Ultrasonographic investigation of the Achilles tendon in elite badminton players using color Doppler

Diagnostic Value of Superb Microvascular Imaging of the Rotator Cuff Interval for the Early Diagnosis of Frozen Shoulder

Purpose

To explore the early diagnostic value of superb microvascular imaging (SMI) features within the rotator cuff gap for frozen shoulder.

Patients and Methods

This prospective study enrolled patients with acute early-stage frozen shoulder seeking treatment at Zhabei Central Hospital in Jing'an District, Shanghai, between July 2021 and December 2022 were enrolled in this study. Healthy controls were collected in a 1:1 ratio from the same hospital's physical examination center. All participants underwent SMI and power Doppler ultrasound (PDUS) of the rotator cuff gap.

Results

The study included 79 patients with frozen shoulder and 77 healthy controls. Compared with the healthy control group, the patient group had a higher proportion of hypoechoic rotator cuff gap (81.0% vs 48.1%, P<0.001), a thicker coracohumeral ligament (2.60±1.01 vs 2.03±0.97, P<0.001), a thicker glenohumeral joint capsule (3.10±0.99 vs 2.46±1.17, P<0.001), and elevated blood grading using SMI (P<0.001) and PDUS (P=0.014). The highest area under the curve (AUC) was observed for SMI blood flow grading (AUC=0.824, 95% CI: 0.755-0.880, P<0.001), resulting in 82% sensitivity and 77% specificity when using a cutoff of 1. SMI blood flow grading was associated with external rotation <30° (P=0.007) and abduction <30° (P=0.013) but not with internal rotation <30° (P=0.630) or flexion <30° (P=0.562).

Conclusion

The grading of SMI blood flow may emerge as a valuable predictive indicator for the early stages of frozen shoulder. This simple ultrasound technique holds the potential to enhance the diagnostic process, enabling early initiation of treatment and potentially improving patient outcomes.

Adjusted Landing Technique Reduces the Load on the Achilles Tendon in Badminton Players

Achilles tendon (AT) rupture is common among recreational male badminton players. We hypothesize that a landing technique following forehand jump strokes with the landing foot in a neutral position often performed by recreational players and occasionally by elite players may expose the AT to higher loads than a scissor kick jump (SKJ) technique with the leg/foot externally rotated. The study aimed to investigate if recreational players could reduce the load in the AT when adopting the SKJ technique compared to their habitual landing technique with the foot in a neutral position and secondarily to compare the AT force between recreational players and elite players. Ten recreational male players performed simulated jump strokes in a biomechanical laboratory using both their original technique and the SKJ technique traditionally used by elite players. For comparison reasons ten elite players performed SKJs. Landing kinematics and AT forces were captured and calculated using 3D movement analysis. The landing leg was more externally rotated in the recreational players' adjusted technique (78 ± 10 degrees, p < 0.001) compared to 22 ± 21 degrees in recreational players' original technique. The peak AT force of the recreational players was significantly higher for the original technique compared to the adjusted technique (68 ± 19 N/kg vs. 50 ± 14 N/kg, p = 0.005). Additionally, the peak AT forces observed during the recreational players' original technique was higher, though not significantly, than those observed for elite players (55 ± 11 N/kg, p = 0.017). / = 0.016 due to a Bonferroni correction. These findings indicate that recreational badminton players that normally land with the foot in a neutral position, may reduce their AT load by 25% when adopting the SKJ technique of elite players and land with the leg/foot in an externally rotated position.

Training and injuries among world elite junior badminton players - Identifying the problems

BACKGROUND

The game of badminton has evolved since the early injury epidemiology studies. Since there is no published literature on injuries in elite junior badminton players from an international cohort, this study provides an updated reference of injuries in this population to inform future injury prevention strategies. The objective of this study was to report injury prevalence and training hours in elite junior badminton players participating at the World Junior Championships in 2018.

METHODS

A questionnaire was used to collect data and was available in English, French, Spanish, Korean, Japanese or Chinese. It was designed to collect information including basic demographics, hours of training and competition, number of tournaments per year, current and previous injuries characterized by anatomical region, diagnosis, treatment and injury duration. The questions were focused on previous significant injuries lasting a minimum of 30 days and current musculoskeletal symptoms.

RESULTS

One hundred and sixty-four of 436 players with a mean age of 17.1 years (SD ± 0.8) filled in the questionnaire. Participants represented North and South America, Europe, Asia, Africa and The Pacific's including the top 10 performing nations, providing a good overall representation of tournament participants. A total of 104 significant injuries (median duration of 90 days) with disruption of full training or competition capacity were reported. Seventy-eight (48%) players reported one or more significant injury. The most common location of significant injury was in the knee, ankle and lower back. Eleven injuries were reported as stress fractures. In 35 cases a player felt lasting limitation from a significant injury and in 37 cases a player felt lasting pain.

CONCLUSION

Previously in their career almost 50% of the players had sustained a significant injury with a median duration of 90 days. The lower extremities and the lower back were the predominant injured regions. In one third of the injuries a player had lasting limitations or pain. Stress fractures may be a serious underestimated problem in badminton.

Ultrasound Color Doppler Measures Neovascularization in Achilles Tendinopathy: Review

Purpose: Color Doppler ultrasonography (CD) has been used to employ in Achilles tendinopathy, there is a need to measure neovascularization in Achilles tendinopathy to reach a consensus for CD application. The object of this systematic retrospect is to summarize the literature regarding whether is a relationship between the neovascularization and Achilles tendinopathy by CD detecting. Method: The databases search of PubMed, Scopus, and Embase extracted 543 articles for title and abstract review. After deleting duplicate papers and evaluating which one meets the inclusion criteria, a total of 8 articles were selected. Results and conclusion: Differentiate a physiological and pathological color Doppler flow in Achilles tendon is important to further clinically diagnose, since neovascularization in tissue structure can be influenced by variation reasons. The standardized tenoangiography protocol be supposed to develop when assessment asymptomatic or symptomatic tendons.

Intraindividual Doppler Flow Response to Exercise Differs Between Symptomatic and Asymptomatic Achilles Tendons

Objective

This study investigated intraindividual differences of intratendinous blood flow (IBF) in response to running exercise in participants with Achilles tendinopathy.

Design

This is a cross-sectional study.

Setting

The study was conducted at the University Outpatient Clinic.

Participants

Sonographic detectable intratendinous blood flow was examined in symptomatic and contralateral asymptomatic Achilles tendons of 19 participants (42 ± 13 years, 178 ± 10 cm, 76 ± 12 kg, VISA-A 75 ± 16) with clinically diagnosed unilateral Achilles tendinopathy and sonographic evident tendinosis.

Intervention

IBF was assessed using Doppler ultrasound “Advanced Dynamic Flow” before (Upre) and 5, 30, 60, and 120 min (U5–U120) after a standardized submaximal constant load run.

Main Outcome Measure

IBF was quantified by counting the number (n) of vessels in each tendon.

Results

At Upre, IBF was higher in symptomatic compared with asymptomatic tendons [mean 6.3 (95% CI: 2.8–9.9) and 1.7 (0.4–2.9), p < 0.01]. Overall, 63% of symptomatic and 47% of asymptomatic Achilles tendons responded to exercise, whereas 16 and 11% showed persisting IBF and 21 and 42% remained avascular throughout the investigation. At U5, IBF increased in both symptomatic and asymptomatic tendons [difference to baseline: 2.4 (0.3–4.5) and 0.9 (0.5–1.4), p = 0.05]. At U30 to U120, IBF was still increased in symptomatic but not in asymptomatic tendons [mean difference to baseline: 1.9 (0.8–2.9) and 0.1 (-0.9 to 1.2), p < 0.01].

Conclusion

Irrespective of pathology, 47–63% of Achilles tendons responded to exercise with an immediate acute physiological IBF increase by an average of one to two vessels (“responders”). A higher amount of baseline IBF (approximately five vessels) and a prolonged exercise-induced IBF response found in symptomatic ATs indicate a pain-associated altered intratendinous “neovascularization.”

Biomechanical stress in the context of competitive sports training triggers enthesitis

OBJECTIVE

To evaluate the influence of mechanical stress on the development of immediate enthesitis.

METHODS

The BEAT study is an interventional study that assessed entheses in competitive badminton players before and immediately after a 60-min intensive training session. Power Doppler (PD) signal and Gray scale (GS) changes were assessed in the insertion sites of both Achilles tendon, patellar tendons, and lateral humeral epicondyles and quantified using a validated scoring system.

RESULTS

Thirty-two badminton players were included. One hundred ninety-two entheseal sites were examined twice. The respective empirical total scores for PD examination were 0.1 (0.3) before and 0.5 (0.9) after training. Mean total GS scores were 2.9 (2.5) and 3.1 (2.5) before and after training, respectively. The mean total PD score difference of 0.4 between pre- and post-training was significant (p = 0.0014), whereas no significant difference for the mean total GS score was observed. Overall, seven participants (22%) showed an increased empirical total PD score. A mixed effects model showed a significant increase of PD scores after training, with a mean increase per site of 0.06 (95% CI 0.01 to 0.12, p = 0.017).

CONCLUSIONS

Mechanical stress leads to rapid inflammatory responses in the entheseal structures of humans. These data support the concept of mechanoinflammation in diseases associated with enthesitis.

Doppler Flow Response Following Running Exercise Differs Between Healthy and Tendinopathic Achilles Tendons

Background

The relationship between exercise-induced intratendinous blood flow (IBF) and tendon pathology or training exposure is unclear.

Objective

This study investigates the acute effect of running exercise on sonographic detectable IBF in healthy and tendinopathic Achilles tendons (ATs) of runners and recreational participants.

Methods

48 participants (43 ± 13 years, 176 ± 9 cm, 75 ± 11 kg) performed a standardized submaximal 30-min constant load treadmill run with Doppler ultrasound “Advanced dynamic flow” examinations before (U_pre) and 5, 30, 60, and 120 min (U₅-U₁₂₀) afterward. Included were runners (>30 km/week) and recreational participants (<10 km/week) with healthy (H_run, n = 10; H_rec, n = 15) or tendinopathic (T_run, n = 13; T_rec, n = 10) ATs. IBF was assessed by counting number [n] of intratendinous vessels. IBF data are presented descriptively (%, median [minimum to maximum range] for baseline-IBF and IBF-difference post-exercise). Statistical differences for group and time point IBF and IBF changes were analyzed with Friedman and Kruskal-Wallis ANOVA (α = 0.05).

Results

At baseline, IBF was detected in 40% (3 [1–6]) of H_run, in 53% (4 [1–5]) of H_rec, in 85% (3 [1–25]) of T_run, and 70% (10 [2–30]) of T_rec. At U₅ IBF responded to exercise in 30% (3 [−1–9]) of H_run, in 53% (4 [−2–6]) of H_rec, in 70% (4 [−10–10]) of T_run, and in 80% (5 [1–10]) of T_rec. While IBF in 80% of healthy responding ATs returned to baseline at U₃₀, IBF remained elevated until U₁₂₀ in 60% of tendinopathic ATs. Within groups, IBF changes from U_pre-U₁₂₀ were significant for H_rec (p < 0.01), T_run (p = 0.05), and T_rec (p < 0.01). Between groups, IBF changes in consecutive examinations were not significantly different (p > 0.05) but IBF-level was significantly higher at all measurement time points in tendinopathic versus healthy ATs (p < 0.05).

Conclusion

Irrespective of training status and tendon pathology, running leads to an immediate increase of IBF in responding tendons. This increase occurs shortly in healthy and prolonged in tendinopathic ATs. Training exposure does not alter IBF occurrence, but IBF level is elevated in tendon pathology. While an immediate exercise-induced IBF increase is a physiological response, prolonged IBF is considered a pathological finding associated with Achilles tendinopathy.

Biomechanics of lower limb in badminton lunge: a systematic scoping review

Background

Badminton is a popular sport activity in both recreational and elite levels. A lot of biomechanical studies have investigated badminton lunge, since good lunge performance may increase the chances to win the game. This review summarized the current trends, research methods, and parameters-of-interest concerning lower-extremity biomechanics in badminton lunges.

Methodology

Databases including Web of Science, Cochrane Library, Scopus, and PubMed were searched from the oldest available date to September 2020. Two independent authors screened all the articles and 20 articles were eligible for further review. The reviewed articles compared the differences among playing levels, footwear designs, and lunge directions/variations, using parameters including ground reaction forces, plantar pressure distribution, kinematics, and kinetics.

Results

Elite badminton players demonstrated higher impact attenuation capability, more aggressive knee and ankle strategy (higher mechanical moment), and higher medial plantar load than amateur players. Footwear modifications can influence comfort perception and movement mechanics, but it remains inconclusive regarding how these may link with lunging performance. Contradicting findings in kinematics is possibly due to the variations in lunge and instructions.

Conclusions

Playing levels and shoe designs have significant effects on biomechanics in badminton lunges. Future studies can consider to use an unanticipated testing protocol and realistic movement intensity. They can study the inter-limb coordination as well as the contributions and interactions of intrinsic and extrinsic factors to injury risk. Furthermore, current findings can stimulate further research studying whether some specific footwear materials with structural design could potentially compromise impact attenuation, proprioception, and performance.

Ultrasound Characterization of Patellar Tendon in Non-Elite Sport Players with Painful Patellar Tendinopathy: Absolute Values or Relative Ratios? A Pilot Study

Imaging findings in patellar tendinopathy are questioned. The aim of this pilot study was to characterize ultrasound measures, by calculating ultrasound ratio and neovascularization of the patellar tendon in non-elite sport players with unilateral painful patellar tendinopathy. Cross-sectional area (CSA), width, and thickness of the patellar tendon were assessed bilaterally in 20 non-elite sport-players with unilateral painful patellar tendinopathy and 20 asymptomatic controls by a blinded assessor. Ultrasound ratios were calculated to discriminate between symptomatic and asymptomatic knees. The Ohberg score was used for characterizing neovascularization. We found that non-elite sport players with patellar tendinopathy exhibited bilateral increases in CSA, width, and thickness of the patellar tendon compared to asymptomatic controls (Cohen d > 2). The ability of ultrasound ratios to discriminate between painful and non-painful patellar tendons was excellent (receiver operating characteristic, ROC > 0.9). The best diagnostic value (sensitivity: 100% and specificity: 95%) was observed when a width ratio ≥ 1.29 between the symptomatic and asymptomatic patellar tendon was used as a cut-off. Further, neovascularization was also observed in 70% of non-elite sport players with unilateral patellar tendinopathy. A greater CSA ratio was associated with more related-disability and higher tendon neovascularization. This study reported that non-elite sport players with painful unilateral patellar tendinopathy showed structural ultrasound changes in the patellar tendon when compared with asymptomatic controls. Ultrasound ratios were able to discriminate between symptomatic and asymptomatic knees. Current results suggest that ultrasound ratios could be a useful imaging outcome for identifying changes in the patellar tendon in sport players with unilateral patellar tendinopathy.

Effect of Platelet-Rich Plasma on Nonsurgically Treated Acute Achilles Tendon Ruptures: A Randomized, Double-Blinded Prospective Study

BACKGROUND

An acute Achilles tendon rupture (ATR) is a long-lasting and devastating injury. Possible biological augmentation to promote and strengthen tendon healing after an ATR would be desirable.

PURPOSE

To determine whether the application of a platelet-rich plasma (PRP) injection in nonsurgically treated ATRs may promote healing and thereby improve functional outcomes.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

A total of 40 men (aged 18-60 years) with an ATR incurred within 72 hours were included, and 38 were followed for 12 months. All patients were treated with an orthosis with 3 wedges for 8 weeks; full weightbearing from day 1 was allowed, combined with either 4 PRP or 4 placebo injections (a few drops of saline, <0.5 mL, under the skin) 14 days apart. All patients received the same instructions on an exercise program starting from week 9. Outcomes included the self-reported Achilles tendon Total Rupture Score (ATRS) as well as heel-rise work, heel-rise height, tendon elongation, calf circumference, and ankle dorsiflexion range of motion.

RESULTS

The mean ATRS score improved in both groups at all time points (P < .001), but there was no difference between the groups at any time points (12 months: 90.1 points in PRP group and 88.8 points in placebo group). No differences in all functional outcomes at any time points were seen between the groups. At 12 months, the injured leg did not reach normal functional values compared with the uninjured leg.

CONCLUSION

The application of PRP in nonsurgically treated ATRs did not appear to show any superior clinical and functional improvement.

REGISTRATION

NCT02417922 (ClinicalTrials.gov identifier).

Mechanical and Material Tendon Properties in Patients With Proximal Patellar Tendinopathy

Introduction

The effect of chronic patellar tendinopathy on tissue function and integrity is currently unclear and underinvestigated. The aim of this cohort comparison was to examine morphological, material, and mechanical properties of the patellar tendon and to extend earlier findings by measuring the ability to store and return elastic energy in symptomatic tendons.

Methods

Seventeen patients with chronic (>3 months, VISA-P < 80), inferior pole patellar tendinopathy (24 ± 4 years; male = 12, female = 5) were carefully matched to controls (25 ± 3 years) for training status, pattern, and history of loading of the patellar tendon. Individual knee extension force, patellar tendon stiffness, stress, strain, Young’s modulus, hysteresis, and energy storage capacity, were obtained with combined dynamometry, ultrasonography, magnetic resonance imaging, and electromyography.

Results

Anthropometric parameters did not differ between groups. VISA-P scores ranged from 28 to 78 points, and symptoms had lasted from 10 to 120 months before testing. Tendon proximal cross-sectional area was 61% larger in the patellar tendinopathy group than in the control group. There were no differences between groups in maximal voluntary isometric knee extension torque (p = 0.216; d < −0.31) nor in tensile tendon force produced during isometric ramp contractions (p = 0.185; d < −0.34). Similarly, tendon strain (p = 0.634; d < 0.12), hysteresis (p = 0.461; d < 0.18), and strain energy storage (p = 0.656; d < 0.36) did not differ between groups. However, patellar tendon stiffness (−19%; p = 0.007; d < −0.74), stress (−27%; p< 0.002; d < −0.90) and Young’s modulus (−32%; p = 0.001; d < −0.94) were significantly lower in tendinopathic patients compared to healthy controls.

Discussion

In this study, we observed lower stiffness in affected tendons. However, despite the substantial structural and histological changes occurring with tendinopathy, the tendon capacity to store and dissipate energy did not differ significantly.

Power Doppler to investigate superficial digital flexor tendinopathy in the horse

Background:

Recent advances in tendinopathy research have focused on tendon vascularization detected with Color Doppler (CD) ultrasound. The use of CD has also been described in horses in a study on chronic lesions of superficial digital flexor tendon and suspensory ligament.

Aim:

The aim of this study was to investigate the occurrence and distribution of power Doppler (PD) signal in horses with superficial digital flexor tendinopathy.

Methods:

Twenty-five horses with tendinopathy were included and 10 healthy horses with no lameness and no ultrasonographic abnormalities were used for comparison.

Results:

In all horses with tendinopathy, the PD signal was visible while normal tendons with no abnormalities in B-mode were PD signal-free.

Conclusion:

We can speculate that PD could provide essential information about the healing process than the grayscale ultrasound.

Patellar Tendon Strain Associates to Tendon Structural Abnormalities in Adolescent Athletes

High mechanical strain is thought to be one of the main factors for the risk of tendon injury, as it determines the mechanical demand placed upon the tendon by the working muscle. The present study investigates the association of tendon mechanical properties including force, stress and strain, and measures of tendon micromorphology and neovascularization, which are thought to be indicative of tendinopathy in an adolescent high-risk group for overuse injury. In 16 adolescent elite basketball athletes (14–15 years of age) we determined the mechanical properties of the patellar tendon by combining inverse dynamics with magnetic resonance and ultrasound imaging. Tendon micromorphology was determined based on a spatial frequency analysis of sagittal plane ultrasound images and neovascularization was quantified as color Doppler area. There was a significant inverse relationship between tendon strain and peak spatial frequency (PSF) in the proximal tendon region (r = −0.652, p = 0.006), indicating locally disorganized collagen fascicles in tendons that are subjected to high strain. No such associations were present at the distal tendon site and no significant correlations were observed between tendon force or stress and tendon PSF as well as between tendon loading and vascularity. Our results suggest that high levels of tendon strain might associate to a micromorphological deterioration of the collagenous network in the proximal patellar tendon, which is also the most frequent site affected by tendinopathy. Neovascularization of the tendon on the other hand seems not to be directly related to the magnitude of tendon loading and might be a physiological response to a high frequency of training in this group. Those findings have important implications for our understanding of the etiology of tendinopathy and for the development of diagnostical tools for the assessment of injury risk.

High volume injection with and without corticosteroid in chronic midportion achilles tendinopathy

BACKGROUND

High volume injection (HVI) shows promising results in the treatment of chronic midportion Achilles tendinopathy (AT). HVI consists of a large volume of saline with a small amount of corticosteroid and local anesthetic.

OBJECTIVE

To determine the effect of corticosteroid in HVI in AT.

METHODS

A total of 28 men (18-59 years) with chronic (>3 months) AT were included in a double-blinded RCT and followed for 24 weeks. All performed eccentric training and randomized to either (a) HVI injection with corticosteroid or (b) HVI injection without corticosteroid. Outcomes included self-reported function (VISA-A score) and pain (VAS score) and ultrasound imaging (tendon thickness, Doppler flow).

RESULTS

VISA-A and VAS score improved in both groups at all time-points (P < 0.05). VISA-A improvement was significantly greater in HVI with corticosteroid (mean ± SEM; 6-weeks = 31 ± 3 points; 12-weeks = 32 ± 5 points) vs HVI without corticosteroid (6 weeks = 14 ± 3; 12-weeks = 17 ± 3) at 6 and 12 weeks (P < 0.05), but not at 24 weeks. Decrease in VAS scores was significantly greater in HVI with corticosteroid (6 weeks = 55 ± 3 mm; 12 weeks = 53 ± 5 mm) vs HVI without corticosteroid (6 weeks = 16 ± 3 mm; 12 weeks = 25 ± 5 mm) at 6 and 12 weeks (P < 0.05) but not at 24 weeks. Tendon thickness decreased significantly in both groups at all time-points (P < 0.05), but more in the HVI with corticosteroid vs HVI without corticosteroid at 6 and 12 weeks (P < 0.05) but not at 24 weeks.

CONCLUSION

High volume injection with or without corticosteroid in combination with eccentric training seems effective in AT. HVI with corticosteroid showed a better short-term improvement than HVI without corticosteroid indicating a short-term effect of corticosteroid in HVI treatment of AT.

Reliability of Evaluating Achilles Tendon Vascularization Assessed With Doppler Ultrasound Advanced Dynamic Flow

OBJECTIVES

The reliability of quantifying intratendinous vascularization by high-sensitivity Doppler ultrasound advanced dynamic flow has not been examined yet. Therefore, this study aimed to investigate the intraobserver and interobserver reliability of evaluating Achilles tendon vascularization by advanced dynamic flow using established scoring systems.

METHODS

Three investigators evaluated vascularization in 67 recordings in a test-retest design, applying the Ohberg score, a modified Ohberg score, and a counting score. Intraobserver and interobserver agreement for the Ohberg score and modified Ohberg score was analyzed by the Cohen κ and Fleiss κ coefficients (absolute), Kendall τ b coefficient, and Kendall coefficient of concordance (W; relative). The reliability of the counting score was analyzed by intraclass correlation coefficients (ICC) 2.1 and 3.1, the standard error of measurement (SEM), and Bland-Altman analysis (bias and limits of agreement [LoA]).

RESULTS

Intraobserver and interobserver agreement (absolute/relative) ranged from 0.61 to 0.87/0.87 to 0.95 and 0.11 to 0.66/0.76 to 0.89 for the Ohberg score and from 0.81 to 0.87/0.92 to 0.95 and 0.64 to 0.80/0.88 to 0.93 for the modified Ohberg score, respectively. The counting score revealed an intraobserver ICC of 0.94 to 0.97 (SEM, 1.0-1.5; bias, -1; and LoA, 3-4 vessels). The interobserver ICC for the counting score ranged from 0.91 to 0.98 (SEM, 1.0-1.9; bias, 0; and LoA, 3-5 vessels).

CONCLUSIONS

The modified Ohberg score and counting score showed excellent reliability and seem convenient for research and clinical practice. The Ohberg score revealed decent intraobserver but unexpected low interobserver reliability and therefore cannot be recommended.

Barriers and facilitators of physical activity in knee and hip osteoarthritis: a systematic review of qualitative evidence

Physical activity (PA), including engagement in structured exercise, has a key role in the management of hip and knee osteoarthritis (OA). However, maintaining a physically active lifestyle is a challenge for people with OA. PA determinants in this population need to be understood better so that they can be optimised by public health or healthcare interventions and social policy changes.

OBJECTIVES

The primary aim of this study is to conduct a systematic review of the existing qualitative evidence on barriers and facilitators of PA for patients with hip or knee OA. Secondary objective is to explore differences in barriers and facilitators between (1) lifestyle PA and exercise and (2) PA uptake and maintenance.

METHODS

Medline, Embase, Web of Science, Cumulative Index to Nursing and Allied Health Literature, SPORTDiscus, Scopus, Grey literature and qualitative journals were searched. Critical Appraisal Skills Programme-Qualitative checklist and Lincoln and Guba's criteria were used for quality appraisal. Thematic synthesis was applied.

FINDINGS

Ten studies were included, seven focusing on exercise regimes, three on overall PA. The findings showed a good fit with the biopsychosocial model of health. Aiming at symptom relief and mobility, positive exercise experiences and beliefs, knowledge, a 'keep going' attitude, adjusting and prioritising PA, having healthcare professionals' and social support emerged as PA facilitators. Pain and physical limitations; non-positive PA experiences, beliefs and information; OA-related distress; a resigned attitude; lack of motivation, behavioural regulation, professional support and negative social comparison with coexercisers were PA barriers. All themes were supported by high and medium quality studies. Paucity of data did not allow for the secondary objectives to be explored.

CONCLUSION

Our findings reveal a complex interplay among physical, personal including psychological and social-environmental factors corresponding to the facilitation and hindrance of PA, particularly exercise, engagement. Further research on the efficacy of individualised patient education, psychological interventions or social policy change to promote exercise engagement and lifestyle PA in individuals with lower limb OA is required.

TRIAL REGISTRATION NUMBER

CRD42016030024.

Effects of anti-inflammatory (NSAID) treatment on human tendinopathic tissue

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat tendinopathy, but evidence for this treatment is lacking, and little is known regarding effects of NSAIDs on human tendinopathic tendon. This study investigated the effects of NSAID treatment (ibuprofen) on human tendinopathic tendon, with changes in gene expression as the primary outcome, and tendon pain, function, and blood flow as secondary outcomes. Twenty-six adults (16 men, 10 women), diagnosed with chronic Achilles tendinopathy, were randomized to 1-wk treatment with ibuprofen (600 mg ×3/day) (n = 13) or placebo (n = 13) (double-blinded). Ibuprofen content in blood, visual analog scale score for tendon pain at rest and activity, Victorian Institute of Sports Assessment-Achilles (VISA-A) scores for tendon function, tendon thickness (with ultrasonography), and color Doppler were measured before and 1 h after treatment. After the last posttreatment test, a full-width tendon biopsy was taken from the affected area. Real-time-RT-PCR was used to assess expression of collagen I, collagen III, transforming growth factor (TGF-β) isoforms, cyclooxygenase-2 (COX-2), angiopoietin-like 4 (ANGPTL4), and cyclic AMP-dependent transcription factor (ATF3) in tendon tissue. Expression of collagens and TGF-β isoforms showed relatively low variation and was unaffected by ibuprofen treatment. Further, no changes were seen in tendon thickness or VISA-A score. The placebo treatment reduced the color Doppler (in tendon plus surrounding tissue) compared with the ibuprofen group and also increased the perception of pain at rest. In conclusion, there was no indication that short-term ibuprofen treatment affects gene expression in human chronic tendinopathic tendon or leads to any clear changes in tendon pain or function.NEW & NOTEWORTHY Nonsteroidal anti-inflammatory drugs are widely used in the treatment of tendinopathy, but little is known of the effects of these drugs on tendon tissue. We find that 1 wk of ibuprofen treatment has no effect on gene expression of collagen and related growth factors in adult human tendinopathic tendon in vivo (in spite of relatively low levels of variation in gene expression), suggesting that tendinopathic cells are not responsive to ibuprofen.

Effect of High-Volume Injection, Platelet-Rich Plasma, and Sham Treatment in Chronic Midportion Achilles Tendinopathy: A Randomized Double-Blinded Prospective Study

BACKGROUND

Injection therapies are often considered alongside exercise for chronic midportion Achilles tendinopathy (AT), although evidence of their efficacy is sparse.

PURPOSE

To determine whether eccentric training in combination with high-volume injection (HVI) or platelet-rich plasma (PRP) injections improves outcomes in AT.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 60 men (age, 18-59 years) with chronic (>3 months) AT were included and followed for 6 months (n = 57). All participants performed eccentric training combined with either (1) one HVI (steroid, saline, and local anesthetic), (2) four PRP injections each 14 days apart, or (3) placebo (a few drops of saline under the skin). Randomization was stratified for age, function, and symptom severity (Victorian Institute of Sports Assessment-Achilles [VISA-A]). Outcomes included function and symptoms (VISA-A), self-reported tendon pain during activity (visual analog pain scale [VAS]), tendon thickness and intratendinous vascularity (ultrasonographic imaging and Doppler signal), and muscle function (heel-rise test). Outcomes were assessed at baseline and at 6, 12, and 24 weeks of follow-up.

RESULTS

VISA-A scores improved in all groups at all time points ( P < .05), with greater improvement in the HVI group (mean ± SEM, 6 weeks = 27 ± 3 points; 12 weeks = 29 ± 4 points) versus PRP (6 weeks = 14 ± 4; 12 weeks = 15 ± 3) and placebo (6 weeks = 10 ± 3; 12 weeks = 11 ± 3) at 6 and 12 weeks ( P < .01) and in the HVI (22 ± 5) and PRP (20 ± 5) groups versus placebo (9 ± 3) at 24 weeks ( P < .01). VAS scores improved in all groups at all time points ( P < .05), with greater decrease in HVI (6 weeks = 49 ± 4 mm; 12 weeks = 45 ± 6 mm; 24 weeks = 34 ± 6 mm) and PRP (6 weeks = 37 ± 7 mm; 12 weeks = 41 ± 7 mm; 24 weeks = 37 ± 6 mm) versus placebo (6 weeks = 23 ± 6 mm; 12 weeks = 30 ± 5 mm; 24 weeks = 18 ± 6 mm) at all time points ( P < .05) and in HVI versus PRP at 6 weeks ( P < .05). Tendon thickness showed a significant decrease only in HVI and PRP groups during the intervention, and this was greater in the HVI versus PRP and placebo groups at 6 and 12 weeks ( P < .05) and in the HVI and PRP groups versus the placebo group at 24 weeks ( P < .05). Muscle function improved in the entire cohort with no difference between the groups.

CONCLUSION

Treatment with HVI or PRP in combination with eccentric training in chronic AT seems more effective in reducing pain, improving activity level, and reducing tendon thickness and intratendinous vascularity than eccentric training alone. HVI may be more effective in improving outcomes of chronic AT than PRP in the short term. Registration: NCT02417987 ( ClinicalTrials.gov identifier).

Acute effect of running exercise on physiological Achilles tendon blood flow

Sonographically detectable intratendinous blood flow (IBF) is found in 50%-88% of Achilles tendinopathy patients as well as in up to 35% of asymptomatic Achilles tendons (AT). Although IBF is frequently associated with tendon pathology, it may also represent a physiological regulation, for example, due to increased blood flow in response to exercise. Therefore, this study aimed to investigate the acute effects of a standardized running exercise protocol on IBF assessed with Doppler ultrasound (DU) "Advanced dynamic flow" in healthy ATs. 10 recreationally active adults (5 f, 5 m; 29±3 years, 1.72±0.12 m, 68±16 kg, physical activity 206±145 minute/wk) with no history of AT pain and inconspicious tendon structure performed 3 treadmill running tasks on separate days (M1-3) with DU examinations directly before and 5, 30, 60, and 120 minutes after exercise. At M1, an incremental exercise test was used to determine the individual anaerobic threshold (IAT). At M2 and M3, participants performed 30- minute submaximal constant load tests (CL₁ /CL₂ ) with an intensity 5% below IAT. IBF in each tendon was quantified by counting the number of vessels. IBF increased in five ATs from no vessels at baseline to one to four vessels solely detectable 5 minutes after CL₁ or CL₂ . One AT had persisting IBF (three vessels) throughout all examinations. Fourteen ATs revealed no IBF at all. Prolonged running led to a physiological, temporary appearance of IBF in 25% of asymptomatic ATs. To avoid exercise-induced IBF in clinical practice, DU examinations should be performed after 30 minutes of rest.

[Tendinopathies of the foot and ankle : Evidence for the origin, diagnostics and therapy]

Tendinopathies of the foot and ankle result in substantial impairment of the mobility of patients and have a high clinical significance. Knowledge of the origin of these diseases has been accumulated over decades from the multitude of intrinsic and extrinsic triggering factors based on biomechanical considerations with an evidence-based medicine (EBM) level 5. A high correlation between tendinopathy and hypervascularization of the Achilles tendon was found in a double-blind randomized prospective study using Doppler ultrasound (EBM level 1) but these results were not reproducible; therefore, the importance of these findings is unclear. Inspection and clinical examination supplemented by ultrasound and magnetic resonance imaging (MRI) are essential to achieve the correct diagnosis. The varying extent of load-dependent irritation of tendons and the surrounding tissues and the individual variation in experience of investigators mean that the results of clinical examinations are difficult to collate or not reproducible and cannot be investigated in studies. The expression of the varying results is difficult to assess even by the use of sonography and magnetic resonance imaging (MRI). Conservative treatment of tendinopathy is based on medical experience (EBM level 5). The effectiveness of physiotherapeutic eccentric loading and extracorporal shock wave treatment (ESWT) for Achilles tendinopathy was demonstrated in several case control studies and series (EBM level 3). Due to the high rate of healing with physiotherapy, surgery should only be performed following a minimum of 6-12 weeks of unsuccessful conservative treatment, because formation of scar tissue on the foot can result in permanent complaints (EBM level 4).

Is Sonographic Assessment of Intratendinous Blood Flow in Achilles Tendinopathy Patients Reliable?: Consistency of Doppler Ultrasound Modes and Intra- and Inter-observer Reliability

PURPOSE

The purpose of this study was to investigate the consistency between different Doppler ultrasound (DU) modes as well as the intra- and inter-observer reliability of investigators with different experience level in assessing intratendinous blood flow (IBF) in Achilles tendinopathy patients.

MATERIAL AND METHODS

18 participants (36 Achilles tendons, AT) with Achilles tendinopathy (24 AT) were examined with power Doppler ultrasound (PDU), colour Doppler ultrasound (CDU) and "Advanced Dynamic Flow" (ADF) (Toshiba Xario SSA-660 A; 14MHz transducer) by 2 investigators (experienced, EI; inexperienced, II) in a test-retest design (M1/M2). A modified Öhberg score was used to quantify IBF. Data was analysed descriptively (absolute and relative). Consistency of the 3 modes was presented by Kendall's Coefficient of Concordance (Kendall's W). Intra- and inter-observer reliability were calculated by use of Kendall's tau b correlation coefficient.

RESULTS

IBF was detected in 79-92% of symptomatic AT and in 33-50% of contralateral asymptomatic AT. Comparing the 3 modes, Kendall's W ranged from 0.97-0.98. Analysis of intra-observer reliability resulted in Kendall's tau 0.90-0.92 for EI and 0.84-0.87 for II. Inter-observer reliability resulted in Kendall's tau 0.64-0.69 in M1 and 0.68-0.70 in M2.

CONCLUSION

The very good consistency between PDU, CDU and ADF indicates a comparable applicability for assessing IBF in ATs. Intra-observer reliability was high for both investigators, independent of experience. The moderate inter-observer reliability reflects the challenge in sonographic detection of intratendinous blood flow (IBF) amount.

Tendinopathy: Is Imaging Telling Us the Entire Story?

Synopsis Tendinopathy is frequently associated with structural disorganization within the tendon. As such, the clinical use of ultrasound and magnetic resonance imaging for tendinopathy has been the focus of numerous academic studies and clinical discussions. However, similar to other musculoskeletal conditions (osteoarthritis and intervertebral disc degeneration), there is no direct link between tendon structural disorganization and clinical symptoms, with findings on imaging potentially creating a confusing clinical picture. While imaging shows the presence and extent of structural changes within the tendon, the clinical interpretation of the images requires context in regard to the features of pain and the aggravating loads. This review will critically evaluate studies that have investigated the accuracy and sensitivity of imaging in the detection of clinical tendinopathy and the methodological issues associated with these studies (subject selection, lack of a robust gold standard, reliance on subjective measures). The advent of new imaging modalities allowing for the quantification of tendon structure or mechanical properties has allowed new critical insight into tendon pathology. A strength of these novel modalities is the ability to quantify properties of the tendon. Research utilizing ultrasound tissue characterization and sonoelastography will be discussed. This narrative review will also attempt to synthesize current research on whether imaging can predict the onset of pain or clinical outcome, the role of monitoring tendon structure during rehabilitation (ie, does tendon structure need to improve to get a positive clinical outcome?), and future directions for research, and to propose the clinical role of imaging in tendinopathy. J Orthop Sports Phys Ther 2015;45(11):842-852. Epub 21 Sep 2015. doi:10.2519/jospt.2015.5880.

Characteristics of Plantar Loads in Maximum Forward Lunge Tasks in Badminton

Background

Badminton players often perform powerful and long-distance lunges during such competitive matches. The objective of this study is to compare the plantar loads of three one-step maximum forward lunges in badminton.

Methods

Fifteen right-handed male badminton players participated in the study. Each participant performed five successful maximum lunges at three directions. For each direction, the participant wore three different shoe brands. Plantar loading, including peak pressure, maximum force, and contact area, was measured by using an insole pressure measurement system. Two-way ANOVA with repeated measures was employed to determine the effects of the different lunge directions and different shoes, as well as the interaction of these two variables, on the measurements.

Results

The maximum force (MF) on the lateral midfoot was lower when performing left-forward lunges than when performing front-forward lunges (p = 0.006, 95% CI = −2.88 to −0.04%BW). The MF and peak pressures (PP) on the great toe region were lower for the front-forward lunge than for the right-forward lunge (MF, p = 0.047, 95% CI = −3.62 to −0.02%BW; PP, p = 0.048, 95% CI = −37.63 to −0.16 KPa) and left-forward lunge (MF, p = 0.015, 95% CI = −4.39 to −0.38%BW; PP, p = 0.008, 95% CI = −47.76 to −5.91 KPa).

Conclusions

These findings indicate that compared with the front-forward lunge, left and right maximum forward lunges induce greater plantar loads on the great toe region of the dominant leg of badminton players. The differences in the plantar loads of the different lunge directions may be potential risks for injuries to the lower extremities of badminton players.

Prevalence of morphological and mechanical stiffness alterations of mid Achilles tendons in asymptomatic marathon runners before and after a competition

OBJECTIVE

To determine the prevalence of morphological and mechanical stiffness alterations at the mid Achilles tendon in asymptomatic marathon runners before and after a competition. To assess the relationship between pre-existing Achilles tendon alterations and pain after running.

MATERIALS AND METHODS

All marathon runners from a local running club who were participating in the Melbourne Marathon 2013 (full marathon category) were invited for conventional ultrasound and sonoelastography 1 week leading up to the marathon and again within 3 days post-marathon. Another group of active, healthy individuals not involved in running activities were recruited as controls. Intratendinous morphological (tendon thickness, hypoechogenicities), Doppler as well as stiffness properties of the Achilles were recorded. Achilles tendon pain was evaluated using the visual analogue scale (VAS) and Victorian Institute of Sports Assessment-Achilles (VISA-A).

RESULTS

Twenty-one asymptomatic runners (42 Achilles tendons) and 20 healthy controls (40 Achilles tendons) were examined. On the pre-marathon evaluation, runners showed significantly more morphological changes on B-mode ultrasound compared to the controls (p < 0.001). Marathon running induced a significant reduction in tendon stiffness (p = 0.049) and an increase in Doppler signals (p = 0.036). Four runners (4/21, 19%) reported Achilles tendon pain after the race [VAS 4.0 (±1.9), VISA 74.2 (±10.1)]. Reduced tendon stiffness at baseline was associated with post-marathon Achilles tendon pain (p = 0.016).

CONCLUSION

Marathon runners demonstrate a higher prevalence of morphological alterations compared to non-runners. Marathon running caused a significant change in Achilles tendon stiffness and Doppler signals. Pre-existing soft Achilles tendon properties on sonoelastography may be a predisposing risk for development of symptoms post-running.

Effect of autologous adipose tissue-derived mesenchymal stem cells on neovascularization of artificial equine tendon lesions

AIMS

To investigate whether autologous adipose tissue-derived mesenchymal stem cells (AT-MSCs) treatment of tendon lesions increases neovascularization during tendon healing.

MATERIALS & METHODS

A standardized surgical model was used to create lesions in both front limb superficial digital flexor tendons (SDFTs) of nine horses. Either AT-MSCs or control substance was injected intralesionally 2 weeks post-surgery. Color Doppler ultrasonography of SDFTs was performed at regular intervals. Horses were euthanized 22 weeks post-treatment and SDFTs were harvested for histology.

RESULTS

The color Doppler ultrasonography signal was significantly more extensive at 2 weeks post-treatment and the number of vessels counted on histologic slides was significantly higher at 22 weeks post-treatment in AT-MSC-treated SDFTs.

CONCLUSION

Our findings indicate that AT-MSC treatment has a beneficial effect on neovascularization of healing tendons.

A soft patellar tendon on ultrasound elastography is associated with pain and functional deficit in volleyball players

OBJECTIVES

To investigate the diagnostic performance of grey scale Ultrasound (US), power Doppler (PD) and US elastography for diagnosing painful patellar tendinopathy, and to establish their relationship with Victorian Institute of Sport Assessment-Patella (VISA-P) scores in a group of volleyball players with and without symptoms of patellar tendinopathy.

DESIGN

Cross-sectional study.

METHODS

Thirty-five volleyball players (70 patellar tendons) were recruited during a national university volleyball competition. Players were imaged with conventional US followed by elastography. The clinical findings of painful patellar tendons were used as the reference standard for diagnosing patellar tendinopathy. In addition, all participants completed the VISA-P questionnaires.

RESULTS

Of the 70 patellar tendons, 40 (57.1%) were clinically painful. The diagnostic accuracy of grey scale US, PD and elastography were 60%, 50%, 62.9%, respectively, with sensitivity/specificity of 72.5%/43.3%, 12.5%/100%, and 70%/53.3%, respectively. Combined US elastography and grey scale imaging achieved 82.5% sensitivity, 33.3% specificity and 61.4% accuracy while routine combination technique of PD and grey scale imaging revealed 72.5% sensitivity, 43.3% specificity and 60.0% accuracy. Tendons in players categorized as soft on elastography had statistically significantly greater AP thickness (p<0.001) and lower VISA-P scores (p=0.004) than those categorized as hard. There was no significant association between grey scale US abnormalities (hypoechogenicities and/or fusiform swelling) and VISA-P scores (p=0.098).

CONCLUSIONS

Soft tendon properties depicted by US elastography may be more related to patellar tendon symptoms compared to grey scale US abnormalities. The supplementation of US elastography to conventional US may enhance the sensitivity for diagnosing patellar tendinopathy in routine clinical practice.

Prevalence of Achilles and patellar tendinopathy and their association to intratendinous changes in adolescent athletes

Achilles (AT) and patellar tendons (PT) are commonly affected by tendinopathy in adult athletes but prevalence of symptoms and morphological changes in adolescents is unclear. The study aimed to determine prevalence of tendinopathy and intratendinous changes in ATs and PTs of adolescent athletes. A total of 760 adolescent athletes (13.0 ± 1.9 years; 160 ± 13 cm; 50 ± 14 kg) were examined. History, local clinical examination, and longitudinal Doppler ultrasound analysis for both ATs and PTs were performed including identification of intratendinous echoic changes and vascularization. Diagnosis of tendinopathy was complied clinically in case of positive history of tendon pain and tendon pain on palpation. Achilles tendinopathy was diagnosed in 1.8% and patellar tendinopathy in 5.8%. Vascularizations were visible in 3.0% of ATs and 11.4% of PTs, hypoechogenicities in 0.7% and 3.2% as well as hyperechogenicities in 0% and 0.3%, respectively. Vascularizations and hypoechogenicities were statistically significantly more often in males than in females (P ≤ 0.02). Subjects with patellar tendinopathy had higher prevalence of structural intratendinous changes than those without PT symptoms (P ≤ 0.001). In adolescent athletes, patellar tendinopathy is three times more frequent compared with Achilles tendinopathy. Longitudinal studies are necessary to investigate physiological or pathological origin of vascularizations and its predictive value in development of tendinopathy.

No inflammatory gene-expression response to acute exercise in human Achilles tendinopathy

Although histology data favour the view of a degenerative nature of tendinopathy, indirect support for inflammatory reactions to loading in affected tendons exists. The purpose of the present study was to elucidate whether inflammatory signalling responses after acute mechanical loading were more pronounced in tendinopathic versus healthy regions of human tendon and if treatment with non-steroidal anti-inflammatory medications (NSAID's) reduces this response. Twenty-seven tendinopathy patients (>6 months) were randomly assigned to a placebo (n = 14) or NSAID (Ibumetin NYCOMED GmbH Plant Oranienburg Germany (600 mg) × 3/day/1 week) group (n = 13) in a double-blinded-fashion. Tendon biopsies were taken from the painful and a healthy region of the same tendon 2 h after 1 h running. Gene-expression of several targets was analysed in the sampled Achilles tendon biopsies. The mRNA for TGF-β, collagen-I and collagen-III were significantly higher expressed, and decorin, CTGF, IL-6 and IL-10 were significantly lower expressed in the tendinopathic versus healthy tendon area. Only IL-10 was lower in expression in experiments with NSAID administration, while all other determined parameters were unaffected by NSAID. All ultrasonographic outcomes were unchanged in response to acute exercise and not influenced by NSAID. The signalling for collagen and TGF-beta was upregulated after acute loading in tendinopathic tendon. In contrast to the hypothesis, inflammatory signalling was not exaggerated in tendinopathic tendon 2 h after acute mechanical loading.

The volume of the neovascularity and its clinical implications in achilles tendinopathy

Thirty-seven pathologic Achilles tendons from 27 patients were investigated by a three-dimensional (3-D) power Doppler ultrasound system. Both the volume of the neovascularity (VON) and the volume of Achilles tendon (VOAT) were investigated. VON-VOAT index (VVI), as the normalization of the neovascularization, was accordingly calculated. Patient's clinical indications were assessed using the visual analog scale for pain (VAS) and Victorian Institute of Sport Assessment Achilles (VISA-A). Relationships between VAS and VON, VISA-A and VON, VAS and VOAT, VISA-A and VOAT, VAS and VVI, and VISA-A and VVI, were statistically analyzed. The vascular mapping within and surrounding the symptomatic Achilles tendons was investigated. 97.3% of the Achilles tendons were found to have neovascularization. In 55.6% of these Achilles, the neovascularity was associated with the location of thickening. The VAS was found to be positively correlated with the VON and the VVI, the VON was found to be independent from the VOAT.

Ultrasonographic Evaluation of Canine Supraspinatus Calcifying Tendinosis

Supraspinatus calcifying tendinosis is an uncommon finding in dogs. Although its radiographic appearance has been described previously, radiographs alone do not provide detailed information about the tendon parenchyma. Tendon ultrasonography has been widely applied for the diagnosis of human tendinosis, but it remains underused in dogs. This article reviews the ultrasonographic technique and variable appearance of canine supraspinatus calcifying tendinosis observed in 33 tendons. The ultrasonographic findings are described. The most common ultrasonographic finding was a hyperechoic area accompanied by distal acoustic shadowing. No relationship with bicipital tenosynovitis was found. A color Doppler examination was possible in only five of the tendons, revealing no blood flow in those tendons. There was evidence that the presence of a hypoechoic area surrounding the calcification was related to clinical signs of pain, suggesting an active inflammatory process. Ultrasonography was an excellent technique to evaluate lesions of the supraspinatus tendon and it revealed details not apparent on radiographs.

Imaging of tendons

Both magnetic resonance imaging (MRI) and sonography are well suited to tendon imaging. A normal tendon on MRI demonstrates low signal intensity and on sonography, an echogenic fibrillar pattern. MRI is considered the imaging gold standard, providing an anatomic overview and excellent soft tissue contrast. Sonography is a more rapidly performed examination; it has greater resolution than that of MRI; it allows dynamic evaluation of tendons and muscles; and it can guide percutaneous therapeutic procedures. Moreover, the advent of sonographic extended-field-of-view imaging allows the demonstration of the entire length of a tendon, matching MRI’s ability to display a large anatomic region. Sonography should best be considered a focused examination, concentrating on the area of pain and clinical suspicion of pathology, whereas MRI can provide a global assessment of the region of concern. Both modalities demonstrate high accuracy for abnormalities of various tendons. This article reviews normal tendon anatomy and its imaging appearance, as well as the imaging appearances of tendon degeneration and tear.

Immediate and short-term effects of exercise on tendon structure: biochemical, biomechanical and imaging responses

Introduction Tendons are metabolically active structures, and their biochemical, biomechanical and structural properties adapt to chronic exercise. However, abnormal adaptations may lead to the development of tendinopathy and pain. Acute and subacute adaptations might contribute to tendon pathology. Sources of data A systematic search of peer-reviewed articles was performed using a wide range of electronic databases. A total of 61 publications were selected. Areas of agreement Exercise induces acute responses in collagen turnover, blood flow, glucose, lactate and other inflammatory products (e.g. prostaglandins and interleukins). Mechanical properties are influenced by activity duration and intensity. Acute bouts of exercise affect tendon structure, with some of the changes resembling those reported in pathological tendons. Areas of controversy Given the variation in study designs, measured parameters and outcomes, it remains debatable how acute exercise influences overall tendon properties. There is discrepancy regarding which investigation modality and settings provide optimal assessment of each parameter. Growing points There is a need for greater homogeneity between study designs, including subject consortium and age, exercise protocols and time frames for parameter assessing. Areas timely for developing research Innovative methods, measuring each parameter simultaneously, would allow a greater understanding of how and when changes occur. This methodology is key to revealing pathological processes and pathways that alter tendon properties according to various activities. Optimal tendon properties differ between activities: more compliant tendons are beneficial for slow stretch shortening cycle (SSC) activities such as countermovement jumps, whereas stiffer tendons are considered beneficial for fast SSC movements such as sprinting.

Prognostic value of Achilles tendon Doppler sonography in asymptomatic runners

INTRODUCTION

Midportion Achilles tendinopathy (MPT) is a common problem in running athletes. Nevertheless, its etiology is not fully understood, and no valid prognostic criterion to predict the development of MPT could be identified to date. The purpose of the present study, therefore, was to evaluate whether power Doppler ultrasonography (PDU) is a suitable method to identify a predisposition to MPT in yet asymptomatic runners.

METHODS

At 23 major running events, 634 asymptomatic long-distance runners were tested for Achilles tendon thickness, vascularization, and structural abnormalities using a high-resolution PDU device (Toshiba Aplio SSA-770A/80, 12 MHz). In addition, their medical history and anthropometric data were documented. All subjects were contacted 6 and 12 months later and asked about any new symptoms. The collected anamnestic, anthropometric, and ultrasonographic data were subjected to regression analysis to determine their predictive value concerning the manifestation of midportion Achilles tendon complaints (P < 0.05).

RESULTS

The highest odds ratio (OR) for manifestation of MPT within 1 yr was found for intratendinous blood flow ("neovascularization," OR = 6.9, P < 0.001). An increased risk was also identified for subjects with a positive history of Achilles tendon complaints (OR = 3.8, P < 0.001). A third relevant parameter, just above the level of significance, was a spindle-shaped thickening of the tendon on PDU (Wald χ2 = 3.42).

CONCLUSIONS

PDU detection of intratendinous microvessels in the Achilles tendons of healthy runners seems to be a prognostically relevant factor concerning the manifestation of symptomatic MPT. This finding lays the foundation for an early identification of a predisposition to MPT as well as prophylactic intervention in as yet asymptomatic runners.

Associations between abnormal ultrasound color Doppler measures and tendon pain symptoms in badminton players during a season: a prospective cohort study

BACKGROUND

Color Doppler ultrasound is widely used to examine intratendinous flow in individuals with overuse tendon problems, but the association between color Doppler and pain is still unclear.

HYPOTHESIS

Intratendinous flow is present and associated with pain in badminton players, and intratendinous flow and pain increase during a badminton season.

STUDY DESIGN

Cohort study (prognosis); Level of evidence, 2.

METHODS

Ninety-five semiprofessional badminton players were included in the study at a tournament at the start of the badminton season. All players were interviewed regarding pain. The anterior knee tendons and Achilles tendons were studied. Each tendon was scored using a quantitative grading system (grades 0-5) and a qualitative scoring system (color fraction) using color Doppler ultrasound. Eight months later, 86 of the players (91%) were retested by the same investigators during an equivalent badminton tournament (including 1032 tendon regions; 86 players with 4 tendons each with 3 regions), thus forming the study group.

RESULTS

At the start of the season, 24 players (28%) experienced pain in 37 tendons (11%), and at the end of the season, 31 players (36%) experienced pain in 51 tendons (15%), which was a statistically significant increase (P = .0002). Abnormal flow was found in 230 tendon regions in 71 players (83%) at the start of the season compared with 78 tendon regions in 41 players (48%) at the follow-up. The decrease in abnormal flow was statistically significant (P < .0001). Of the 37 painful tendons at the start of the season, 25 had abnormal flow (68%). In contrast, 131 tendons (85%) with abnormal flow at the start of the season were pain free. At the end of the season, 18 of the 51 painful tendons (35%) had abnormal flow. Ninety-six of the 131 pain-free tendons (73%) with abnormal flow at the start of the season were normalized (no pain and normal flow) at the end of the season.

CONCLUSION

It was not possible to verify any association between intratendinous flow and pain at the start of the season or at the follow-up (end of the season). Intratendinous flow at the start of the season could not predict symptomatic outcome at the end of the season. The decrease in Doppler flow during the season might suggest that intratendinous flow could be part of a physiological adaptive response to loading and that intratendinous flow as previously believed is not always a sign of pathological changes.

A novel 3-D power Doppler ultrasound approach to the quantification of achilles tendon neovascularity

To investigate the amount of neovascularization in the symptomatic Achilles tendon, we developed a novel three-dimensional (3-D) power Doppler ultrasound scanning system to prospectively examine 10 patients with 12 symptomatic Achilles tendons, as well as 20 asymptomatic Achilles tendons as a control group. The mean volume of neovascularity (VON) in the whole Achilles tendon was calculated during the phase of the cardiac cycle displaying maximum vascularity and also during the phase of the cardiac cycle displaying the minimum. The mean VONs in the control group were found to be 0.41 mm(3) (maximum) and 0.02 mm(3) (minimum), respectively. The mean VONs in patients with painful Achilles tendon were 380 mm(3) (maximum) and 70.3 mm(3) (minimum), respectively. The initial results showed that the 3-D power Doppler ultrasound system could be used to measure the mean VON in controls and in patients with symptomatic Achilles tendinopathy. The results demonstrated a significantly greater VON in the maximum phase compared with the minimum phase as well as in the patient group compared with that in the control group. The system was therefore capable of defining the degree of vascularity in the Achilles tendon.

Evidence of accumulated stress in Achilles and anterior knee tendons in elite badminton players

Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler (CD) activity in both the Achilles and patella tendon after loading during high-level badminton matches. The Achilles tendon was subdivided into a mid-tendon, pre-insertional, and insertional region and the anterior knee tendons into a quadriceps-, patella- and tuberositas region. Intra-tendinous flow was measured using both a semi-quantitative grading system (CD grading) and a quantitative scoring system (CF) on colour Doppler. Intra-tendinous flow in the Achilles and anterior knee tendons was examined in fourteen single players before tournament and after 1st and 2nd match, respectively on both the dominant and non-dominant side. All players had abnormal intra-tendinous flow (Colour Doppler ≥ grade 2) in at least one tendon in at least one scan during the tournament. At baseline, only two of the 14 players had normal flow in all the tendons examined. After 1st match, tendencies to higher intra-tendinous flow were observed in both the dominant patella tendon and non-dominant quadriceps tendon (P-values n.s.). After 2nd match, intra-tendinous flow was significant increased in the dominant patella tendon (P = 0.009). In all other locations, there was a trend towards a stepwise increase in intra-tendinous flow. The preliminary results indicate that high amount of intra-tendinous flow was found in elite badminton players at baseline and was increased after repetitive loading, especially in the patella tendon (dominant leg). The colour Doppler measurement can be used to determine changes in intra-tendinous flow after repetitive loading.