Where is Your Pain? Achilles Tendinopathy Pain Location on Loading Is Different to Palpation, Imaging and Recall Location.

OBJECTIVE: To describe and compare pain maps reported during Achilles tendon loading exercises with recall pain location, in people with pain on palpation in their Achilles tendon and tendon pathology on imaging. DESIGN: Cross-sectional analysis of baseline RCT. METHOD: Participants were recruited from a larger Achilles tendinopathy clinical trial. Inclusion criteria were at least 2-month self-reported history of Achilles tendinopathy, midtendon palpation pain, and pathology on ultrasound tissue characterization. Participants were asked to identify their Achilles tendon pain location on a pain map with 8 prespecified locations while at rest prior to loading (recall pain), and subsequently during tendon loading exercises (loading pain). Participants could select multiple locations or select "other" if the locations did not represent their pain. RESULTS: Ninety-three participants were included (93% of participants from a clinical trial). The locations of pain on loading were diverse; all 8 pain locations (and an "other" option) were represented within this sample. Twenty-five percent of participants did not report pain with loading (n = 23 of 93). Of the 70 participants with loading pain, recall pain location differed to loading pain location in 40% (n = 28 of 70) of the participants. CONCLUSION: Palpation pain location, recall pain location, or location of pathology on imaging were not valid proxies for load-related pain in the Achilles tendon. How different pain locations respond to treatment is unknown. Some pathologies (eg, plantaris) have clear pain locations (eg, medial tendon), and assessing pain location may assist differential diagnosis. J Orthop Sports Phys Ther 2024;54(1):1-9. Epub 7 December 2023. doi:10.2519/jospt.2023.12131.

Can we really say getting stronger makes your tendon feel better? No current evidence of a relationship between change in Achilles tendinopathy pain or disability and changes in Triceps Surae structure or function when completing rehabilitation: A systematic review.

OBJECTIVES: Determine if improvements in pain and disability in patients with mid-portion Achilles tendinopathy relate to changes in muscle structure and function whilst completing exercise rehabilitation. DESIGN: A systematic review exploring the relationship between changes in pain/disability and muscle structure/function over time, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. METHODS: Six online databases and the grey literature were searched from database inception to 16th December 2022 whereas clinical trial registries were searched from database inception to 11th February 2020. We included clinical studies where participants received exercise rehabilitation (±placebo interventions) for mid-portion Achilles tendinopathy if pain/disability and Triceps Surae structure/function were measured. We calculated Cohen's d (95 % confidence intervals) for changes in muscle structure/function over time for individual studies. Data were not pooled due to heterogeneity. Study quality was assessed using a modified Newcastle-Ottawa Scale. RESULTS: Seventeen studies were included for synthesis. No studies reported the relationship between muscle structure/function and pain/disability changes. Twelve studies reported muscle structure/function outcome measures at baseline and at least one follow-up time-point. Three studies reported improvements in force output after treatment; eight studies demonstrated no change in structure or function; one study did not provide a variation measure, precluding within group change over time calculation. All studies were low quality. CONCLUSIONS: No studies explored the relationship between changes in tendon pain and disability and changes in muscle structure and function. It is unclear whether current exercise-based rehabilitation protocols for mid-portion Achilles tendinopathy improve muscle structure or function. SYSTEMATIC REVIEW REGISTRATION: PROSPERO (registration number: CRD42020149970).

Treatment preferences and use of diagnostic imaging in midportion Achilles tendinopathy by Australian allied health professionals.

OBJECTIVES: The objectives of this study were to examine the treatment preferences and use of diagnostic imaging by Australian allied health professionals in the management of midportion Achilles tendinopathy. DESIGN: Cross-sectional survey of Australian allied health professionals. METHODS: An online survey was distributed to registered Australian physiotherapists, podiatrists, myotherapists, exercise physiologists, osteopaths, and chiropractors between September 2018 and October 2019. This survey captured information on clinician demographic, treatment modalities, frequency of use and the reasons for their preferences. A descriptive analysis of the data was employed with nominal and ordinal data analysed using frequency counts. RESULTS: Valid responses were captured from 283 respondents, the majority (229, 80.9%) being physiotherapists. Exercise-based therapy and education were the most commonly used treatments (98.6% and 92.6%, respectively), with the majority of respondents (91.8% and 89.3%) stating that they "always" provided these interventions. Respondents stated that they utilised a number of exercise modalities within the last three years (median = 3, IQR = 3 to 4). Other interventions used as adjunct treatments included heel lifts for shoes (70.0%), massage (59.4%), and taping (40.3%). The majority of respondents (76.7%) never or rarely used diagnostic imaging, citing its limited impact on treatment decision-making and potential for negative impact on patient outcomes. CONCLUSIONS: Australian allied health professionals predominantly use exercise and education, but also use adjuncts such as heel lifts and massage, in the management of midportion Achilles tendinopathy. The results of this study may inform research priorities to generate high quality evidence that best reflects clinical practice.

Differences in Biomechanical Loading Magnitude During a Landing Task in Male Athletes with and without Patellar Tendinopathy.

CONTEXT: Prior research has not established if overloading or underloading movement profiles are present in symptomatic and asymptomatic athletes with patellar tendon structural abnormality (PTA) compared to healthy athletes. OBJECTIVE: The purpose was to compare involved limb landing biomechanics between male athletes with and without patellar tendinopathy. DESIGN: Cross-sectional study Setting: Laboratory Patients or Other Participants: 43 males were grouped based on patellar tendon pain & ultrasound imaging of the proximal patellar tendon: symptomatic with PTA (SYM-PTA; n=13; 20±2yrs; 1.8±0.1m; 84±5kg), asymptomatic with PTA (ASYM-PTA; n=15; 21±2yrs; 1.8±0.1m; 82±13kg), and healthy control (CON; n=15; 20±2yrs; 1.8±0.1m; 79±12kg). MAIN OUTCOME MEASURES: 3D biomechanics were collected during double-limb jump-landing. Kinematic (knee flexion angle (KF)) and kinetic (vertical ground reaction force (VGRF); internal knee extension moment (KEM); patellar tendon force (FPT)) variables were analyzed as continuous waveforms during the stance phase for the involved limb. Mean values were calculated for each 1% of stance, normalized over 202 data points (0-100%), and plotted with 95% confidence intervals. Statistical significance was defined as a lack of 95% CI overlap for ≥ 6 consecutive data points. RESULTS: SYM-PTA had lesser KF than CON throughout the stance phase. ASYM-PTA had lesser KF than CON in the early and late stance phase. SYM-PTA group had lesser KEM and FPT than CON in early stance, as well as ASYM-PTA in mid-stance. CONCLUSIONS: Male athletes with SYM-PTA demonstrated a patellar tendon load-avoidance profile compared to ASYM-PTA and CON athletes. ASYM-PTA did not show evidence of overloading compared to CON. Our findings support the need for individualized treatments for athletes with tendinopathy to maximize load-capacity. TRIAL REGISTRY: ClinicalTrials.gov (#XXX).

Does isometric exercise result in exercise induced hypoalgesia in people with local musculoskeletal pain? A systematic review.

OBJECTIVE: The aim of this review was to investigate if exercise induced hypoalgesia (EIH) occurs following isometric muscle contraction in people with local musculoskeletal symptoms. DESIGN: Systematic review. DATA SOURCES: MEDLINE, EMBASE, CINAHL & SportDiscus electronic databases were searched (inception to April 2020). ELIGIBILITY CRITERIA: Two authors independently evaluated eligibility. Randomised controlled and crossover (repeated measures) trials that measured the effects of isometric exercise in participants with localised musculoskeletal pain during, and up to 2 hours after isometric exercise were included. Other inclusion criteria included comparison to another intervention, or comparison to healthy controls. Primary outcomes were experimentally induced pain thresholds and secondary outcomes included measures of pain sensitivity from clinical testing. RESULTS: 13 studies with data from 346 participants were included for narrative synthesis. EIH was reported in some upper and lower limb studies but there were no consistent data to show isometric exercises were superior to comparison interventions. CONCLUSION: There was no consistent evidence for EIH following isometric exercise in people with musculoskeletal pain. These findings are different to those reported in asymptomatic populations (where EIH is consistently demonstrated) as well as conditions associated with widespread symptoms such as fibromyalgia (where isometric exercise may induce hyperalgesia). Although well tolerated when prescribed, isometric exercise did not induce EIH consistently for people seeking care for local musculoskeletal symptoms. The variance in the dose, location of contraction and intensity of protocols included in this review may explain the inconsistent findings. Further work is required to better understand endogenous analgesia in musculoskeletal pain conditions.

Efficacy of heel lifts versus calf muscle eccentric exercise for mid-portion Achilles tendinopathy (HEALTHY): a randomised trial.

OBJECTIVES: To compare the efficacy of in-shoe heel lifts to calf muscle eccentric exercise in reducing pain and improving function in mid-portion Achilles tendinopathy. METHODS: This was a parallel-group randomised superiority trial at a single centre (La Trobe University Health Sciences Clinic, Discipline of Podiatry, Melbourne, Victoria, Australia). One hundred participants (52 women and 48 men, mean age 45.9, SD 9.4 years) with clinically diagnosed and ultrasonographically confirmed mid-portion Achilles tendinopathy were randomly allocated to either a (1) heel lifts (n=50) or (2) eccentric exercise (n=50) group. The primary outcome measure was the Victorian Institute of Sport Assessment-Achilles (VISA-A) questionnaire at 12 weeks. Differences between groups were analysed using intention to treat with analysis of covariance. RESULTS: There was 80% follow-up of participants (n=40 per group) at 12 weeks. The mean VISA-A score improved by 26.0 points (95% CI 19.6 to 32.4) in the heel lifts group and by 17.4 points (95% CI 9.5 to 25.3) in the eccentric exercise group. On average, there was a between-group difference in favour of the heel lifts for the VISA-A (adjusted mean difference 9.6, 95% CI 1.8 to 17.4, p=0.016), which approximated, but did not meet our predetermined minimum important difference of 10 points. CONCLUSION: In adults with mid-portion Achilles tendinopathy, heel lifts were more effective than calf muscle eccentric exercise in reducing pain and improving function at 12 weeks. However, there is uncertainty in the estimate of effect for this outcome and patients may not experience a clinically worthwhile difference between interventions. TRIAL REGISTRATION NUMBER: ACTRN12617001225303.

Do people with unilateral mid-portion Achilles tendinopathy who participate in running-related physical activity exhibit a meaningful conditioned pain modulation (CPM) effect: a pilot study.

OBJECTIVES: Our primary objective was to report the presence of a conditioned pain modulation (CPM) effect in people with localised mid-portion Achilles tendinopathy and whether changes occur over a 12-week period. Our secondary objectives were to quantify the proportion of participants who present for tendinopathy research with previous interventions or co-morbidities, which may impact the CPM-effect and investigate modulating factors. DESIGN: Prospective, observational cohort pilot study. METHOD: 215 participants presented for this Achilles tendinopathy research and were screened for inclusion with nine being included. Included participants had the CPM-effect (cold-pressor test) assessed using pressure pain thresholds at the Achilles tendon and quantified as absolute, relative and meaningful change at baseline and 12-week follow-up. RESULTS: The most common reasons for exclusion were failure to meet a load-related diagnosis for Achilles tendinopathy (15.5%), presence of confounding other injury (14.1%) and previous injection therapy (13.6%). All participants had a meaningful CPM-effect at baseline and 12-week follow-up. The mean (SD, n) baseline relative CPM effect (reduction in PPTs) was -40.5 (32.7, 9) percent. Moderators of the CPM-effect as well as follow-up changes were not statistically analysed due to a small sample size. CONCLUSION: Based on these data, we would suggest that a homogenous population of patients with chronic, unilateral mid-portion Achilles tendinopathy and no other co-morbidities are likely to exhibit a meaningful CPM-effect. Impairments to endogenous analgesic mechanisms seen in people presenting with mid-portion Achilles tendinopathy may be due to other confounding variables.

Landing biomechanics are not immediately altered by a single-dose patellar tendon isometric exercise protocol in male athletes with patellar tendinopathy: A single-blinded randomized cross-over trial.

OBJECTIVES: To a) determine the acute effects of a single-dose patellar tendon isometric exercise protocol on involved limb landing biomechanics in individuals with patellar tendinopathy and asymptomatic patellar tendon pathology, and b) determine if individuals with patellar tendinopathy demonstrated changes in pain following a single-dose patellar tendon isometric exercise protocol. DESIGN: Single-blinded randomized cross-over trial. SETTING: Laboratory; PARTICIPANTS: 28 young male athletes with symptomatic (n = 13, age: 19.62 ± 1.61) and asymptomatic (n = 15, age: 21.13 ± 1.88) patellar tendinopathy. MAIN OUTCOME MEASURES: Participants completed a single-dose patellar tendon isometric exercise protocol and a sham-TENS protocol, randomized and separated by 7-10 days. Pain-levels during a single-limb decline squat (SLDS) and three-dimensional biomechanics were collected during a double-limb jump-landing task before and after each intervention protocol. A mixed-model repeated measures ANOVA was conducted to compare change scores for all dependent variables. RESULTS: There were no group × intervention interactions for change in pain (F(1, 26) = 0.555, p = 0.463). There was one significant group × intervention interaction for vertical ground reaction force (VGRF) (F(1, 26) = 5.33, p = 0.029). However, post-hoc testing with Bonferroni correction demonstrated no statistical significance for group (SYM: t = -1.679, p = 0.119; ASYM: t = -1.7, p = 0.107) or intervention condition (isometric: t = -2.58, p = 0.016; sham-TENS: 0.72, p = 0.460). There were no further significant group × intervention interactions (p > 0.05). CONCLUSIONS: A single-dose patellar tendon isometric exercise protocol did not have acute effects on landing biomechanics or pain levels in male athletes with patellar tendinopathy or asymptomatic patellar tendon pathology.

Landing Biomechanics, But Not Physical Activity, Differ in Young Male Athletes With and Without Patellar Tendinopathy.

OBJECTIVE: To examine differences in biomechanical and physical activity load in young male athletes with and without patellar tendinopathy. DESIGN: Cross-sectional cohort study. METHODS: Forty-one young male athletes (15-28 years of age) were categorized into 3 distinct groups: symptomatic athletes with patellar tendon abnormalities (PTA) (n = 13), asymptomatic athletes with PTA (n = 14), and a control group of asymptomatic athletes without PTA (n = 14). Participants underwent a laboratory biomechanical jump-landing assessment and wore an accelerometer for 1 week of physical activity monitoring. RESULTS: The symptomatic group demonstrated significantly less patellar tendon force loading impulse in the involved limb compared with both the control and asymptomatic groups (P<.05), with large effects (d = 0.91-1.40). There were no differences in physical activity between the 3 groups (P>.05). CONCLUSION: Young male athletes with symptomatic patellar tendinopathy demonstrated smaller magnitudes of patellar tendon force loading impulse during landing compared to both asymptomatic athletes with patellar tendinopathy and healthy control participants. However, these 3 distinct groups did not differ in general measures of physical activity. Future investigations should examine whether comprehensively monitoring various loading metrics may be valuable to avoid both underloading and overloading patterns in athletes with patellar tendinopathy. J Orthop Sports Phys Ther 2020;50(3):158-166. Epub 6 Jan 2020. doi:10.2519/jospt.2020.9065.

Reduced Levels of Aligned Fibrillar Structure Are Not Associated With Achilles and Patellar Tendon Symptoms.

OBJECTIVE: To investigate whether the mean cross-sectional area (mCSA) of aligned fibrillar structure (AFS) was associated with the presence and severity of symptoms. DESIGN: Prospective cohort study. PARTICIPANTS: One hundred seventy-five elite male Australian football players completed monthly Oslo Sports Trauma Research Center overuse injury questionnaires for both the Achilles and patellar tendon over the season to ascertain the presence and severity of symptoms. At the start of the preseason, participants underwent ultrasound tissue characterization (UTC) imaging of the Achilles and patellar tendon. MAIN OUTCOME MEASURES: Images were classified as normal or abnormal based on gray-scale ultrasound. Based on UTC quantification, the mCSA of AFS was compared between those with and without current symptoms. RESULTS: No difference in the mCSA of AFS was observed between those with or without tendon symptoms (P < 0.05). Similar to previous findings, 80% to 92% of abnormal tendons had similar amounts of mCSA of AFS compared with normal tendon. If reduced mCSA of AFS was present, it was not associated with the presence or severity of symptoms. CONCLUSIONS: The prevalence, development, or severity of symptoms was not associated with decreased levels of AFS in the Achilles or patellar tendon. This suggests that a lack of structural integrity is not linked to symptoms and questions the rationale behind regenerative medicine. Most tendons are able to compensate for areas of disorganization and maintain tissue homeostasis.

How do tendons adapt? Going beyond tissue responses to understand positive adaptation and pathology development: A narrative review.

Understanding how tendons adapt to load is crucial to understanding how training can improve performance, minimise the risk of injury and aid rehabilitation. Adaptation is the positive response of an organism or tissue to benefit its function. In tendons, numerous tissue responses to load have been identified in vivo. Changes in tendon dimensions, structure on imaging, mechanical properties, and blood flow have been reported in response to mechanical stimuli. However, research has focused on tissue level changes with little understanding of how changes at the tissue level affect the person, their athletic performance or injury risk. Tendons can have a paradoxical response to load, load can induce positive adaptation, however it is also a major factor in the development of tendon pathology and pain. Tendon pathology is a risk factor for developing symptoms, yet the high rate of asymptomatic pathology suggests that the pathological tendon must adapt to be able to tolerate load. Similarly, there is mounting evidence to suggest that tendon remodelling or repair is not necessary for a positive clinical outcome following rehabilitation, suggesting that the tendon must adapt via other mechanisms. This narrative review synthesises evidence of how normal and pathological tendons adapts to load, and how this relates to adaptation of load capacity and function of the individual.

MRI findings are associated with time to return to play in first class cricket fast bowlers with side strain in Australia and England.

OBJECTIVES: To investigate the reliability of reporting and relationship between MRI parameters at injury and time to return to play (RTP) in first class cricket fast bowlers with side strain in Australia and England. DESIGN: Cohort study. METHODS: Eighty MRI scans of side strain injuries to 57 fast bowlers were sourced. Ten scans were reported by three experienced radiologists to determine intra- and inter-rater reliability. The relationship between six MRI parameters (muscle injured, presence of a muscle tear, rib level of injury, presence of blood fluid products/haematoma, periosteal stripping, rib oedema) and time to RTP was investigated with 39 scans reported by a single radiologist with known intra-rater reliability. The association between parameters and time to RTP was analysed with an ordinal logistic regression model. RESULTS: Recovery time was prolonged with a mean of 39days (standard deviation: 14days) and 44% of bowlers requiring more than 6weeks to RTP. Reliability levels between parameters varied widely. The presence or absence of a muscle tear was the only MRI parameter associated with time to RTP. Players with a muscle tear were 8 times more likely to take more than 6weeks to RTP. The multifactorial model was predictive of recovery time in only 53% of this cohort, leaving 47% of total variance in time to RTP unexplained. CONCLUSIONS: The presence of a muscle tear was associated with time to RTP in cricket fast bowlers with side strain injury in first class cricket in Australia and England.

Efficacy of heel lifts versus calf muscle eccentric exercise for mid-portion Achilles tendinopathy (the HEALTHY trial): study protocol for a randomised trial.

BACKGROUND: Mid-portion Achilles tendinopathy is a common musculoskeletal condition characterised by degeneration of the Achilles tendon, which causes pain and disability. Multiple non-surgical treatments have been advocated for this condition including calf muscle eccentric exercise and in-shoe heel lifts. Although adherence is challenging, there is evidence to suggest that calf muscle eccentric exercise is effective in decreasing pain and improving function in people with Achilles tendinopathy. Heel lifts reduce ankle joint dorsiflexion and Achilles tendon strain, however their efficacy in the management of Achilles tendinopathy is unclear. This article describes the design of a parallel-group randomised trial comparing the efficacy of heel lifts to calf muscle eccentric exercise for Achilles tendinopathy. METHODS: Ninety-two participants with Achilles tendinopathy will be randomised to one of two groups: (i) a heel lift group that will receive pre-fabricated 12 mm in-shoe heel lifts (Clearly Adjustable®), or (ii) an exercise group that will be advised to carry out a calf muscle eccentric exercise program (twice a day, 7 days a week, for 12 weeks). Outcome measures will be obtained at baseline, 2, 6 and 12 weeks; the primary endpoint for assessing efficacy being 12 weeks. The primary outcome measure will be the total score of the Victorian Institute of Sport Assessment - Achilles (VISA-A) questionnaire. Secondary outcome measures will include thickness and integrity of the Achilles tendon (using ultrasound tissue characterisation [UTC]), participant perception of treatment effect on pain and function (using the 7-point Patient Global Impression of Change scale), severity of pain at the Achilles tendon (using a 100 mm visual analogue scale) in the previous week, health status (using the EuroQol-5D-5L™ questionnaire), physical activity levels (using the 7-day Recall Physical Activity Questionnaire) and calf muscle function (using the standing heel rise test). Data will be analysed using the intention to treat principle. DISCUSSION: The HEALTHY trial (Heel lifts versus calf muscle eccentric Exercise for AchiLles TendinopatHY) is the first randomised trial to compare the efficacy of heel lifts to calf muscle eccentric exercise in reducing pain and improving function in people with Achilles tendinopathy. A pragmatically designed trial was developed to ensure that if the interventions are found to be effective, the findings can be readily implemented in clinical practice. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12617001225303. Registered on August 22nd, 2017.

Quantification of Achilles and patellar tendon structure on imaging does not enhance ability to predict self-reported symptoms beyond grey-scale ultrasound and previous history.

BACKGROUND: Tendon pathology on imaging has been associated with an increased risk of developing symptoms. This evidence is based on classifying the tendon as normal or pathological. It is unclear whether the extent of tendon pathology is associated with the development or severity of symptoms. OBJECTIVES: To investigate whether the presence and extent of tendon pathology on ultrasound tissue characterisation (UTC), or a previous history of symptoms, were associated with the development of symptoms over a football season. METHODS: 179 male Australian football players underwent UTC imaging of their Achilles and/or patellar tendon at the start of the pre-season. Players completed monthly OSTRC overuse questionnaires to quantify the presence and severity of Achilles and/or patellar tendon symptoms. Risk factor analysis was performed to identify associations between imaging and the development of symptoms. RESULTS: A pathological Achilles tendon increased the risk of developing symptoms (RR=3.2, 95%CI 1.7-5.9). Conversely, a pathological patellar tendon was not significantly associated with the development of symptoms (RR=1.8, 95%CI 0.9-3.7). Quantification of tendon structure using UTC did not enhance the ability to identify athletes who developed symptoms. Previous history of symptoms was the strongest predictor for the development of symptoms (Achilles RR=3.0 95%CI 1.8-4.8; patellar RR=3.7 95%CI 2.2-6.1). CONCLUSION: Tendon pathology was associated with the development of self-reported symptoms; however previous history of symptoms was a stronger risk factor. The extent of disorganisation quantified by UTC should not be used as a marker for the presence or severity of current and future symptoms.

El continuum de la patología de tendón: concepto actual e implicaciones clínicas / The continuum of tendon pathology: Current view and clinical implications

El modelo del continuum fue propuesto por Cook y Purdam en 2009 con el propósito de mejorar la comprensión del complejo marco que rodea la patología del tendón. El concepto se basa en las características de los tres estados tisulares del tendón: tendón reactivo, tendinopatía desestructurada y tendinopatía degenerativa. El concepto del continuum se diferencia de las otras propuestas por su visión de cambio continuo de la estructura del tejido tendinoso. Cada fase tiene una presentación clínica característica y un tratamiento específico. Estudios histológicos, por la imagen y clínicos corroboran con evidencia el abordaje de esta patología mediante el concepto del modelo de continuum (AU)

Cook and Purdam first proposed the Continuum model in 2009, with the aim of improving the understanding of the complexity of tendon pathologies. The Continuum is based on three states of tendon structure: reactive tendon, tendon disrepair and degenerative tendon. In contrast to other proposals, the Continuum model describes continuous changes in tendon structure. Each state of tendon structure represents a particular clinical presentation and requires a particular type of management. Evidence seen in histopathological studies, imaging and clinical studies all support the Continuum model for the analysis of tendon pathologies (AU)

Do isometric and isotonic exercise programs reduce pain in athletes with patellar tendinopathy in-season? A randomised clinical trial.

OBJECTIVES: Many athletes with patellar tendinopathy participate in sports with symptoms during or after activities. Current treatments do not decrease pain in-season; eccentric exercises in-season result in an increase in pain. This study examined if isometric and isotonic exercises relieved pain in competing athletes with patellar tendinopathy. DESIGN: Randomised clinical trial. METHODS: Jumping athletes with patellar tendinopathy playing at least three times per week participated in this study. Athletes were randomised into an isometric or isotonic exercise group. The exercise programs consisted of four isometric or isotonic exercise sessions per week for four weeks. Pain during a single leg decline squat (SLDS) on a Numeric Rating Scale (NRS; 0-10) was used as the main outcome measure; measurements were completed at baseline and at 4-week follow-up. RESULTS: Twenty-nine athletes were included in this study. Median pain scores improved significantly over the 4-week intervention period in both the isometric group (Z=-2.527, p=0.012, r=-0.63) and isotonic group (Z=-2.952, p=0.003, r=-0.63). There was no significant difference in NRS pain score change (U=29.0, p=0.208, r=0.29) between the isometric group (median (IQR), 2.5 (1-4.5)) and isotonic group (median (IQR), 3.0 (2-6)). CONCLUSIONS: This is the first study to show a decrease in patellar tendon pain without a modification of training and competition load and the first study to investigate isometric exercises in a clinical setting. Both isometric and isotonic exercise programs are easy-to-use exercises that can reduce pain from patellar tendinopathy for athletes in-season.

Does type 1 diabetes mellitus affect Achilles tendon response to a 10 km run? A case control study.

BACKGROUND: Achilles tendon structure deteriorates 2-days after maximal loading in elite athletes. The load-response behaviour of tendons may be altered in type 1 diabetes mellitus (T1DM) as hyperglycaemia accelerates collagen cross-linking. This study compared Achilles tendon load-response in participants with T1DM and controls. METHODS: Achilles tendon structure was quantified at day-0, day-2 and day-4 after a 10 km run. Ultrasound tissue characterisation (UTC) measures tendon structural integrity by classifying pixels as echo-type I, II, III or IV. Echo-type I has the most aligned collagen fibrils and IV has the least. RESULTS: Participants were 7 individuals with T1DM and 10 controls. All regularly ran distances greater than 5 km and VISA-A scores indicated good tendon function (T1DM = 94 ± 11, control = 94 ± 10). There were no diabetic complications and HbA1c was 8.7 ± 2.6 mmol/mol for T1DM and 5.3 ± 0.4 mmol/mol for control groups. Baseline tendon structure was similar in T1DM and control groups - UTC echo-types (I-IV) and anterior-posterior thickness were all p > 0.05. No response to load was seen in either T1DM or control group over the 4-days post exercise. CONCLUSION: Active individuals with T1DM do not have a heightened Achilles tendon response to load, which suggests no increased risk of tendon injury. We cannot extrapolate these findings to sedentary individuals with T1DM.

Is higher serum cholesterol associated with altered tendon structure or tendon pain? A systematic review.

BACKGROUND: Tendon pain occurs in individuals with extreme cholesterol levels (familial hypercholesterolaemia). It is unclear whether the association with tendon pain is strong with less extreme elevations of cholesterol. OBJECTIVE: To determine whether lipid levels are associated with abnormal tendon structure or the presence of tendon pain. METHODS: We conducted a systematic review and meta-analysis. Relevant articles were found through an electronic search of 6 medical databases-MEDLINE, Cochrane, AMED, EMBASE, Web of Science and Scopus. We included all case-control or cross-sectional studies with data describing (1) lipid levels or use of lipid-lowering drugs and (2) tendon structure or tendon pain. RESULTS: 17 studies (2612 participants) were eligible for inclusion in the review. People with altered tendon structure or tendon pain had significantly higher total cholesterol, low-density lipoprotein cholesterol and triglycerides, as well as lower high-density lipoprotein cholesterol; with mean difference values of 0.66, 1.00, 0.33, and -0.19 mmol/L, respectively. CONCLUSIONS: The results of this review indicate that a relationship exists between an individual's lipid profile and tendon health. However, further longitudinal studies are required to determine whether a cause and effect relationship exists between tendon structure and lipid levels. This could lead to advancement in the understanding of the pathoaetiology and thus treatment of tendinopathy.

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.

Structural integrity is decreased in both Achilles tendons in people with unilateral Achilles tendinopathy.

OBJECTIVES: A high proportion of Achilles tendinopathy patients develop bilateral symptoms with human and animal studies showing bilateral histological changes associated with overuse/pathology in one tendon. The current study examined changes in tendon structure, assessed semi-quantitatively using ultrasound tissue characterisation, in both the symptomatic and asymptomatic tendon in unilateral Achilles tendinopathy patients in comparison to individuals with no history of tendinopathy. DESIGN: Cross-sectional case-control study. METHODS: Participants with Achilles tendinopathy (n=21), with varying severity and length of clinical symptoms, and six participants with no history of tendinopathy were recruited. Tendons were scanned using ultrasound tissue characterisation, which captures contiguous transverse ultrasound images every 0.2mm and renders a 3-dimensional image. Ultrasound tissue characterisation quantifies tendon structure by measuring the stability of echopattern over contiguous transverse images. Four echo-types were discriminated and expressed as a percentage. Antero-posterior diameter of all tendons was measured. RESULTS: Significant differences were observed in the proportion of normal tendon structure between all three groups (p<0.01), with the symptomatic tendon containing the least amount of normal tendon structure (symptomatic - 79.5%, asymptomatic - 81.8%, control - 86.4%). The asymptomatic tendon contained significantly less normal tendon in comparison to the control tendon (p=0.008), suggesting the asymptomatic tendon is structurally compromised despite the absence of symptoms. CONCLUSIONS: Both Achilles tendons are structurally compromised in patients with unilateral Achilles tendinopathy. Future studies need to investigate whether these changes increase the risk of developing symptoms.