Eccentric training of the gastrocnemius-soleus complex in chronic Achilles tendinopathy results in decreased tendon volume and intratendinous signal as evaluated by MRI

Influence of aerobic cycle exercise training on patellar tendon cross-sectional area in older women

Nine to 12 weeks of resistance exercise training in young individuals induces quadriceps muscle (∼6%) and region-specific patellar tendon (4-6%) hypertrophy. However, 12 weeks of resistance exercise training (∼1 h total exercise time) in older individuals (60-78 years) induces quadriceps muscle hypertrophy (9%) without impacting patellar tendon size. The current study examined if a different loading paradigm using cycle exercise would promote patellar tendon hypertrophy or alter the internal tendon properties, measured with magnetic resonance imaging signal intensity, in older individuals. Nine women (70 ± 2 years) completed 12 weeks of aerobic upright cycle exercise training (∼28 h total exercise time). Aerobic exercise training increased (P < 0.05) quadriceps muscle size (11 ± 2%) and VO2max (30 ± 9%). Mean patellar tendon cross-sectional area (CSA) (2 ± 1%) and signal intensity (-1 ± 2%) were unchanged (P > 0.05) over the 12 weeks of training. Region-specific CSA was unchanged (P > 0.05) at the proximal (-1 ± 3%) and mid regions (2 ± 2%) of the tendon but tended (P = 0.069) to increase at the distal region (5 ± 3%). Region-specific signal intensity differed along the tendon but was unchanged (P > 0.05) with training. Although more studies are needed, exercise-induced patellar tendon hypertrophy, compared with skeletal muscle, appears to be attenuated in older individuals, while the loading pattern associated with aerobic exercise seems to have more impact than resistance exercise in promoting patellar tendon hypertrophy.

Electromyographic analysis of an eccentric calf muscle exercise in persons with and without Achilles tendinopathy

OBJECTIVES

To compare surface electromyographic (EMG) activity of the gastrocnemius and soleus muscles between persons with and without Achilles tendinopathy (AT) during an eccentric muscle exercise in different knee joint positions.

DESIGN

Repeated measures design.

SETTING

Research laboratory.

PARTICIPANTS

Participants (n = 18) diagnosed with AT and 18 control subjects were recruited.

MAIN OUTCOME MEASURES

Gastrocnemius and soleus muscle activity was examined by surface (EMG) during extended and flexed knee joint conditions while performing the eccentric training technique. The EMG data were expressed as a percentage of a maximum voluntary contraction (MVC).

RESULTS

EMG activity was notably higher (mean difference: 10%, effect size: 0.59) in those subjects with AT. Irrespective of the presence of AT, there was a significant interaction effect between muscle and joint position. The gastrocnemius muscle was significantly more active in the extended knee condition and soleus muscle activity was unchanged across joint positions.

CONCLUSIONS

The results indicated that the presence of AT influenced calf muscle activity levels during performance of the eccentric exercise. There were differences in muscle activity during the extended and flexed knee conditions. This result does support performing Alfredson, Pietila, Jonsson, and Lorentzon (1998) eccentric exercise in an extended knee position but the specific effects of the knee flexed position on the Achilles tendon during eccentric exercise have yet to be determined, particularly in those with AT.

Medial and lateral gastrocnemius activation differences during heel-raise exercise with three different foot positions

Despite little objective support, heel-raise exercises are commonly performed using varying foot positions in an attempt to alter medial (MG) and lateral (LG) gastrocnemius involvement. This investigation compared MG and LG activation during the concentric phase (CP) and eccentric phase (EP) of the heel-raise exercise using neutral (NE), internally rotated (IR), and externally rotated (ER) foot positions. Twenty healthy subjects (10 men, 10 women; age = 23.7 ± 3.1 years) with resistance training experience performed free-weight (130-135% body mass) heel-raise exercise on a 3.81-cm block. Surface electromyography activity was recorded during 10 repetitions of each foot position. Electromyography activity from 5 successful repetitions was normalized to maximum voluntary isometric contraction, ensemble averaged within phase (CP, EP), and the mean amplitude determined. Significant (p < 0.05) muscle-by-foot position interactions were revealed for both phases. The ER position prompted significantly greater MG activation than LG during both phases, whereas the IR position elicited significantly greater LG activation than MG. These data support the notion that altering foot position during heel-raise exercise will prompt varying degrees of MG and LG activation. Although this study cannot predict whether muscle-activation differences between foot positions will translate into greater training adaptations, it does provide some initial objective evidence upon which practitioners can base the selection of gastrocnemius exercises.

Periodization: current review and suggested implementation for athletic rehabilitation

BACKGROUND

Clinicians are constantly faced with the challenge of designing training programs for injured and noninjured athletes that maximize healing and optimize performance. Periodization is a concept of systematic progression-that is, resistance training programs that follow predictable patterns of change in training variables. The strength training literature is abundant with studies comparing periodization schemes on uninjured, trained, and untrained athletes. The rehabilitation literature, however, is scarce with information about how to optimally design resistance training programs based on periodization principles for injured athletes. The purpose of this review is to discuss relevant training variables and methods of periodization, as well as periodization program outcomes. A secondary purpose is to provide an anecdotal framework regarding implementation of periodization principles into rehabilitation programs.

EVIDENCE ACQUISITION

A Medline search from 1979 to 2009 was implemented with the keywords periodization, strength training, rehabilitation, endurance, power, hypertrophy, and resistance training with the Boolean term AND in all possible combinations in the English language. Each author also undertook independent hand searching of article references used in this review.

RESULTS

Based on the studies researched, periodized strength training regimens demonstrate improved outcomes as compared to nonperiodized programs.

CONCLUSIONS

Despite the evidence in the strength training literature supporting periodization programs, there is a considerable lack of data in the rehabilitation literature about program design and successful implementation of periodization into rehabilitation programs.

The long-term clinical and MRI results following eccentric calf muscle training in chronic Achilles tendinosis

PURPOSE

To evaluate the long-term results following eccentric calf-muscle training in patients with chronic Achilles tendinopathy.

MATERIALS AND METHODS

A total of 24 patients with chronic Achilles tendinopathy were included in a study evaluating MRI findings and clinical symptoms before and after 3 months of daily eccentric calf-muscle strength training. Median duration of symptoms was 18 months (range 6-120). Four of the patients did not perform the prescribed treatment for different reasons and were followed for 14 months. The resulting 20 treated patients completed 4.2-year (range 29-58 months) follow up. Tendon volume was evaluated by using 3D seed growing technique and signal abnormalities were visually semi-quantitatively graded. Level of pain and performance was categorized using a questionnaire completed by the patient.

RESULTS

In the symptomatic treated patients, median intensity level of pain decreased from moderate/severe at time of inclusion to mild at follow up (p < 0.05). Median level of performance increased from severe impairment at time of inclusion to normal at follow up (p < 0.05). 12 out of 20 patients had raised intratendinous signal at time of inclusion compared to 2 out of 20 patients at follow up (p < 0.001). Mean tendon-volume measured 6.7 cm(3) (SD 2.0) at time of inclusion and 6.4 cm(3) (SD 2.0) at follow up (p = 0.18). The four symptomatic non-treated tendons did not improve regarding pain, performance, intratendinous signal or tendon volume.

CONCLUSION

We found decreased pain, improved performance and decreased intratendinous signal both compared to index examination and immediately after the 3 months training regimen in a 4.2-year clinical and MRI follow up, in a group of patients treated with heavy loaded eccentric calf-muscle training for chronic Achilles tendinopathy. The improvements were greater at 4.2-year follow up, despite no further active treatment, than immediately after the treatment. This may indicate a good long-term prognosis for Achilles tendinosis patients.

Conservative treatment of Achilles tendinopathy: emerging techniques

Achilles tendinopathy is a painful condition that occurs commonly in both active and inactive individuals. It seems that this condition is painful as a result of ingrowth of neural structures and neovessels leading to poor healing, rather than from inflammatory mediators. Traditional conservative measures are often successful. There is a subset of patients who fail to respond to these measures, however, and this has led to the investigation of newer conservative techniques. This article provides a review of many of the emerging techniques in the treatment of Achilles tendinopathy.

Effect of eccentric exercise program for early tibialis posterior tendinopathy

BACKGROUND

Morphology and vascularization of painful tibialis posterior (TP) tendons before and after an intervention targeting the degenerated tendon were examined. Functional status and pain level were also assessed.

MATERIALS AND METHODS

A10-week twice daily, progressive eccentric tendon loading, calf stretching program with orthoses was implemented with ten, early stage TP tendinopathy subjects. TP tendons were imaged by grayscale and Doppler ultrasound at INITIAL and POST evaluations to assess the tendon's morphology and signs of neovascularization. The Foot Functional Index (FFI), Physical Activity Scale (PAS), 5-Minute Walk Test, and single heel raise (SHR) test were completed at INITIAL and POST evaluations. The Global Rating Scale (GRS) was completed at 6 months followup. One-way ANOVA was used to compare the FFI at INITIAL, POST, and 6-MONTH time points. Paired t-tests were used to compare means between the remaining variables. The level of significance was p = 0.05.

RESULTS

There was a significant difference in FFI total, pain, and disability at the three time-points. Post-hoc paired t-tests revealed that the FFI scores were lower for the total score and pain and disability subcategories when comparing from INITIAL to POST and INITIAL to 6-MONTH evaluations (p < 0.05 for all). The number of SHR increased significantly on the involved side from INITIAL to POST evaluation (p = 0.041). The GRS demonstrated minimum clinically important differences for improvements in symptoms at 6-MONTH. Tendon morphology and vascularization remained abnormal following the intervention.

CONCLUSION

A 10-week tendon specific eccentric program resulted in improvements in symptoms and function without changes in tendon morphology or neovascularization.

Forward lunge: a training study of eccentric exercises of the lower limbs

A few studies have shown that eccentric exercise is effective for prevention and treatment of muscle injuries. Most earlier studies on eccentric exercises have used training with advanced equipment. Forward lunges are considered eccentric exercises, and they may be performed without any equipment. These exercises are commonly used by sprint runners. We performed a prospective, randomized, 6-week training study comparing the effects of walking or jumping forward lunges on hamstring and quadriceps strength and function. Thirty-two soccer players were included in the study. The forward lunge training was done as an addition to ordinary soccer training twice a week for 6 weeks. The outcome was measured by the maximal hamstring and quadriceps strength tests and by functional tests with 1-leg hop tests and 30-m sprint runs. Overall muscle pain was evaluated using a visual analogue scale score, and local pain was estimated with an algometer. Whereas the walking lunge improved hamstring strength, the jumping lunge resulted in sprint running improvements. Algometer testing showed a general increase in the pain detection thresholds of all subjects, including the controls. Thus, precautions should be taken when algometers are used for temporal studies of pain. Walking and jumping forward lunges can be used for improving hamstring strength and running speed in young soccer player. The findings may have relevance when designing protocols for prevention and rehabilitation of muscle injuries.

Eccentric exercise protocols for chronic non-insertional Achilles tendinopathy: how much is enough?

Eccentric exercises for the calf muscles have been shown to be effective for chronic non-insertional Achilles tendinopathy (AT). However, the relative effectiveness of various dosages is unknown. A systematic review of randomized-controlled trials (RCTs) was designed to determine whether an optimum dose of eccentric exercises could be recommended. Three selected RCTs showed positive effects of very similar eccentric exercise protocols for chronic non-insertional AT. Owing to insufficient reported compliance data, a conclusion on the relative effectiveness of various compliances was not feasible. According to our review, the relative effectiveness of various dosages of eccentric exercises for AT is still unclear. However, it appears that highly variable compliance rates result in similar positive outcomes; these findings, therefore, highlight the need for further investigations.

Mid-portion Achilles tendinopathy--current options for treatment

PURPOSE

To report on the present option for management of tendinopathy of the main body of the Achilles tendon.

BACKGROUND

Tendinopathy of the main body of tendo Achillis affects athletic and sedentary patients. Mechanical loading is thought to be a major causative factor. However, the exact mechanical loading conditions which cause tendinopathy are poorly defined. Repetitive mechanical loading induces a non-inflammatory pathology, and repetitive microtrauma ultimately exceeds the healing response. The management of Achilles tendinopathy is primarily conservative. Although many non-operative options are available, few have been tested under controlled conditions. This review article specifically focuses on eccentric training, and on shock wave therapy. Surgical intervention can be successful in refractory cases. However, surgery does not usually completely eliminate symptoms and complications are not rare.

CONCLUSIONS

Further studies are needed to discern the optimal non-operative and surgical management of midsubstance Achilles tendinopathy.

Influence of aging on the in vivo properties of human patellar tendon

Tendons are important for optimal muscle force transfer to bone and play a key role in functional ability. Changes in tendon properties with aging could contribute to declines in physical function commonly associated with aging. We investigated the in vivo mechanical properties of the patellar tendon in 37 men and women [11 young (27 +/- 1 yr) and 26 old (65 +/- 1 yr)] using ultrasonography and magnetic resonance imaging (MRI). Patella displacement relative to the tibia was monitored with ultrasonography during ramped isometric contractions of the knee extensors, and MRI was used to determine tendon cross-sectional area (CSA) and signal intensity. At peak force, patellar tendon deformation, stress, and strain were 13 (P = 0.05), 19, and 12% less in old compared with young (P < 0.05). Additionally, deformation, stiffness, stress, CSA, and length were 18, 35, 41, 28, and 11% greater (P < 0.05), respectively, in men compared with women. After normalization of mechanical properties to a common force, no age differences were apparent; however, stress and strain were 26 and 22% higher, respectively, in women compared with men (P < 0.05). CSA and signal intensity decreased 12 and 24%, respectively, with aging (P < 0.05) in the midregion of the tendon. These data suggest that differences in patellar tendon in vivo mechanical properties with aging are more related to force output rather than an age effect. In contrast, the decrease in signal intensity indirectly suggests that the internal milieu of the tendon is altered with aging; however, the physiological and functional consequence of this finding requires further study.

Treatment of tendinopathy: what works, what does not, and what is on the horizon

Tendinopathy is a broad term encompassing painful conditions occurring in and around tendons in response to overuse. Recent basic science research suggests little or no inflammation is present in these conditions. Thus, traditional treatment modalities aimed at controlling inflammation such as corticosteroid injections and nonsteroidal antiinflammatory medications (NSAIDS) may not be the most effective options. We performed a systematic review of the literature to determine the best treatment options for tendinopathy. We evaluated the effectiveness of NSAIDS, corticosteroid injections, exercise-based physical therapy, physical therapy modalities, shock wave therapy, sclerotherapy, nitric oxide patches, surgery, growth factors, and stem cell treatment. NSAIDS and corticosteroids appear to provide pain relief in the short term, but their effectiveness in the long term has not been demonstrated. We identified inconsistent results with shock wave therapy and physical therapy modalities such as ultrasound, iontophoresis and low-level laser therapy. Current data support the use of eccentric strengthening protocols, sclerotherapy, and nitric oxide patches, but larger, multicenter trials are needed to confirm the early results with these treatments. Preliminary work with growth factors and stem cells is promising, but further study is required in these fields. Surgery remains the last option due to the morbidity and inconsistent outcomes. The ideal treatment for tendinopathy remains unclear.

LEVEL OF EVIDENCE

Level II, systematic review.

Chronic tendinopathy tissue pathology, pain mechanisms, and etiology with a special focus on inflammation

Continuing progress in research in molecular biology and biomechanics has provided considerable new information and has given rise to new hypotheses in chronic tendinopathy. Overloading is still, however, crucial in the development of tendinopathy. Most of the histologic findings in tendinopathy represent chronic degeneration, regeneration, and microtears of the tendinous tissue. The prevailing opinion is that no histological evidence of acute inflammation has been documented, but in newer studies using immunohistochemistry and flow cytometry inflammatory cells have been detected. The existing data indicate that the initiators of the tendinopathic pathway include many proinflammatory agents (e.g. cytokines, prostaglandins, different growth factors, and neuropetides). Because of the complex interaction between the classic proinflammatory agents and the neuropeptides, it seems impossible and somewhat irrelevant to distinguish sharply between chemical and neurogenic inflammation. Furthermore, glucocorticoids are, at the moment, the most effective treatment in tendinopathy with regard to reduction of pain, tendon thickness, and neovascularization. This review indicates - despite a great deal of uncertainty regarding the concepts - that an inflammatory process may be related not only to the development of tendinopathy but also chronic tendinopathy. More attention should be directed towards the "tendinitis myth" in the future.

The role of tendon microcirculation in Achilles and patellar tendinopathy

Tendinopathy is of distinct interest as it describes a painful tendon disease with local tenderness, swelling and pain associated with sonographic features such as hypoechogenic texture and diameter enlargement. Recent research elucidated microcirculatory changes in tendinopathy using laser Doppler flowmetry and spectrophotometry such as at the Achilles tendon, the patellar tendon as well as at the elbow and the wrist level. Tendon capillary blood flow is increased at the point of pain. Tendon oxygen saturation as well as tendon postcapillary venous filling pressures, determined non-invasively using combined Laser Doppler flowmetry and spectrophotometry, can quantify, in real-time, how tendon microcirculation changes over with pathology or in response to a given therapy. Tendon oxygen saturation can be increased by repetitive, intermittent short-term ice applications in Achilles tendons; this corresponds to 'ischemic preconditioning', a method used to train tissue to sustain ischemic damage. On the other hand, decreasing tendon oxygenation may reflect local acidosis and deteriorating tendon metabolism. Painful eccentric training, a common therapy for Achilles, patellar, supraspinatus and wrist tendinopathy decreases abnormal capillary tendon flow without compromising local tendon oxygenation. Combining an Achilles pneumatic wrap with eccentric training changes tendon microcirculation in a different way than does eccentric training alone; both approaches reduce pain in Achilles tendinopathy. The microcirculatory effects of measures such as extracorporeal shock wave therapy as well as topical nitroglycerine application are to be studied in tendinopathy as well as the critical question of dosage and maintenance. Interestingly it seems that injection therapy using color Doppler for targeting the area of neovascularisation yields to good clinical results with polidocanol sclerosing therapy, but also with a combination of epinephrine and lidocaine.

Eccentric training decreases paratendon capillary blood flow and preserves paratendon oxygen saturation in chronic achilles tendinopathy

STUDY DESIGN

A controlled, randomized, prospective study,

OBJECTIVE

To assess the changes in paratendon microcirculation after 12 weeks of daily painful eccentric training in individuals with chronic Achilles tendinopathy.

BACKGROUND

Changes in tendon and paratendon microcirculation are evident in insertional and midportion Achilles tendinopathy. Whether the paratendon is involved in eccentric training response is not known.

METHODS

Twenty patients with chronic Achilles tendinopathy were recruited for a prospective, controlled trial using eccentric exercise. A laser Doppler system assessed capillary blood flow (flow), tissue oxygen saturation (SO2), and postcapillary venous filling pressure (rHb) at 8 paratendon locations at depths of 2 and 8 mm.

RESULTS

Pain in the eccentric-training group was reduced by 48% (from a mean of 4.1 +/- 2.9 to 2.1 +/- 2.2, P<.05). Deep paratendon blood flow decreased at the midportion paratendon location (P<.05). Superficial blood flow at the medial distal midportion position (by 31%, P = .008) and the lateral proximal midportion location (by 45%, P = .016) were significantly decreased postintervention, No significant change of superficial or deep paratendon oxygenation was found after intervention as compared to baseline. Deep paratendon postcapillary venous filling pressures were significantly reduced following eccentric training (P<.05).

CONCLUSION

An eccentric-training program performed daily over 12 weeks reduced the increased paratendinous capillary blood flow in Achilles tendinopathy by as much as 45% and decreased pain level based on a visual analog scale. Local paratendon oxygenation was preserved while paratendinous postcapillary venous filling pressures were reduced after 12 weeks of eccentric training, which appears to be beneficial from the perspective of microcirculation.

Achilles tendon rupture following surgical management for tendinopathy: a case report

Background

Achilles tendinopathy is understood to be a failed healing response. Operative management is utilised following the failure of non-operative methods.

Case Presentation

We present a case of Achilles tendon rupture, sustained whilst isometrically loading the Achilles tendon during an eccentric loading exercise programme. Conclusion: Bilateral surgical exploration and debridement had previously been performed after conservative management of bilateral Achilles tendinopathy had been unsuccessful.

A treatment algorithm for managing Achilles tendinopathy: new treatment options

Achilles tendinopathy affects athletes, recreational exercisers and even inactive people. The pathology is not inflammatory; it is a failed healing response. The source of pain in tendinopathy could be related to the neurovascular ingrowth seen in the tendon's response to injury. The treatment of Achilles tendinopathy is primarily conservative with an array of effective treatment options now available to the primary care practitioner. If conservative treatment is not successful, then surgery relieves pain in the majority of cases. Directing a patient through the algorithm presented here will maximise positive treatment outcomes.

The evolution of eccentric training as treatment for patellar tendinopathy (jumper's knee): a critical review of exercise programmes

BACKGROUND AND AIM

Eccentric training has become a popular treatment for patellar tendinopathy. Our purpose was to review the evolution of eccentric strength training programmes for patellar tendinopathy with a focus on the exercise prescriptions used, to help clinicians make appropriate choices and identify areas needing further research.

METHODS

A computerised search of the entire MEDLINE database was performed on 1 September 2006 to identify prospective and randomised clinical trials with a focus on clinical outcome of eccentric training for patellar tendinopathy.

RESULTS

7 articles with a total of 162 patients and in which eccentric training was one of the interventions, all published after 2000, were included. The results were positive, but study quality was variable, with small numbers or short follow-up periods. The content of the different training programmes varied, but most were home-based programmes with twice daily training for 12 weeks. A number of potentially significant differences were identified in the eccentric programmes used: drop squats or slow eccentric movement, squatting on a decline board or level ground, exercising into tendon pain or short of pain, loading the eccentric phase only or both phases, and progressing with speed then loading or simply loading.

CONCLUSION

Most studies suggest that eccentric training may have a positive effect, but our ability to recommend a specific protocol is limited. The studies available indicate that the treatment programme should include a decline board and should be performed with some level of discomfort, and that athletes should be removed from sports activity. However, these aspects need further study.

Effects of short-term treatment strategies over 4 weeks in Achilles tendinopathy

BACKGROUND

The therapeutic efficacy of non-surgical treatment strategies in Achilles tendinopathy (AT) has not been well clarified. Time-consuming and costly combinations of treatment for pain, physiotherapy and biomechanical procedures are often applied.

OBJECTIVE

To analyse the efficacy of single therapeutic regimens commonly used over a short period of 4 weeks.

METHODS

31 male runners (mileage >32 km/week) with unilateral, untreated AT completed 4 weeks of either physiotherapy (10 treatments: deep-friction, pulsed ultrasound, ice, sensory motor training; (P)), wearing custom fit semirigid insoles (I) or remained without treatment (control group C). Before and after treatment, all patients underwent a treadmill test and a plantar flexion strength exercise. Subjective pain (Pain Disability Index, Pain Experience Scale), as well as strength performance capacity (peak torque), was analysed (mean, 95% CI, repeated measures analysis of variance, alpha = 0.05).

RESULTS

Pain was reduced to <50% of the baseline value after physiotherapy or after wearing insoles (p<0.05). Individual pain reduction was >50% (25%) in 89% (100%) of subjects in I and 55% (73%) in P. Higher eccentric plantar flexion peak torques after treatment were observed in I and P.

CONCLUSIONS

Most patients with AT experience a reduction in pain after only 4 weeks of differentiated, non-surgical treatment consisting of physiotherapy or semirigid insoles.

Chronic tendinopathy: effectiveness of eccentric exercise

OBJECTIVES

To determine the effectiveness of eccentric exercise (EE) programmes in the treatment of common tendinopathies.

DATA SOURCES

Relevant randomised controlled trials (RCTs) were sourced using the OVID website databases: MEDLINE (1966-Jan 2006), CINAHL (1982-Jan 2006), AMED (1985-Jan 2006), EMBASE (1988-Jan 2006), and all EBM reviews--Cochrane DSR, ACP Journal Club, DARE, and CCTR (Jan 2006). The Physiotherapy Evidence Database (PEDro) was also searched using the keyword: eccentric.

REVIEW METHODS

The PEDro and van Tulder scales were employed to assess methodological quality. Levels of evidence were then obtained according to predefined thresholds: Strong--consistent findings among multiple high-quality RCTs. Moderate--consistent findings among multiple low-quality RCTs and/or clinically controlled trials (CCTs) and/or one high-quality RCT. Limited--one low-quality RCT and/or CCT. Conflicting--inconsistent findings among multiple trials (RCTs and/or CCTs). No evidence-no RCTs or CCTs.

RESULTS

Twenty relevant studies were sourced, 11 of which met the inclusion criteria. These included studies of Achilles tendinopathy (AT), patella tendinopathy (PT) and tendinopathy of the common wrist extensor tendon of the lateral elbow (LET). Limited levels of evidence exist to suggest that EE has a positive effect on clinical outcomes such as pain, function and patient satisfaction/return to work when compared to various control interventions such as concentric exercise (CE), stretching, splinting, frictions and ultrasound. Levels of evidence were found to be variable across the tendinopathies investigated.

CONCLUSIONS

This review demonstrates the dearth of high-quality research in support of the clinical effectiveness of EE over other treatments in the management of tendinopathies. Further adequately powered studies that include appropriate randomisation procedures, standardised outcome measures and long-term follow-up are required.

Eccentric overload training in patients with chronic Achilles tendinopathy: a systematic review

BACKGROUND

Eccentric overload training seems to be a promising conservative intervention in patients with chronic Achilles tendinopathy. The efficacy of eccentric overload training on the outcome measures of pain and physical functioning are not exactly clear.

STUDY DESIGN

Systematic review of the literature.

METHODS

Electronic databases were searched for randomised clinical trials concerning eccentric overload training in patients with chronic Achilles tendinopathy. The Delphi list was used to assess the methodological quality of the studies.

RESULTS

Nine clinical trials were included. Only one study had sufficient methodological quality. The included trials showed an improvement in pain after eccentric overload training. Because of the methodological shortcomings of the trials, no definite conclusion can be drawn concerning the effects of eccentric overload training in patients with chronic Achilles tendinopathy.

CONCLUSION

The effects of eccentric exercise training in patients with chronic Achilles tendinopathy on pain are promising; however, the magnitude of the effects cannot be determined. Large, methodologically sound studies from multiple sites in which functional outcome measures are included are warranted.

Chronic lateral epicondylitis: comparative effectiveness of a home exercise program including stretching alone versus stretching supplemented with eccentric or concentric strengthening

The objective of this study was to evaluate the effectiveness of eccentric strengthening. Ninety-four subjects (50 men) with chronic lateral epicondylitis were allocated randomly into three groups: stretching, concentric strengthening with stretching, and eccentric strengthening with stretching. Subjects performed an exercise program for six weeks. All three groups received instruction on icing, stretching, and avoidance of aggravating activities. The strengthening groups received instruction on isolated concentric and eccentric wrist extensor strengthening, respectively. At six weeks, significant gains were made in all three groups as assessed with pain-free grip strength, Patient-rated Forearm Evaluation Questionnaire, Disabilities of the Arm, Shoulder, and Hand questionnaire, Short Form 36, and visual analog pain scale. No significant differences in outcome measures were noted among the three groups. Although there were no significant differences in outcome among the groups, eccentric strengthening did not cause subjects to worsen. Further studies are needed to assess the unique effects of a more intense or longer eccentric strengthening program for patients with lateral epicondylitis.

Paratendinopathy

Because most Achilles tendon injuries take place in sports and there has been a general increase in the popularity of sporting activities, the number and incidence of Achilles tendon overuse injuries have increased in the industrialized countries during the last few decades. The term "Achilles paratendinopathy" is used in clinical practice to describe activity-related Achilles pain combined with tenderness on palpation, providing that there is no suspicion of intratendinous pathology on the basis of patient history, clinical examination, or imaging examinations. This article discusses Achilles paratendinopathy.

Achilles tendon disorders: etiology and epidemiology

The Achilles tendon is the strongest tendon in the human body. Because most Achilles tendon injuries take place in sports and there has been a general increase in popularity of sporting activities, the number and incidence of the Achilles tendon overuse injuries and complete, spontaneous ruptures has increased in the industrialized countries during the last decades. The most common clinical diagnosis of Achilles overuse injuries is tendinopathy. The basic etiology of the Achilles tendinopathy is known to be multi-factorial. Although histopathologic studies have shown that ruptured Achilles tendons have clear degenerative changes before the rupture, many Achilles tendon ruptures take place suddenly without any preceding signs or symptoms.

Immediate Achilles tendon response after strength training evaluated by MRI

PURPOSE

To evaluate the tendon response after acute strength training in chronic Achilles tendinosis using magnetic resonance imaging (MRI).

METHODS

Twenty-two patients (44 Achilles tendons, 15 males, 8 patients with bilateral symptoms) with a median age of 45 yr (range 28-57 yr) were included in the study. In all patients, both Achilles tendons were examined with MRI before and immediately after a standardized training program. The most painful side underwent 6 sets and 15 repetitions of heavy-loaded eccentric training. The contralateral tendons underwent only concentric loading during the training program. The tendon volume and the intratendinous signal were evaluated and calculated by MRI using a seed-growing technique.

RESULTS

The immediate response of eccentric loading on the symptomatic tendons resulted in a 12% increase of the tendon volume, evident on T2-WI, from 7.8 +/- 2.0 to 8.8 +/- 2.7 cm3 (P < 0.001), and a 31% increase of the intratendinous signal evident on PD-WI, from 221 +/- 74 to 278 +/- 78 signal units (SU) (P < 0.001). The corresponding sequences on the contralateral concentrically loaded tendons showed an increase of 17% of tendon volume, from 6.1 +/- 1.5 to 7.0 +/- 1.6 cm3 (P < 0.001), and an increase of 27% of the intratendinous signal, from 170 +/- 55 to 211 +/-57 SU (P < 0.001). There was no significant difference of the mean of the increased tendon volume and the intratendinous signal between the eccentrically heavily loaded symptomatic tendons and the concentrically loaded contralateral tendons.

CONCLUSIONS

Both eccentric and concentric loading of the Achilles tendon resulted in increased total tendon volume and intratendinous signal. This increase may be explained by a higher water content and/or hyperemia in the Achilles tendon during and/or immediately after strength training of the gastrocnemius-soleus complex.

Topical glyceryl trinitrate for chronic Achilles tendinopathy

OBJECTIVE

To determine whether continuous application of topical glyceryl trinitrate decreases pain and symptoms in chronic noninsertional Achilles tendinopathy.

DESIGN

Randomized double-blind placebo-controlled study of 6-months' duration.

SETTING

Community and referral study at an Australian University Hospital.

PARTICIPANTS

Recruitment was through newspaper advertisements and private consulting rooms. Eligibility criteria were age >18 years, a history of insidious onset of Achilles tendon pain, a tender nodule localized to the region of the calcaneal insertion, and an ultrasound examination that excluded a tendon tear. Exclusion criteria were Achilles tendinopathy of <3 months' duration, a previous operation on, or dislocation of, the affected ankle or leg, distal neurologic signs, a local corticosteroid injection in the previous 3 months, and current pregnancy. The 65 participants (84 affected tendons; 62% men) had a median age of 49 years (range, 24-79 years), with a median duration of symptoms of 16 months (range, 4-147 months).

INTERVENTION

Participants were assigned an active transdermal patch (1/4 of a Nitro-Dur 5 [Schering-Plough] glyceryl trinitrate patch), which delivered 1.25 mg of glyceryl trinitrate over 24 hours, or a placebo patch. Patients were required to cut the patches into quarters and apply 1/d to the site of maximal tenderness for the 24-week duration of the study. All patients were also given 500-mg paracetamol tablets for use with headaches, and instructed in a rehabilitation program that comprised rest from aggravating activities, the use of heel-raise wedges, prolonged daily stretching of the gastrocnemius and soleus musculature, and an eccentric calf muscle-strengthening program.

MAIN OUTCOME MEASURES

At the baseline, 2, 6, 12, and 24-week examinations the patient completed a symptom assessment sheet to rate the severity of Achilles pain with activity, at rest, and at night (0 = no pain, 4 = very severe pain). The single assessor used the same scale to measure local tenderness; an 11-point scale for the patient to report pain after the single-leg 10-hop test; and also measured the ankle plantar flexor mean peak force and ankle plantar flexor work. Follow-up was 89% complete.

MAIN RESULTS

The groups did not differ in pain with activity, night pain, or local tenderness until the 12-week assessment when participants in the glyceryl trinitrate group reported less pain on each measure (mean scores, 0.9 vs. 1.6 [P = 0.02]; 0.2 vs. 0.7 [P = 0.04]; and 0.9 vs. 1.6 [P = 0.02], respectively). The difference was maintained at 24 weeks for pain with activity (mean scores, 0.4 vs. 1.0 [P = 0.03]). At 24 weeks the glyceryl trinitrate group reported less pain on the 10-hop test than the placebo group (mean scores, 0.5 vs. 1.6 [P = 0.005]). Although the intervention group showed a greater increase in plantar flexor mean total work at 24 weeks than the placebo group, the baseline scores were significantly different. The groups did not differ in pain at rest or in ankle plantar flexor peak force. Combining all the measures showed an estimated 14% (95% CI, 9%-19%) excess of asymptomatic tendons in the intervention group at 6 months. Reported main side effects were headaches (glyceryl trinitrate group, 53%; placebo group, 45%) and rashes (glyceryl trinitrate group, 16%%; placebo group, 12%).

CONCLUSION

A topical glyceryl trinitrate patch was more effective than placebo for reducing pain from chronic noninsertional Achilles tendonitis in the first 12 and 24 weeks of use.