The VISA-A (sedentary) should be used for sedentary patients with Achilles tendinopathy: a modified version of the VISA-A developed and evaluated in accordance with the COSMIN checklist.

OBJECTIVE: To develop and evaluate a modified version of the Victorian Institute of Sport Assessment-Achilles (VISA-A) questionnaire, for use in sedentary patients with Achilles tendinopathy, using the Consensus-based Standards for the selection of health Measurement Instruments recommendations. METHODS: Twenty-two sedentary patients with Achilles tendinopathy completed the VISA-A and provided feedback regarding the relevance, comprehensiveness and comprehensibility of each item, response options and instructions. Patient and professional feedback was used to develop the VISA-A (sedentary) questionnaire. Reliability, validity and responsiveness of the VISA-A (sedentary) was evaluated in 51 sedentary patients with Achilles tendinopathy: 47.1% women, mean age 64.8 (SD 11.24). RESULTS: Factor analysis identified two dimensions (symptoms and activity) for the VISA-A (sedentary). Test-retest reliability was excellent for symptoms (intraclass correlation coefficient, ICC=0.991) and activity (ICC=0.999). Repeatability was 1.647 for symptoms and 0.549 for activity. There was a significant difference between the VISA-A and VISA-A (sedentary) scores both pretreatment and post-treatment. There was stronger correlation between the pretreatment to post-treatment change in the VISA-A (sedentary) scores (r=0.420 for symptoms, r=0.407 for activity) and the global rating of change than the VISA-A scores (r=0.253 for symptoms, r=0.186 for activity). CONCLUSION: The VISA-A (sedentary) demonstrates adequate reliability, validity and responsiveness in sedentary patients with Achilles tendinopathy. The VISA-A (sedentary) is a more appropriate measure than the VISA-A for this cohort and is recommended for clinical and research purposes.

Chronic hyperglycemia, hypercholesterolemia, and metabolic syndrome are associated with risk of tendon injury.

Tendon injury is a considerable problem affecting both physically active and sedentary people. The aim of this study was to examine the relationship between markers for metabolic disorders (hyperglycemia, hypercholesterolemia, and metabolic syndrome) and the risk of developing tendon injuries requiring referral to a hospital. The Copenhagen City Heart Study is a prospective study of diabetic and non-diabetic individuals from the Danish general population with different physical activity levels. The cohort was followed for 3 years via national registers with respect to tendon injuries. Data from 5856 individuals (median age 62 years) were included. The overall incidence of tendon injury in both upper and lower extremities that required an out-patient or in-house visit to a hospital was ~5.7/1000 person years. Individuals with elevated HbA1c (glycated hemoglobin) even in the prediabetic range (HbA1c>5.7%) had a ~3 times higher risk of tendon injury in the lower extremities only, as compared to individuals with normal HbA1C levels. Hypercholesterolemia (total cholesterol>5 mmol/L) increased risk of tendon injury in the upper extremities by ~1.5 times, and individuals with metabolic syndrome had ~2.5 times higher risk of tendon injury in both upper and lower extremities. In conclusion, these data demonstrate for the first time in a large cohort with different physical activity levels that the indicators for metabolic syndrome are a powerful systemic determinant of tendon injury, and two of its components, hyperglycemia and hypercholesterolemia, each independently make tendons susceptible for damage and injury.

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.

Does moxonidine reduce Achilles tendon or musculoskeletal pain in women with polycystic ovarian syndrome? A secondary analysis of a randomised controlled trial.

BACKGROUND: Sympathetic activity and insulin resistance have recently been linked with chronic tendon and musculoskeletal pain. Polycystic ovarian syndrome is linked with insulin resistance and increased sympathetic drive and was therefore an appropriate condition to study the effects of modulating sympathetic activity on Achilles tendon and musculoskeletal symptoms. METHODS: A secondary analysis of a double-blinded, randomised controlled trial on women with polycystic ovarian syndrome was conducted. Participants received 12 weeks of moxonidine (n = 14) or placebo (n = 18). Musculoskeletal symptom and Victorian Institute of Sport Assessment - Achilles (VISA-A) questionnaires were distributed, and ultrasound tissue characterisation quantified tendon structure at 0 and 12 weeks. 2-way ANOVA was used for multiple comparisons. RESULTS: There was no difference in mean change in musculoskeletal symptoms (- 0.6 ± 1.7 vs - 0.4 ± 1.8, p = 0.69) or VISA-A (moxonidine - 0.2 ± 8.8 vs placebo + 4.2 ± 14.6, p = 0.24) attributable to the intervention. There was no difference in any measures of Achilles structure. Moxonidine did not reduce sympathetic drive when compared to placebo. CONCLUSIONS: This was the first study to investigate the effects of blocking sympathetic drive on musculoskeletal and Achilles tendon symptoms in a metabolically diverse population. While the study was limited by small sample size and lack of sympathetic modulation, moxonidine did not change tendon pain/structure or musculoskeletal symptoms. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01504321 . Registered 5 January 2012.

Compression Therapy to Prevent Recurrent Cellulitis of the Leg.

BACKGROUND: Chronic edema of the leg is a risk factor for cellulitis. Daily use of compression garments on the leg has been recommended to prevent the recurrence of cellulitis, but there is limited evidence from trials regarding its effectiveness. METHODS: In this single-center, randomized, nonblinded trial, we assigned participants with chronic edema of the leg and recurrent cellulitis, in a 1:1 ratio, to receive leg compression therapy plus education on cellulitis prevention (compression group) or education alone (control group). Follow-up occurred every 6 months for up to 3 years or until 45 episodes of cellulitis had occurred in the trial. The primary outcome was the recurrence of cellulitis. Participants in the control group who had an episode of cellulitis crossed over to the compression group. Secondary outcomes included cellulitis-related hospital admission and quality-of-life assessments. RESULTS: A total of 183 patients were screened, and 84 were enrolled; 41 participants were assigned to the compression group, and 43 to the control group. At the time of a planned interim analysis, when 23 episodes of cellulitis had occurred, 6 participants (15%) in the compression group and 17 (40%) in the control group had had an episode of cellulitis (hazard ratio, 0.23; 95% confidence interval [CI], 0.09 to 0.59; P = 0.002; relative risk [post hoc analysis], 0.37; 95% CI, 0.16 to 0.84; P = 0.02), and the trial was stopped for efficacy. A total of 3 participants (7%) in the compression group and 6 (14%) in the control group were hospitalized for cellulitis (hazard ratio, 0.38; 95% CI, 0.09 to 1.59). Most quality-of-life outcomes did not differ between the two groups. No adverse events occurred during the trial. CONCLUSIONS: In this small, single-center, nonblinded trial involving patients with chronic edema of the leg and cellulitis, compression therapy resulted in a lower incidence of recurrence of cellulitis than conservative treatment. (Funded by Calvary Public Hospital Bruce; Australian and New Zealand Clinical Trials Registry number, ACTRN12617000412336.).

Impact of Compression Therapy on Cellulitis (ICTOC) in adults with chronic oedema: a randomised controlled trial protocol.

INTRODUCTION: Cellulitis represents a significant burden to patients' quality of life (QOL) and cost to the healthcare system, especially due to its recurrent nature. Chronic oedema is a strong risk factor for both an initial episode of cellulitis and cellulitis recurrence. Expert consensus advises compression therapy to prevent cellulitis recurrence in individuals with chronic oedema, however, there is little supporting evidence. This research aims to determine if the management of chronic oedema using compression therapy effectively delays the recurrence of lower limb cellulitis. METHODS AND ANALYSIS: A randomised controlled trial with cross-over will be used to assess the impact of compression therapy on clinical outcomes (time to next episode of cellulitis, rate of cellulitis-related hospital presentations, QOL and leg volume). Using concealed allocation, 162 participants will be randomised into the intervention (compression) or control (no compression) group. Randomisation will be stratified by prophylactic antibiotic use. Participants will be followed up at 6 monthly intervals for up to 3 years or until 45 episodes of cellulitis occur across the cohort. Following an episode of recurrent cellulitis, control group participants will cross-over to the intervention group. Survival analysis will be undertaken to assess the primary outcome measure of time to cellulitis recurrence. The hypotheses are that compression therapy to control lower limb chronic oedema will delay recurrent lower limb cellulitis, reduce the rate of associated hospitalisations, minimise affected limb volume and improve the QOL of this population. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the ethics committees of all relevant institutions. Results will be disseminated through relevant peer-reviewed journal articles and conference presentations. TRIAL REGISTRATION NUMBER: ACTRN12617000412336; Pre-results. The ICTOC trial is currently in progress. Participant recruitment started in May 2017 and is expected to continue until December 2019.

Oral Supplementation of Specific Collagen Peptides Combined with Calf-Strengthening Exercises Enhances Function and Reduces Pain in Achilles Tendinopathy Patients.

The current pilot study investigates whether oral supplementation of specific collagen peptides improves symptoms and tendon vascularisation in patients with chronic mid-portion Achilles tendinopathy in combination with structured exercise. Participants were given a placebo or specific collagen peptides (TENDOFORTE®) in combination with a bi-daily calf-strengthening program for 6 months. Group AB received specific collagen peptides for the first 3 months before crossing over to placebo. Group BA received placebo first before crossing over to specific collagen peptides. At baseline (T1), 3 (T2) and 6 (T3) months, Victorian Institute of Sports Assessment⁻Achilles (VISA-A) questionnaires and microvascularity measurements through contrast-enhanced ultrasound were obtained in 20 patients. Linear mixed modeling statistics showed that after 3 months, VISA-A increased significantly for group AB with 12.6 (9.7; 15.5), while in group BA VISA-A increased only by 5.3 (2.3; 8.3) points. After crossing over group AB and BA showed subsequently a significant increase in VISA-A of, respectively, 5.9 (2.8; 9.0) and 17.7 (14.6; 20.7). No adverse advents were reported. Microvascularity decreased in both groups to a similar extent and was moderately associated with VISA-A (Rc²:0.68). We conclude that oral supplementation of specific collagen peptides may accelerate the clinical benefits of a well-structured calf-strengthening and return-to-running program in Achilles tendinopathy patients.

Is there an association between metabolic syndrome and rotator cuff-related shoulder pain? A systematic review.

OBJECTIVES: Rotator cuff-related shoulder pain (RCRSP) is a common upper limb complaint. It has been suggested that this condition is more common among people with cardiometabolic risk factors. This systematic review has synthesised evidence from case-control, cross-sectional and cohort studies on the association between metabolic syndrome (MetS) and RCRSP. DESIGN AND DATA SOURCES: Five medical databases (MEDLINE, EMBASE, SCOPUS, CINAHL and AMED) and reference checking methods were used to identify all relevant English articles that considered MetS and RCRSP. Studies were appraised using the Newcastle-Ottawa Scale (NOS). Two reviewers performed critical appraisal and data extraction. Narrative synthesis was performed via content analysis of statistically significant associations. RESULTS: Three cross-sectional, two case-control and one cohort study met the inclusion criteria, providing a total of 1187 individuals with RCRSP. Heterogeneity in methodology and RCRSP or MetS definition precluded a meaningful meta-analysis. Four of the included studies identified associations between the prevalence of MetS and RCRSP. Studies consistently identified independent cardiometabolic risk factors associated with RCRSP. All studies were level III evidence. SUMMARY AND CONCLUSION: The low-moderate quality evidence included in this review suggests an association between MetS and RCRSP. Most studies demonstrated moderate quality on appraisal. The direction of association and cardiometabolic factors influencing should be investigated by longitudinal and treatment studies. These preliminary conclusions and clinical utility should be treated with caution due to limitations of the evidence base.

Don't Assume the Control Group Is Normal-People with Asymptomatic Tendon Pathology Have Higher Pressure Pain Thresholds.

Objective: Pain pressure thresholds (PPT) are used to study peripheral and central pain processing. In the tendon, pathological changes may exist without pain. This pilot study aimed to compare PPT between individuals with normal tendons and asymptomatic tendon pathology, and between individuals with and without a history of tendon pain. Methods: The patellar, Achilles, and supraspinatus tendons of 128 asymptomatic participants were examined with ultrasound. Global PPT average was determined using a digital algometer at the patellar tendon, quadriceps muscle, L3 spinous process, and deltoid muscle insertion. Participants were separated into three groups: (1) healthy control group (no pathology, no history of pain), (2) tendon pathology at any site without a history of pain, (3) history of tendon pain anywhere. Results: There were 92 controls, seven with asymptomatic pathology and 29 with a history of tendon pain. Asymptomatic tendon pathology at any site (without a history of pain) was associated with globally increased PPTs compared with controls (P < 0.001, pathology N = 7, N = 92 controls). Matched pair analysis remained significant (P < 0.004). A history of tendon pain was associated with globally increased PPTs compared with the control group (P = 0.026). Matched pair analysis was not significant (P = 0.122). Conclusions: Asymptomatic tendon pathology is associated with higher PPTs. These findings point toward central nervous system adaptations but in a novel way-central desensitization. This challenges the validity of conclusions drawn from PPT studies that do not verify normal structure in the control group; artificial inflation of control group data may incorrectly indicate decreased PPTs in the comparison group.

Is subsequent lower limb injury associated with previous injury? A systematic review and meta-analysis.

BACKGROUND: Previous injury is a strong risk factor for recurrent lower limb injury in athletic populations, yet the association between previous injury and a subsequent injury different in nature or location is rarely considered. OBJECTIVE: To systematically review data on the risk of sustaining a subsequent lower limb injury different in nature or location following a previous injury. METHODS: Eight medical databases were searched. Studies were eligible if they reported lower limb injury occurrence following any injury of a different anatomical site and/or of a different nature, assessed injury risk, contained athletic human participants and were written in English. Two reviewers independently applied the eligibility criteria and performed the risk of bias assessment. Meta-analysis was conducted using a random effects model. RESULTS: Twelve studies satisfied the eligibility criteria. Previous history of an ACL injury was associated with an increased risk of subsequent hamstring injury (three studies, RR=2.25, 95% CI 1.34 to 3.76), but a history of chronic groin injury was not associated with subsequent hamstring injury (three studies, RR=1.14, 95% CI 0.29 to 4.51). Previous lower limb muscular injury was associated with an increased risk of sustaining a lower limb muscular injury at a different site. A history of concussion and a variety of joint injuries were associated with an increased subsequent lower limb injury risk. CONCLUSIONS: The fact that previous injury of any type may increase the risk for a range of lower limb subsequent injuries must be considered in the development of future tertiary prevention programmes. SYSTEMATIC REVIEW REGISTRATION NUMBER: CRD42016039904 (PROSPERO).

Isometric Contractions Are More Analgesic Than Isotonic Contractions for Patellar Tendon Pain: An In-Season Randomized Clinical Trial.

OBJECTIVE: This study aimed to compare the immediate analgesic effects of 2 resistance programs in in-season athletes with patellar tendinopathy (PT). Resistance training is noninvasive, a principle stimulus for corticospinal and neuromuscular adaptation, and may be analgesic. DESIGN: Within-season randomized clinical trial. Data analysis was conducted blinded to group. SETTING: Subelite volleyball and basketball competitions. PARTICIPANTS: Twenty jumping athletes aged more than 16 years, participating in games/trainings 3 times per week with clinically diagnosed PT. INTERVENTIONS: Two quadriceps resistance protocols were compared; (1) isometric leg extension holds at 60 degrees knee flexion (80% of their maximal voluntary isometric contraction) or (2) isotonic leg extension (at 80% of their 8 repetition maximum) 4 times per week for 4 weeks. Time under load and rest between sets was matched between groups. MAIN OUTCOME MEASURES: (1) Pain (0-10 numerical rating score) during single leg decline squat (SLDS), measured preintervention and postintervention sessions. (2) VISA-P, a questionnaire about tendon pain and function, completed at baseline and after 4 weeks. RESULTS: Twenty athletes with PT (18 men, mean 22.5 ± 4.7 years) participated (isotonic n = 10, isometric n = 10). Baseline median SLDS pain was 5/10 for both groups (isotonic range 1-8, isometric range 2-8). Isometric contractions produced significantly greater immediate analgesia (P < 0.002). Week one analgesic response positively correlated with improvements in VISA-P at 4 weeks (r = 0.64). CONCLUSIONS: Both protocols appear efficacious for in-season athletes to reduce pain, however, isometric contractions demonstrated significantly greater immediate analgesia throughout the 4-week trial. Greater analgesia may increase the ability to load or perform.

Rehabilitation of Tendon Problems in Patients with Diabetes Mellitus.

Exercise is crucial in the management of diabetes mellitus and its associated complications. However, individuals with diabetes have a heightened risk of musculoskeletal problems, including tendon pathologies. Diabetes has a significant impact on the function of tendons due to the accumulation of advanced glycation end-products in the load-bearing collagen. In addition, tendon vascularity and healing may be reduced due to diabetes-induced changes in the peripheral vascular system, and impaired synthesis of collagen and glycosaminoglycan. The current chapter presents an evidence-based discussion of considerations for the rehabilitation of tendon problems in people with diabetes. The following conditions are discussed in detail - calcific tendinopathy, tenosynovitis, tendon rupture, and non-calcifying tendinopathy. Common diabetes-related findings are presented, along with their potential impact on tendinopathy management and suggested modifications to standard tendinopathy treatment protocols. A holistic approach should be used to optimize musculotendinous function, including a comprehensive exercise prescription addressing strength, flexibility, and aerobic fitness.

Tendon neuroplastic training: changing the way we think about tendon rehabilitation: a narrative review.

Tendinopathy can be resistant to treatment and often recurs, implying that current treatment approaches are suboptimal. Rehabilitation programmes that have been successful in terms of pain reduction and return to sport outcomes usually include strength training. Muscle activation can induce analgesia, improving self-efficacy associated with reducing one's own pain. Furthermore, strength training is beneficial for tendon matrix structure, muscle properties and limb biomechanics. However, current tendon rehabilitation may not adequately address the corticospinal control of the muscle, which may result in altered control of muscle recruitment and the consequent tendon load, and this may contribute to recalcitrance or symptom recurrence. Outcomes of interest include the effect of strength training on tendon pain, corticospinal excitability and short interval cortical inhibition. The aims of this concept paper are to: (1) review what is known about changes to the primary motor cortex and motor control in tendinopathy, (2) identify the parameters shown to induce neuroplasticity in strength training and (3) align these principles with tendon rehabilitation loading protocols to introduce a combination approach termed as tendon neuroplastic training. Strength training is a powerful modulator of the central nervous system. In particular, corticospinal inputs are essential for motor unit recruitment and activation; however, specific strength training parameters are important for neuroplasticity. Strength training that is externally paced and akin to a skilled movement task has been shown to not only reduce tendon pain, but modulate excitatory and inhibitory control of the muscle and therefore, potentially tendon load. An improved understanding of the methods that maximise the opportunity for neuroplasticity may be an important progression in how we prescribe exercise-based rehabilitation in tendinopathy for pain modulation and potentially restoration of the corticospinal control of the muscle-tendon complex.

Is there an association between tendinopathy and diabetes mellitus? A systematic review with meta-analysis.

BACKGROUND: Musculoskeletal symptoms limit adherence to exercise interventions for individuals with type 2 diabetes. People with diabetes may be susceptible to tendinopathy due to chronically elevated blood glucose levels. Therefore, we aimed to investigate this potential association by systematically reviewing and meta-analysing case-control, cross-sectional, and studies that considered both of these conditions. METHODS: Nine medical databases and hand searching methods were used without year limits to identify all relevant English language articles that considered diabetes and tendinopathy. Two authors applied exclusion criteria and one author extracted data with verification by a second author. Meta-analysis was conducted using a random effects model. Results were expressed as odds ratio (OR), mean difference or standardised mean difference with a confidence intervals (95% CI). Heterogeneity was assessed by I(2). FINDINGS: 31 studies were included in the final analysis of which 26 recruited people with diabetes and five recruited people with tendinopathy. Tendinopathy was more prevalent in people with diabetes (17 studies, OR 3·67, 95% CI 2·71 to 4·97), diabetes was more prevalent in people with tendinopathy (5 studies, OR 1·28, 95% CI 1·10 to 1·49), people with diabetes and tendinopathy had a longer duration of diabetes than people with diabetes only (6 studies, mean difference 5·26 years, 95% CI 4·15 to 6·36) and people with diabetes had thicker tendons than controls (9 studies, standardised mean difference 0·79 95% CI 0·47 to 1·12). INTERPRETATION: These findings provide strong evidence that diabetes is associated with higher risk of tendinopathy. This is clinically relevant as tendinopathy may affect adherence to exercise interventions for diabetes.

Translating Evidence Into Practice via Social Media: A Mixed-Methods Study.

BACKGROUND: Approximately 80% of research evidence relevant to clinical practice never reaches the clinicians delivering patient care. A key barrier for the translation of evidence into practice is the limited time and skills clinicians have to find and appraise emerging evidence. Social media may provide a bridge between health researchers and health service providers. OBJECTIVE: The aim of this study was to determine the efficacy of social media as an educational medium to effectively translate emerging research evidence into clinical practice. METHODS: The study used a mixed-methods approach. Evidence-based practice points were delivered via social media platforms. The primary outcomes of attitude, knowledge, and behavior change were assessed using a preintervention/postintervention evaluation, with qualitative data gathered to contextualize the findings. RESULTS: Data were obtained from 317 clinicians from multiple health disciplines, predominantly from the United Kingdom, Australia, the United States, India, and Malaysia. The participants reported an overall improvement in attitudes toward social media for professional development (P<.001). The knowledge evaluation demonstrated a significant increase in knowledge after the training (P<.001). The majority of respondents (136/194, 70.1%) indicated that the education they had received via social media had changed the way they practice, or intended to practice. Similarly, a large proportion of respondents (135/193, 69.9%) indicated that the education they had received via social media had increased their use of research evidence within their clinical practice. CONCLUSIONS: Social media may be an effective educational medium for improving knowledge of health professionals, fostering their use of research evidence, and changing their clinical behaviors by translating new research evidence into clinical practice.

Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy.

BACKGROUND: Few interventions reduce patellar tendinopathy (PT) pain in the short term. Eccentric exercises are painful and have limited effectiveness during the competitive season. Isometric and isotonic muscle contractions may have an immediate effect on PT pain. METHODS: This single-blinded, randomised cross-over study compared immediate and 45 min effects following a bout of isometric and isotonic muscle contractions. Outcome measures were PT pain during the single-leg decline squat (SLDS, 0-10), quadriceps strength on maximal voluntary isometric contraction (MVIC), and measures of corticospinal excitability and inhibition. Data were analysed using a split-plot in time-repeated measures analysis of variance (ANOVA). RESULTS: 6 volleyball players with PT participated. Condition effects were detected with greater pain relief immediately from isometric contractions: isometric contractions reduced SLDS (mean±SD) from 7.0±2.04 to 0.17±0.41, and isotonic contractions reduced SLDS (mean±SD) from 6.33±2.80 to 3.75±3.28 (p<0.001). Isometric contractions released cortical inhibition (ratio mean±SD) from 27.53%±8.30 to 54.95%±5.47, but isotonic contractions had no significant effect on inhibition (pre 30.26±3.89, post 31.92±4.67; p=0.004). Condition by time analysis showed pain reduction was sustained at 45 min postisometric but not isotonic condition (p<0.001). The mean reduction in pain scores postisometric was 6.8/10 compared with 2.6/10 postisotonic. MVIC increased significantly following the isometric condition by 18.7±7.8%, and was significantly higher than baseline (p<0.001) and isotonic condition (p<0.001), and at 45 min (p<0.001). CONCLUSIONS: A single resistance training bout of isometric contractions reduced tendon pain immediately for at least 45 min postintervention and increased MVIC. The reduction in pain was paralleled by a reduction in cortical inhibition, providing insight into potential mechanisms. Isometric contractions can be completed without pain for people with PT. The clinical implications are that isometric muscle contractions may be used to reduce pain in people with PT without a reduction in muscle strength.

Serum levels of oxylipins in achilles tendinopathy: an exploratory study.

BACKGROUND: Linoleic acid-derived oxidation products are found in experimental pain models. However, little is known about the levels of such oxylipins in human pain. In consequence, in the present study, we have undertaken a lipidomic profiling of oxylipins in blood serum from patients with Achilles tendinopathy and controls. METHODOLOGY/PRINCIPAL FINDINGS: A total of 34 oxylipins were analysed in the serum samples. At a significance level of P<0.00147 (<0.05/34), two linoleic acid-derived oxylipins, 13-hydroxy-10E,12Z-octadecadienoic (13-HODE) and 12(13)-dihydroxy-9Z-octadecenoic acid (12,13-DiHOME) were present at significantly higher levels in the Achilles tendinopathy samples. This difference remained significant when the dataset was controlled for age, gender and body-mass index. In contrast, 0/21 of the arachidonic acid- and 0/4 of the dihomo-γ-linolenic acid, eicosapentaenoic acid or docosahenaenoic acid-derived oxylipins were higher in the patient samples at this level of significance. The area under the Receiver-Operator Characteristic (ROC) curve for 12,13-DiHOME was 0.91 (P<0.0001). Levels of four N-acylethanolamines were also analysed and found not to be significantly different between the controls and the patients at the level of P<0.0125 (<0.05/4). CONCLUSIONS/SIGNIFICANCE: It is concluded from this exploratory study that abnormal levels of linoleic acid-derived oxylipins are seen in blood serum from patients with Achilles tendinopathy. Given the ability of two of these, 9- and 13-HODE to activate transient receptor potential vanilloid 1, it is possible that these changes may contribute to the symptoms seen in Achilles tendinopathy.