients. There was a significant difference in the angle of pennation of the soleus muscle on the affected side (15.9 degrees ) compared with that on the non-affected one (17.3 degrees ; p = 0.01). Patients with symptomatic Achilles tendinopathy are more likely to have decreased pennation angle of the soleus muscle on the affected side. This may have implications for appropriate management of Achilles tendinopathy.     

Pennation angle of the soleus in patients with unilateral Achilles tendinopathy

We measured the ultrasound scans of 23 (21 males, two females) physically active subjects (mean age: 40 years; range: 20 – 58) with unilateral Achilles tendinopathy to determine the pennation angle in the soleus muscles of the affected and non-affected limb. All scans were performed by one radiologist. The pennation angle was lower on the affected side in 15 patients, and higher on the non-affected side in eight patients. There was a significant difference in the angle of pennation of the soleus muscle on the affected side (15.9°) compared with that on the non-affected one (17.3°; p = 0.01). Patients with symptomatic Achilles tendinopathy are more likely to have decreased pennation angle of the soleus muscle on the affected side. This may have implications for appropriate management of Achilles tendinopathy.     

Effects of different types of exercise on muscle activity and balance control

[Purpose] This study analyzed the effects of isotonic, isokinetic, and isometric exercises of ankle joint muscles on lower extremity muscle activity and balance control. [Subjects and Methods] The subjects were 30 healthy adults (15 males) in their 20s who were randomly assigned to three different exercise method groups of 10 people each. The isokinetic exercise group performed three sets at an angular velocity of 60°/sec, including a single rest period after every set of 10 repetitions. The isometric exercise group performed three sets consisting of three 15 repetitions of a 15-second exercise followed by a 5-second rest. [Results] Multivariate analysis of variance revealed that depending on the exercise method, the non-dominant tibialis anterior, gastrocnemius muscle, and peroneus longus showed significant differences in muscle activity for weight-bearing non-dominant sides; when the dominant side was weight-bearing, the dominant gastrocnemius and peroneus longus showed significant differences in muscle activity; and the non-dominant and dominant sides showed significant differences in balance control depending on the duration of support in the area. [Conclusion] Muscle fatigue from the three exercise methods produced a decline in muscle activity and balance control; due to the fatigue before exercise, the side that did not perform the exercises was affected.Key words: Isotonic, Isokinetic, Isometric     

Achilles tendinopathy

Achilles tendon injury (tendinopathy) and pain occur in active individuals, when the tendon is subject to high or unusual load. Achilles tendinopathy can be resistant to treatment, and symptoms may persist despite both conservative and surgical intervention. The pathology of overuse tendinopathy is non-inflammatory, with a degenerative or failed healing tendon response. The diagnosis of Achilles tendinopathy requires excellent differential diagnosis and an understanding of the role of tendon imaging. Conservative treatment must include exercise, with a bias to eccentric contractions. Surgical treatment is effective after complete tendon rupture, but may not assist recovery from overuse tendinopathy. Further research into the clinical aspects of Achilles tendinopathy is required.     

Short vs. long length of rectus femoris during eccentric exercise in relation to muscle damage in healthy males

BACKGROUND: We investigated the effects of short vs. long length of rectus femoris during eccentric exercise of similar range of motion on selected muscle damage indicators. METHODS: Using an isokinetic dynamometer at 1.05 rad/s, 12 healthy male [mean (standard deviation), 21 (2) years] volunteers randomly underwent two exercise sessions, one on each leg, 14 days apart. During each session, subjects had to accomplish 12 sets of 10 maximal voluntary efforts in seated and prone positions to achieve short and long length of rectus femoris, respectively. Muscle damage indicators [serum creatine kinase activity, delayed onset muscle soreness, range of motion, eccentric peak torque, concentric peak torque and isometric peak torque] were assessed pre-exercise and 24, 48, 72 as well as 96 h post-exercise. FINDINGS: Compared to baseline data, creatine kinase, delayed onset muscle soreness, and range of motion disclosed significant changes at all time points after both exercise sessions (P<0.05). However, these muscle damage indicators demonstrated greater changes following exercise at short compared to long length of rectus femoris (P<0.05). Torque assessments also revealed that nine out of 12 and only two out of 12 measurements decreased significantly following short and long length eccentric exercise of rectus femoris, respectively (P<0.05). Short length eccentric exercise resulted in greater torque declines compared to long length during concentric and isometric evaluations (P<0.05). No such differences were observed when torque changes were evaluated eccentrically. INTERPRETATION: Short length of rectus femoris eccentric exercise induces greater muscle damage and peak torque declines than the corresponding long length in healthy adults.     

Muscle pain induced by novel eccentric exercise does not disturb the sleep of normal young men

This experiment sought to determine if delayed-onset muscle pain following novel eccentric exercise would disrupt sleep. Nine young adult men performed eccentric exercise and, during a separate week, concentric exercise consisting of 8 sets of 10 repetitions at 80% of 1-repetition maximum for 3 muscle groups. Sleep was assessed polysomnographically the night before and 2 nights following the exercise bouts. Muscle pain intensity in the biceps, triceps, and quadriceps muscle groups was significantly increased following eccentric exercise (all P <.02), and upper arm range of motion was significantly decreased following eccentric exercise (F = 19.19; df [degrees of freedom] = 2,16; P <.0001). A Condition-by-Trial interaction was observed for stage 1 sleep (F = 6.91; df = 2,16; P =.007), and minutes of stage 1 sleep were reduced following eccentric exercise and increased following concentric exercise. In general, however, the hypothesized sleep disruptions following eccentric exercise were not observed. It is concluded that delayed onset muscle pain induced by novel eccentric exercise does not disturb the sleep of normal young men.     

髌腱末端病运动员膝关节等速向心和离心运动时股四头肌表面肌电的变化

背景:髌腱末端病是腱止点部位的微细损伤,股四头肌群中的股内侧肌与股外侧肌之间的力量平衡发生变化,可直接导致髌骨产生异常运动从而对腱止点部位产生影响.目的:比较与分析髌腱末端病运动员膝关节力学特征和股四头肌表面肌电图的变化规律,为髌腱末端病的预防与治疗提供参考依据.设计、时间及地点:病例一对照观察,于2009-06/07在苏州大学体育学院运动机能评定实验室完成.对象:选择忠有髌腱末端病的男性运动员10人为髌腱末端病组,年龄(21.44±1.51)岁.配对选择10名无膝关节伤病的运动员作为正常对照组,年龄(21.37±1.36)岁.方法:对两组受试者分别进行膝关节力量和表面肌电测试,比较与分析膝关节屈肌力矩、伸肌力矩和股四头肌表面肌电的变化.主要观察指标:①等速运动时两组对象屈伸肌力矩的比较.②两组对象股四头肌表面肌电积分值的比较.③两组对象股内侧肉和股外侧肌表面肌电积分值比率的比较.结果:向心运动和离心运动时,末端病组屈伸肌峰力矩比值显著高于对照组(P＜0.05或P＜0.01),股内侧肌表面肌电积分值显著低于对照组(P＜0.05或P＜0.01),两组股外侧肌和股直肌表面肌电积分值差异均无显著性意义.向心运动和离心运动时,末端病组股内侧肌,股外侧肌比值均明显低于对照组(P＜0.05或P＜0.01).结论:髌腱末端病运动员膝关节屈肌与伸肌的力量差距较为突出,存在股内侧肌活动低下和股内侧肌与股外侧肌之间不平衡的现象.     

Leg Muscle Activation and Distance Setting of the Leg Cycle Ergometer for Use by the Elderly

[Purpose] This study verified the leg muscle activities of elderly subjects performing leg cycle ergometer exercise. [Subjects] Forty-one elderly persons were the subjects of this study. [Methods] For the three distances corresponding to knee flexion angles of 15, 45, and 70, the muscle activities of the rectus femoris, biceps femoris, tibialis anterior and lateral gastrocnemius were measured while the subjects exercised on a cycle ergometer. [Results] The rectus femoris and biceps femoris showed statistically significant increases as the distance between the cycle ergometer and the body increased, and the lateral gastrocnemius muscle activation showed a statistically significant increase as the distance from the body to the cycle ergometer decreased. [Conclusion] When the elderly have limb muscle weakness, leg cycle ergometer distances should be adjusted.Key words: Cycle ergometer, Electromyography, Selective muscle strengthening     

WHY ARE ECCENTRIC EXERCISES EFFECTIVE FOR ACHILLES TENDINOPATHY?

Achilles Tendinopathy is a complex problem, with the most common conservative treatment being eccentric exercises. Despite multiple studies assessing this treatment regime little is known about the mechanism of effect. This lack of understanding may be hindering therapeutic care and preventing optimal rehabilitation. Of the mechanisms proposed, most relate to tendon adaptation and fail to consider other possibilities. The current consensus is that tendon adaptation does not occur within timeframes associated with clinical improvements, therefore the clinical benefits must occur through another unidentified pathway. This clinical commentary critically reviews each of the proposed theories and highlights that muscle alterations are observed prior to onset of Achilles Tendinopathy and during the disease. Evidence shows that the observed muscle alterations change with treatment and that these adaptations have the ability to reduce tendon load and thereby improve tendon health. The purpose of this clinical commentary is to review previous theories regarding the mechanisms by which eccentric exercise might affect Achilles tendinopathy and offers a novel mechanism by which the plantarflexor muscles may shield the Achilles tendon.

Level of Evidence

5     

Eccentric exercises for the management of tendinopathy of the main body of the Achilles tendon with or without the AirHeel™ Brace. A randomized controlled trial. A: Effects on pain and microcirculation

Purpose. To compare eccentric training and the combination of eccentric training with the AirHeel? Brace for the management of tendinopathy of the main body of the Achilles tendon.

Methods. We recruited 116 subjects with unilateral tendinopathy of the main body of the Achilles tendon, who were randomized in two groups. Group A performed a regimen of daily eccentric training associated with the AirHeel? Brace (Donjoy Orthopedics, Vista, CA, USA). Group B performed the same eccentric training without the AirHeel? Brace. Tendon microcirculatory mapping was performed using combined Laser-Doppler and spectrophotometry. Pre- and post-operative FAOS score and VAS score were used to evaluate the patients.

Results. The FAOS score and the VAS score showed significant improvements from pre-operative to post-operative values in both groups (A 5.1 ± 2 vs. 2.9 ± 2.4, 43% reduction and B: 5.4 ± 2.1 vs. 3.6 ± 2.4, 33% reduction, both p = 0.0001). There were no statistically significant differences in FAOS score and VAS score when comparing the two groups after the end of the intervention. In Group A, tendon oxygen saturation in the main body of the Achilles tendon showed significant increase from pre- to post-management values (68 ± 12 vs.74 ± 8%, p = 0.003). Post-capillary venous filling pressures showed significant reduction from pre- to post-intervention values.

Conclusion. Eccentric training, associated or not with the AirHeel? Brace, produces the same effect in patients with tendinopathy of the main body of the Achilles tendon. The combination of eccentric training with the AirHeel? Brace can optimize tendon microcirculation, but these micro-circulator advantages do not translate into superior clinical performance when compared with eccentric training alone.     

Exercise-induced muscle soreness after concentric and eccentric isokinetic contractions

The purpose of this two-part study was to determine whether the amount of exercise-induced muscle soreness differs between subjects who perform concentric and eccentric isokinetic contractions of their quadriceps femoris muscles. In experiment 1, subjects were randomly assigned to either an eccentric or a concentric exercise group and both groups exercised at the same power level. In experiment 2, subjects were randomly assigned to either an eccentric or a concentric exercise group and both groups exercised with maximal effort. Muscle soreness ratings, obtained by using a visual analogue scale, were taken immediately before exercise and at 24 and 48 hours postexercise. Changes in muscle soreness ratings between exercise groups from preexercise to postexercise periods were compared in both experiments, using a one-way between-subjects analysis of variance. There was no difference in the change in muscle soreness from preexercise to post-exercise periods between groups exercising at equal power levels. Subjects who exercised using eccentric contractions with maximal effort demonstrated greater increases in muscle soreness than those who performed concentric contractions. The results suggest that exercise intensity, rather than contraction type, may be the dependent factor in producing exercise-induced muscle soreness.     

Quadriceps strength training using two forms of bilateral exercise

The purpose of this study was to determine the effectiveness of quadriceps strength training in 15 women using bilateral constant resistance computerized exercise equipment that enabled only concentric contractions. To facilitate this investigation, data from an experimental control group (n = 14), using bilateral variable resistance exercise equipment which enables both concentric and eccentric muscle contractions, and a nonexercise control group (n = 17) were incorporated into the study design. Through a random selection process, subjects were assigned to one of three groups that participated in this 10-week study. Analysis, including univariate and multivariate statistical techniques, revealed no significant changes in strength between the two experimental groups. However, compared with the nonexercise group, there were significant increases in strength in the experimental exercise groups; yet, these increases were significant in both groups only on the right legs. In addition, the development of transient knee pain in two subjects engaged in both concentric and eccentric exercise training required their removal from the study. This finding, in concert with previous experimental evidence of an association between eccentric exercise and the development of transient pain, must be integrated into future studies. Results suggest that further investigation is necessary to reveal the neurologic or biomechanical factors which may result in unequal training stimuli to the limbs with bilateral strength training on various types of equipment.     

Determination of the fascicle length of the gastrocnemius muscle during calf raise exercise using ultrasonography

[Purpose] The purpose of this study was to find a strength training protocol which maintains isometric contraction of the triceps surae during dorsal flexion of the ankle. [Subjects] The left feet of 22 young normal volunteers who did not have orthopedic injuries or lower limb pain participated in this study. [Methods] All subjects performed four sets of five repetitions of four sets calf-raise (CR) exercise at were (1) 60 bpm without a pedestal, (2) 60 bpm with a pedestal, (3) 90 bpm without a pedestal, and (4) 90 bpm with a pedestal. The fascicle length of the lateral head of the gastrocnemius and ankle angle were measured using ultrasonography and a video camera. The CR exercise was divided into two or three phases using the kinematics of the ankle. The average change in fascicle length over the five repetitions of each phase were compared. [Results] The change of the fascicle length during the hyper-dorsiflexion phase was significantly smaller than during the other two phases. [Conclusion] It is possible that eccentric CR exercises have progressed to motor learning of the isometric contraction during counter movement, and improved the release of elastic energy of the Achilles tendon during running, jumping, and other athletic activities.Key words: Gastrocnemius, Isometric contraction, Eccentric calf raise exercise     

Force production during squats performed with a rotational resistance device under stable versus unstable conditions

[Purpose] Force production during a squat action on a rotational resistance device (RRD) under stable and unstable conditions. [Subjects and Methods] Twenty-one healthy males were asked to perform six sets of six repetitions of squats on an RRD on either stable or unstable surfaces. The stable and unstable sets were performed on different days. Muscular outputs were obtained from a linear encoder and a strain gauge fixed to a vest. [Results] Overall, the results showed no significant differences for any of the dependent variables across exercise modes. Force_mean outputs were higher in the concentric phase than in the eccentric phase for each condition, but there were no differences in velocity, time or displacement. The force_peak was similar in the eccentric and concentric phases of movement under both stable and unstable conditions. There were no significant differences in force_mean between sets per condition or between conditions. [Conclusion] These results suggest that performing squats with a RRD achieves similar force_mean and force_peak under stable and unstable conditions. The force_peak produced is also similar in concentric and eccentric phases.Key words: Strength training, Accelerometer, Instability     

Effect of Extracorporeal Shock Wave Therapy on Denervation Atrophy and Function Caused by Sciatic Nerve Injury

[Purpose] The present study examined the effects of treatment using extracorporeal shock wave therapy (ESWT) on the muscle weight and function of the hind limb in sciatic nerve injury. [Subjects] Forty rats with sciatic nerve crushing injury were randomly divided into two groups: an ESWT group (n=20), and a control group (n=20). [Methods] The ESWT group received extracorporeal shock wave treatment, and the control group did not receive any treatment after injury. Experimental animals were measured for muscle weight on an electronic scale and were tested for function on a sciatic functional index (SFI). [Results] All groups showed significant increases in the weights of the left soleus and gastrocnemius muscles, and decreases in the weights of the right soleus and gastrocnemius muscles (p<0.05). Comparison of SFI scores and muscle weights between the groups showed significant differences in SFI scores, and the right soleus and gastrocnemius muscles (p<0.05) [Conclusion] Exercise programs that use ESWT can be said to be effective at improving the function of the sciatic nerve and preventing the denervation atrophy.Key words: ESWT, Sciatic nerve, Peripheral nerve     

The Effects of Augmented Reality-based Otago Exercise on Balance,Gait, and Falls Efficacy of Elderly Women

[Purpose] The purpose of this study was to determine the effects of augmented reality-based Otago exercise on balance, gait, and falls efficacy of elderly women. [Subjects] The subjects were 21 elderly women, who were randomly divided into two groups: an augmented reality-based Otago exercise group of 10 subjects and an Otago exercise group of 11 subjects. [Methods] All subjects were evaluated for balance (Berg Balance Scale, BBS), gait parameters (velocity, cadence, step length, and stride length), and falls efficacy. Within 12 weeks, Otago exercise for muscle strengthening and balance training was conducted three times, for a period of 60 minutes each, and subjects in the experimental group performed augmented reality-based Otago exercise. [Results] Following intervention, the augmented reality-based Otago exercise group showed significant increases in BBS, velocity, cadence, step length (right side), stride length (right side and left side) and falls efficacy. [Conclusion] The results of this study suggest the feasibility and suitability of this augmented reality-based Otago exercise for elderly women.Key words: Augmented reality, Otago exercise, Falls efficacy     

Effect of Virtual Reality Exercise Using the Nintendo Wii Fit on Muscle Activities of the Trunk and Lower Extremities of Normal Adults

[Purpose] The present study aimed to determine the effect of virtual reality exercise using the Nintendo Wii Fit on the muscle activities of the trunk and lower extremities of normal adults. [Subjects] The subjects of the study were 24 normal adults who were divided into a virtual reality exercise group (VREG, n=12) and a stable surface exercise group (SEG, n=12). [Methods] The exercises of the VREG using the Nintendo Wii Fit and the SEG using a stable surface were conducted three times a week for six weeks. Electromyography was used to measure the muscle activities of the tibialis anterior (TA), medial gastrocnemius (MG), erector spinae (ES), and rectus abdominal (RA) muscles. [Results] VREG showed significant within group differences in TA and MG muscle activities, while the SEG showed a significant difference in the muscle activity of the MG. [Conclusion] Virtual reality exercise using the Nintendo Wii Fit was an effective intervention for the muscle activities of the TA and MG of normal adults.Key words: Virtual reality exercise, Stable surface exercise, Muscle activity     

热应激预处理对离心运动大鼠骨骼肌自由基代谢的影响

背景:研究表明热预处理能够提高肌肉抗损伤的能力,但具体的机制尚不清楚。目的:观察热应激预处理对离心运动大鼠骨骼肌超氧化物歧化酶活性及丙二醛含量的影响。方法:雄性Wistar大鼠随机分为对照组、离心运动组、预热应激+离心运动组。热应激温度为43℃,时间约35min。采用-16°下坡跑台跑做大负荷间歇性离心运动,跑速为26.8m/min,运动5min,间歇1min,共进行10组。分别于运动前1h、运动后1,24,48h取大鼠腓肠肌,采用硫代巴比妥酸法测定大鼠丙二醛含量,黄嘌呤氧化酶法测定超氧化物歧化酶活性。结果与结论:与对照组比较,离心运动组大鼠腓肠肌丙二醛含量显著增高(P<0.05),并随运动后时间的延长逐渐升高,超氧化物歧化酶活性随运动后时间的延长显著降低(P<0.05)。与离心运动组比较,预热应激+离心运动组大鼠腓肠肌超氧化物歧化酶活性显著增高(P<0.05),丙二醛含量显著降低(P<0.05)。说明热应激预处理可增强骨骼肌超氧化物歧化酶活性,降低丙二醛含量,对离心运动损伤有保护作用。