Location of Measurement Matters: Unveiling Regional Dynamics and Sex Differences in Patellar Tendon Strain In Vivo.

Patellar tendinopathy is more prevalent in males versus female athletes and commonly presents in the medial region of the tendon. Separate measures of patellar tendon strain in the medial, central, and lateral regions of the tendon, however, have not been quantified. The purpose was to investigate the differences in tendon strain between the medial, lateral, and central regions of the patellar tendon in healthy men and women. Strain in the medial and lateral regions of the patellar tendon in healthy participants (10 males, 10 females) was evaluated using ultrasound during isometric quadriceps contractions at 20%, 40%, 60%, 80%, and 100% of maximum voluntary contraction (MVIC) in 60° and 90° of knee flexion. Central strain was also measured at 60% MVIC in 90° of knee flexion. Mixed models were used to determine strain between tendon regions and sex at 60% MVIC in 90° of knee flexion. Sequential modeling was used to fit region, sex, %MVIC, and angle to predict strain. The central region had less strain compared with both medial and lateral regions. The lateral region had higher strain compared with the medial region regardless of sex. Females had higher strain compared with males, regardless of region. Knee position did not influence tendon strain. Patellar tendon strain differs by region and sex. The varying prevalence between sex and in location of patellar tendinopathy may in part be explained by the unbalanced strains. Differential assessment of regional patellar tendon strain may be of importance for understanding injury risk and recovery with exercise.

Effects of insoles adapted in flip-flop sandals in patients with persistent plantar heel pain: A sham-controlled randomised trial.

OBJECTIVE: To evaluate the use of custom-made insoles adapted to flip-flops on pain intensity, foot function, and functional walking ability in individuals with persistent plantar heel pain in the short and medium term. DESIGN: Randomised controlled trial. SETTING: Flip-flop sandals in patients with persistent plantar heel pain. MAIN MEASURES: Participants (n = 80) were assessed at baseline, six and 12 weeks after the intervention, and 4 weeks post-intervention. RESULTS: For the primary outcomes, after 6 weeks of intervention, no between-group difference was observed in the intensity of morning pain or pain with walking, mean difference = -0.4 (95% confidence intervals = -1.5 to 0.8). Similarly, after 12 weeks of intervention, no between-group difference was observed in the intensity of morning pain or pain with walking, mean difference = -0.7 (95% confidence intervals = -1.9 to 0.6). Finally, at 4 weeks after the end of the intervention, there was no between-group difference in morning pain or pain on walking, mean difference = 0.01 (95% confidence intervals = -1.4 to 1.4). All differences and confidence intervals were smaller than the minimum clinically important difference for pain (2 points). There were no differences between the groups for the secondary outcomes. In addition, the mean differences were smaller than the minimum clinically important differences for pain intensity, foot function and functional walking ability. CONCLUSION: Custom-made insoles fitted to flip-flops did not differ from flip-flops with sham insoles in improving pain intensity, foot function and functional walking ability in people with persistent heel pain.Trial registration: ClinicalTrials.gov (Identifier: NCT04784598). Data of registration: 2023-01-20.

Effects of insoles adapted in flip-flop sandals in people with plantar fasciopathy: a randomized, double-blind clinical, controlled study.

OBJECTIVE: To evaluate the effects of insoles adapted into flip-flop sandals on pain and function in individuals with plantar fasciopathy (PF). DESIGN: Randomized, double-blind controlled study. SETTING: Physiotherapy clinic of the Faculty of Health Sciences of Trairi, Federal University of Rio Grande do Norte, Santa Cruz, Brazil. SUBJECTS: Sixty-six patients of both genders with PF were randomized into two groups: sandal insole group (SI; n = 34), which received a pair of custom flip-flop sandals with insoles covered with smooth synthetic leather; and plain sandal group (PS; n = 32), which received an identical pair of flip-flop sandals, but without the insoles. INTERVENTIONS: Patients were instructed to wear the flip-flops for 12 weeks for at least 4 hours/day. MAIN MEASURES: Pain (visual analogue scale-VAS) in the morning and at the end of the day were considered primary outcomes. Function (Foot Function Index-FFI and Foot and Ankle Ability Measure-FAAM) and functional capacity (6-minute walk test-6MWT) were considered secondary outcomes. The outcomes were evaluated at baseline and immediately after the intervention by a blind assessor. RESULTS: Between-group differences were observed in terms of morning pain (mean difference (MD) = -1.82 cm; 95% confidence interval (CI) = -3.3 to -0.3; P = 0.016) and function (MD = -0.10; 95% CI = -0.19 to -0.01; P = 0.023) after the interventions with the SI group showing superior improvements in comparison to the PS group. CONCLUSION: The use of insoles adapted in flip-flop sandals for 12 weeks was effective at improving pain and function in individuals with PF. LEVEL OF EVIDENCE: 1b.

Effects of exercise-based interventions on gluteal tendinopathy. Systematic review with meta-analysis.

The objective of this review was to evaluate the effect of exercise on pain intensity, function, and quality of life in individuals with gluteal tendinopathy. Searches were carried out in PUBMED, EMBASE, CINAHL, Cochrane Library, and PEDro databases. Randomized or quasi-randomized controlled trials were included. Five studies met the eligibility criteria, comparing exercise-based interventions with minimal interventions and/or corticosteroid injections. Three studies, involving 383 participants, were included in the quantitative analysis. Meta-analyses showed that exercise is superior to minimal intervention for function in short-term [mean difference (MD) = 10.24; 95% confidence interval (95%CI) = 5.98, 14.50) and long-term (MD = 6.54; 95%CI = 1.88, 11.21]). However, no difference was observed for quality of life in the short [standardized mean difference (SMD) = 0.33; 95%CI = -0.29, 0.94] and long-term (SMD = 0.11; 95%CI = -0.16, 0.37). The effect of exercise was no different from that of corticosteroid injections for pain intensity in the short (MD = 1.25; 95%CI = -3.56, 6.05) and long-term (MD = -1.37; 95%CI = -3.72, 0.98]). In conclusion, exercise is superior to minimal interventions for function in the short- and long-term in individuals with gluteal tendinopathy. Exercise and corticosteroid injections had similar effects on pain intensity, however, exercise showed a higher treatment success rate when compared to corticosteroid injections in this population. The GRADE analysis revealed that the certainty of the evidence ranges from low to very low, therefore, large high-quality randomized controlled trials are recommended.PROSPERO registration number: CRD42021242853.

Patellar Tendon Load Progression during Rehabilitation Exercises: Implications for the Treatment of Patellar Tendon Injuries.

PURPOSE: This study aimed to evaluate patellar tendon loading profiles (loading index, based on loading peak, loading impulse, and loading rate) of rehabilitation exercises to develop clinical guidelines to incrementally increase the rate and magnitude of patellar tendon loading during rehabilitation. METHODS: Twenty healthy adults (10 females/10 males, 25.9 ± 5.7 yr) performed 35 rehabilitation exercises, including different variations of squats, lunge, jumps, hops, landings, running, and sports specific tasks. Kinematic and kinetic data were collected, and a patellar tendon loading index was determined for each exercise using a weighted sum of loading peak, loading rate, and cumulative loading impulse. Then the exercises were ranked, according to the loading index, into tier 1 (loading index ≤0.33), tier 2 (0.33 < loading index <0.66), and tier 3 (loading index ≥0.66). RESULTS: The single-leg decline squat showed the highest loading index (0.747). Other tier 3 exercises included single-leg forward hop (0.666), single-leg countermovement jump (0.711), and running cut (0.725). The Spanish squat was categorized as a tier 2 exercise (0.563), as was running (0.612), double-leg countermovement jump (0.610), single-leg drop vertical jump (0.599), single-leg full squat (0.580), double-leg drop vertical jump (0.563), lunge (0.471), double-leg full squat (0.428), single-leg 60° squat (0.411), and Bulgarian squat (0.406). Tier 1 exercises included 20 cm step up (0.187), 20 cm step down (0.288), 30 cm step up (0.321), and double-leg 60° squat (0.224). CONCLUSIONS: Three patellar tendon loading tiers were established based on a combination of loading peak, loading impulse, and loading rate. Clinicians may use these loading tiers as a guide to progressively increase patellar tendon loading during the rehabilitation of patients with patellar tendon disorders and after anterior cruciate ligament reconstruction using the bone-patellar tendon-bone graft.

Therapeutic exercises in the clinical practice of Brazilian physical therapists in the management of rotator cuff tendinopathy: An online survey.

The objective of this study was to investigate how Brazilian physical therapists (PTs) use therapeutic exercises in the rehabilitation of individuals with rotator cuff (RC) tendinopathy. The study used an online survey with a mix of 62 open- and closed-ended questions divided into three sections: participant demographics, professional experience, and clinical practice in the rehabilitation of patients with RC tendinopathy. One hundred and fifty-nine Brazilian physical therapists completed the survey. Most of our sample recommended isometric exercises (69.9%) in the initial phase of rehabilitation and eccentric exercises (47.4%) in the advanced phase. However, there was a wide variability in determining the volume of exercises, particularly with isometric exercises. Most of our sample considered patient comfort and pain levels when adjusting exercise intensity, regardless of exercise type. The majority (48.40%) recommended weekly reassessment and modification of exercises. Additionally, despite pain being a key factor for discharge and the primary adverse effect of exercise, most of our sample would not discontinue exercises in case of pain during the early and late phases of rehabilitation. Despite the lack of consensus on some aspects, the clinical practice of our sample is in line with the current literature and practice in other countries. However, further research and implementation are crucial to enhance future rehabilitation outcomes, including exploring the exercise training volume, the safety and effectiveness of exercising with pain and identifying the optimal pain level for best results.

Rotator cuff isometric exercises in combination with scapular muscle strengthening and stretching in individuals with rotator cuff tendinopathy: A multiple-subject case report.

BACKGROUND AND PURPOSE: To assess the effects of a rehabilitation protocol of rotator cuff (RC) isometrics coupled with traditional shoulder exercises on patient-rated outcomes, muscle strength, and electromyographic activity in individuals with RC tendinopathy. METHODS: Eleven individuals (8 women and 3 men, 37.9 ± 5.6 years) with RC tendinopathy performed isometric RC exercises in combination with scapular muscle stretching and strengthening for 6 weeks. Treatment effects were assessed with patient-rated pain and shoulder function, isometric muscle strength, electromyographic activity during arm elevation and internal and external shoulder rotation, and pain during arm elevation before and at the end of the first session, and after 6 weeks of intervention. RESULTS: There were improvements in pain and shoulder function, increased isometric muscle strength for arm elevation and internal rotation, increased muscle activity of the infraspinatus and serratus anterior, and reduced pain during arm elevation after 6 weeks of intervention. DISCUSSION: This case report showed improvements on pain and function, increases on isometric strength of the shoulder and on electromyographic activity of the serratus anterior and infraspinatus muscles, as well as decreases on pain during arm elevation, after a 6-week intervention of RC isometric exercises associated with scapular muscle stretching and strengthening in patients with RC tendinopathy.

Effect of Symptom Duration on Injury Severity and Recovery in Patients With Achilles Tendinopathy.

Background: Achilles tendinopathy is a common overuse condition. Distinguishing between early- and late-stage tendinopathy may have implications on treatment decisions and recovery expectations. Purpose: To compare the effects of time and baseline measures of tendon health on outcomes among patients with varying symptom durations after 16 weeks of comprehensive exercise treatment. Study Design: Cohort study; Level of evidence, 3. Methods: Participants (N = 127) were categorized into 4 groups based on the number of months since symptom onset: ≤3 months (n = 24); between >3 and ≤6 months (n = 25); between >6 and ≤12 months (n = 18); or >12 months (n = 60). All participants received 16 weeks of standardized exercise therapy and pain-guided activity modification. Outcomes representing symptoms, lower extremity function, tendon structure, mechanical properties, psychological factors, and patient-related factors were assessed at baseline and at 8 and 16 weeks after the initiation of exercise therapy. Chi-square tests and 1-way analysis of variance were used to compare baseline measures between groups.Time, group, and interaction effects were evaluated using linear mixed models. Results: The mean age of the participants was 47.8 ± 12.6 years, 62 participants were women, and symptoms ranged from 2 weeks to 274 months. No significant differences were found among symptom duration groups at baseline for any measure of tendon health. At 16 weeks, all groups demonstrated improvements in symptoms, psychological factors, lower extremity function, and tendon structure, with no significant differences among the groups (P > .05). Conclusion: Symptom duration did not influence baseline measures of tendon health. Additionally, no differences were observed among the different symptom duration groups in response to 16 weeks of exercise therapy and pain-guided activity modification.

Patellofemoral Joint Loading Progression Across 35 Weightbearing Rehabilitation Exercises and Activities of Daily Living.

BACKGROUND: Exercises that provide progressive therapeutic loading are a central component of patellofemoral pain rehabilitation, but quantitative evidence on patellofemoral joint loading is scarce for a majority of common weightbearing rehabilitation exercises. PURPOSE: To define a loading index to quantify, compare, rank, and categorize overall loading levels in the patellofemoral joint across 35 types of weightbearing rehabilitation exercises and activities of daily living. STUDY DESIGN: Descriptive laboratory study. METHODS: Model-estimated knee flexion angles and extension moments based on motion capture and ground-reaction force data were used to quantify patellofemoral joint loading in 20 healthy participants who performed each exercise. A loading index was computed via a weighted sum of loading peak and cumulative loading impulse for each exercise. The 35 rehabilitation exercises and daily living activities were then ranked and categorized into low, moderate, and high "loading tiers" according to the loading index. RESULTS: Overall patellofemoral loading levels varied substantially across the exercises and activities, with loading peak ranging from 0.6 times body weight during walking to 8.2 times body weight during single-leg decline squat. Most rehabilitation exercises generated a moderate level of patellofemoral joint loading. Few weightbearing exercises provided low-level loading that resembled walking or high-level loading with both high magnitude and duration. Exercises with high knee flexion tended to generate higher patellofemoral joint loading compared with high-intensity exercises. CONCLUSION: This study quantified patellofemoral joint loading across a large collection of weightbearing exercises in the same cohort. CLINICAL RELEVANCE: The visualized loading index ranks and modifiable worksheet may assist clinicians in planning patient-specific exercise programs for patellofemoral pain rehabilitation.

Markerless motion capture estimates of lower extremity kinematics and kinetics are comparable to marker-based across 8 movements.

Motion analysis is essential for assessing in-vivo human biomechanics. Marker-based motion capture is the standard to analyze human motion, but the inherent inaccuracy and practical challenges limit its utility in large-scale and real-world applications. Markerless motion capture has shown promise to overcome these practical barriers. However, its fidelity in quantifying joint kinematics and kinetics has not been verified across multiple common human movements. In this study, we concurrently captured marker-based and markerless motion data on 10 healthy study participants performing 8 daily living and exercise movements. We calculated the correlation (Rxy) and root-mean-square difference (RMSD) between markerless and marker-based estimates of ankle dorsi-plantarflexion, knee flexion, and three-dimensional hip kinematics (angles) and kinetics (moments) during each movement. Estimates from markerless motion capture matched closely with marker-based in ankle and knee joint angles (Rxy ≥ 0.877, RMSD ≤ 5.9°) and moments (Rxy ≥ 0.934, RMSD ≤ 2.66 % height × weight). High outcome comparability means the practical benefits of markerless motion capture can simplify experiments and facilitate large-scale analyses. Hip angles and moments demonstrated more differences between the two systems (RMSD: 6.7-15.9° and up to 7.15 % height × weight), especially during rapid movements such as running. Markerless motion capture appears to improve the accuracy of hip-related measures, yet more research is needed for validation. We encourage the biomechanics community to continue verifying, validating, and establishing best practices for markerless motion capture, which holds exciting potential to advance collaborative biomechanical research and expand real-world assessments needed for clinical translation.

Challenging the assumption of uniformity in patellar tendon structure: Regional patellar tendon morphology and mechanical properties in vivo.

Patellar tendons are assumed to be uniform in morphology and mechanical properties despite a higher prevalence of tendinopathies observed in the medial region. The purpose of this study was to compare the thickness, length, viscosity, and shear modulus of the medial, central, and lateral regions of healthy patellar tendons of young males and females in vivo. B-mode ultrasound and continuous shear wave elastography were performed on 35 patellar tendons (17 females, 18 males) over three regions of interest. A linear mixed-effects model (α = 0.05) was used to determine differences between the three regions and sexes followed by pairwise comparisons for significant findings. The lateral region (mean [95% confidence interval] = 0.34 [0.31-0.37] cm) was thinner compared with the medial (0.41 [0.39-0.44] cm, p < 0.001), and central (0.41 [0.39-0.44] cm, p < 0.001) regions regardless of sex. Viscosity was lower in the lateral (19.8 [16.9-22.7] Pa-s) versus medial region (27.4 [24.7-30.2] Pa-s, p = 0.001). Length had a region-by-sex interaction (p = 0.003) characterized by a longer lateral (4.83 [4.54-5.13] cm) versus medial (4.42 [4.12-4.72] cm) region in males (p < 0.001), but not females (p = 0.992). Shear modulus was uniform between regions and sexes. The thinner, and less viscous lateral patellar tendon may reflect the lower load the tendon experiences explaining the differences in regional prevalence of developing tendon pathology. Statement of Clinical Significance: Healthy patellar tendons are not uniform in morphology or mechanical properties. Considering regional tendon properties may help guide targeted interventions for patellar tendon pathologies.

Stability, performance and upper and lower extremities range of motion in elite beach handball athletes: A cross sectional study.

Although beach handball is a popular sport worldwide, information about the functional profile in elite athletes are lacking. This study generate a descriptive profile of stability, performance and upper and lower extremities ROM in elite beach handball athletes. Secondary proposals were to compare these outcome measures between sexes and sides, and to report the frequency of athletes "at risk" according to cutoff values for shoulder ROM and dynamic postural stability of the lower extremities. Twenty-eight (n = 16 males, 28.7 ± 5.3 years; n = 12 females, 27.5 ± 5.5 years) elite beach handball athletes were tested. Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), single hop test, modified Star Excursion Balance Test (mSEBT) and passive shoulder, hip and ankle dorsiflexion ROM were assessed. Male athletes presented greater reach distance in the anterior direction [P < .0001; Mean Difference (MD): 36%] and lower reach distance in the posteromedial direction (P < .0001; MD: -29.7%) than female athletes in the mSEBT. Bilateral differences were observed for male athletes during the mSEBT, with the dominant stance limb obtaining a smaller reach distance in the anterior direction (P < .01; MD: -38.3%) and greater reach distance in the posteromedial direction (P < .0001; MD: 30.8%). Male athletes had less upper and lower extremities ROM and reached a smaller normalized single hop distance than female athletes. Most athletes presented mSEBT asymmetries and shoulder ROM deficits which have been shown to increase injury risk. Dynamic postural stability adaptations are present in elite beach handball athletes of both sexes, with more pronounced upper and lower extremity flexibility deficits in male athletes.

Are static foot posture and ankle dorsiflexion range of motion associated with Achilles tendinopathy? A cross-sectional study.

BACKGROUND: Subtalar hyperpronation and ankle dorsiflexion restriction have been theoretically associated with Achilles tendinopathy (AT). However, evidence to support these associations is lacking. OBJECTIVES: To compare foot alignment and ankle dorsiflexion range of motion (ROM) between the symptomatic and non-symptomatic limbs of individuals with unilateral AT. And to verify whether differences exist between individuals with symptomatic pronated feet and individuals with symptomatic neutral/supinated feet in terms of tendon pain, structure, and symptom severity. METHODS: Sixty-three participants with unilateral AT underwent a bilateral evaluation of pain during tendon palpation, symptom severity, tendon thickening, tendon neovascularization, ankle dorsiflexion ROM, and foot posture alignment [foot posture index (FPI), navicular drop, navicular drift, and longitudinal arch angle (LAA)]. Side and group comparisons were made using t-tests and correlations were evaluated using the Pearson test. RESULTS: There were no differences between the symptomatic and non-symptomatic limbs regarding foot posture alignment. Specifically, non-significant negligible differences were observed between limbs regarding FPI [mean difference (MD)=-0.23; 95% confidence interval (CI)=-0.70, 0.25), navicular drop (MD=0.58 mm; 95%CI=-0.25, 1.43), navicular drift (MD=0.16 mm; 95%CI=-0.77, 1.09), and LAA (MD=0.30º; 95%CI=-1.74, 2.34). There was no difference between limbs regarding ankle dorsiflexion ROM. However, lower ankle dorsiflexion was associated with worse symptom severity (r = 0.223). Finally, no difference was observed between individuals with symptomatic pronated feet and individuals with symptomatic neutral/supinated feet in terms of tendon pain or structure. CONCLUSIONS: Static foot alignment measures do not seem to be clinically relevant in patients with AT. Smaller ankle dorsiflexion ROM, however, was associated with greater symptom severity in this population.

Association of Ankle Dorsiflexion and Landing Forces in Jumping Athletes.

BACKGROUND: Dorsiflexion range of motion restriction has been associated with patellar tendinopathy, but the mechanisms of how dorsiflexion restriction could contribute to knee overload remain unknown. HYPOTHESIS: Peak ankle dorsiflexion and ankle dorsiflexion excursion are negatively associated with peak vertical ground-reaction force (vGRF) and loading rate, and with peak patellar tendon force and loading rate, and positively associated with peak ankle plantar flexor moment. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 4. METHODS: Kinematic and kinetic data of 26 healthy recreational jumping athletes were measured during a single-leg drop vertical jump. Pearson's correlation coefficients were calculated to establish the association between peak ankle dorsiflexion and ankle dorsiflexion excursion with peak vGRF and vGRF loading rate, with peak patellar tendon force and patellar tendon force loading rate, and with peak ankle plantar flexor moment. RESULTS: Ankle dorsiflexion excursion negatively correlated with peak vGRF loading rate (r = -0.49; P = 0.011) and positively correlated with peak ankle flexor plantar moment (r = 0.52; P = 0.006). In addition, there was a positive correlation between peak ankle dorsiflexion and peak vGRF (r = 0.39; P = 0.05). CONCLUSION: Ankle kinematics are associated with vGRF loading rate, ankle flexor plantar moment and peak vGRF influencing knee loads, but no association was observed between ankle kinematics and patellar tendon loads. CLINICAL RELEVANCE: These results suggest that increasing ankle dorsiflexion excursion may be an important strategy to reduce lower limb loads during landings but should not be viewed as the main factor for reducing patellar tendon force.

Simple verbal instructions are able to improve quality of movement during the lateral step-down test in healthy females.

INTRODUCTION: Altered movement patterns during weight-bearing activities have been associated with knee injuries and can be clinically assessed using the lateral step-down test (LSD). It is possible that verbal feedback can improve movement patterns, but it remains unknown whether verbal feedback can improve movement quality during the LSD. PURPOSE: To investigate whether verbal feedback can immediately improve visual movement quality and trunk, pelvis and lower limb kinematics in healthy females during the LSD. METHODS: 34 healthy females were assessed visually and with 3D kinematics while performing the LSD. Participants were divided into Good Movement Group (GG; n = 18) and Poor Movement Group (PG; n = 16) based on the LSD score. The feedback involved verbal instructions aimed at improving trunk, pelvis, hip and knee alignment during the test. Lower limb flexibility and strength were assessed for group comparisons and to investigate associations between all variables. Data analyses were performed using repeated-measures two-way ANOVAs and Spearman correlation tests. RESULTS: Feedback immediately improved movement quality, especially in participants of the GG [mean difference (MD) = 2.2 points; P < 0.001]. The PG showed greater pelvic drop (MD = 5.1°; P = 0.012), greater hip adduction (MD = 5.4°; P = 0.028) and less hip flexion (MD = 8.4°; P = 0.016) than the GG. Quality of movement had positive correlations with pelvic drop (r = 0.39; P = 0.02), hip adduction (r = 0.45; P = 0.01) and hip flexion (r = 0.49; P < 0.01) kinematics. CONCLUSIONS: Verbal feedback improved movement quality during the LSD in healthy females. Females with worst movement quality showed greater pelvic drop and hip adduction, which are often found in individuals with knee disorders.

Dry cupping therapy is not superior to sham cupping to improve clinical outcomes in people with non-specific chronic low back pain: a randomised trial.

QUESTION: What are the effects of dry cupping on pain intensity, physical function, functional mobility, trunk range of motion, perceived overall effect, quality of life, psychological symptoms and medication use in individuals with chronic non-specific low back pain? DESIGN: Randomised controlled trial with concealed allocation, intention-to-treat analysis and blinding of participants and assessors. PARTICIPANTS: Ninety participants with chronic non-specific low back pain. INTERVENTIONS: The experimental group (n = 45) received dry cupping therapy, with cups bilaterally positioned parallel to the L1 to L5 vertebrae. The control group (n = 45) received sham cupping therapy. The interventions were applied once a week for 8 weeks. OUTCOME MEASURES: Participants were assessed before and after the first treatment session, and after 4 and 8 weeks of intervention. The primary outcome was pain intensity, measured with the numerical pain scale at rest, during fast walking and during trunk flexion. Secondary outcomes were physical function, functional mobility, trunk range of motion, perceived overall effect, quality of life, psychological symptoms and medication use. RESULTS: On a 0-to-10 scale, the between-group difference in pain severity at rest was negligible: MD 0.0 (95% CI -0.9 to 1.0) immediately after the first treatment, 0.4 (95% CI -0.5 to 1.5) at 4 weeks and 0.6 (95% CI -0.4 to 1.6) at 8 weeks. Similar negligible effects were observed on pain severity during fast walking or trunk flexion. Negligible effects were also found on physical function, functional mobility and perceived overall effect, where mean estimates and their confidence intervals all excluded worthwhile effects. No worthwhile benefits could be confirmed for any of the remaining secondary outcomes. CONCLUSION: Dry cupping therapy was not superior to sham cupping for improving pain, physical function, mobility, quality of life, psychological symptoms or medication use in people with non-specific chronic low back pain. PROTOCOL REGISTRATION NUMBER: NCT03909672.

Injury Profile in a Brazilian First-Division Youth Soccer Team: A Prospective Study.

CONTEXT: Despite the popularity of soccer at the male first-division youth level, data on the incidence of injuries in Brazil are limited. OBJECTIVE: To prospectively study the injury profile of male first-division youth soccer players during 1 season (January to December 2017). DESIGN: Descriptive epidemiology study. SETTING: Data compiled at a youth soccer academy. PATIENTS OR OTHER PARTICIPANTS: The study involved 228 players between 10 and 20 years old from a first-division Brazilian soccer academy. MAIN OUTCOME MEASURE(S): Injury incidence rate was reported as the number of injuries divided by overall exposure (training and match hours) multiplied by 1000. The rate ratio (injury incidence rate during matches in relation to training) was also calculated. Time-loss injuries (ie, physical complaints sustained during soccer matches or training that resulted in a player being unable to take part in soccer training or match play) during the season were recorded. RESULTS: A total of 187 injuries were documented in 122 players (65.2%). During the season, 100 389 hours of exposure (5995 hours of match play and 94 394 of training) were registered. The overall injury incidence rate was 1.86 per 1000 hours. In total, 4792 days were lost from soccer activities. The majority of injuries were noncontact thigh muscle disorders and ankle sprains. Injury incidence was greater in matches than in training, and the oldest age group (under 20 years old) had the highest injury incidence rate in matches, while the under 17-year-old group had the highest injury incidence rate in training sessions (22.48 and 3.05 per 1000 hours, respectively). CONCLUSIONS: Muscle injury incidence rates observed among Brazilian soccer athletes under 20 years old were similar to those reported in professional players. Preventive measures are recommended to reduce injury rates. Additionally, the number of injuries incurred during training was high compared with match play, and training programs need to be assessed so that injury prevention can be improved.

Y-Balance Test Asymmetry and Frontal Plane Knee Projection Angle During Single-leg squat as Predictors of Patellofemoral Pain in Male Military Recruits.

OBJECTIVES: Investigate prospectively whether dynamic balance and frontal plane knee projection angle (FPKPA) are risk factors for the development of patellofemoral pain (PFP) in male military recruits. STUDY DESIGN: Prospective cohort. SETTING: Military training center. PARTICIPANTS: 135 male military recruits were followed prospectively for six weeks and the incidence of PFP was documented. MAIN OUTCOMES: Baseline measures of the Y-Balance test (YBT) and two-dimensional FPKPA during single-leg squatting were recorded. Mann-Whitney U tests and logistic regression analysis were utilized to identify possible variables associated with the development of PFP. RESULTS: A total of 14 male recruits developed PFP during the follow up period. The PFP group had significantly greater asymmetry on the YBT posterolateral direction (mean difference = 3.44 ± 0.57 cm; 95% Confidence Interval [CI] = 2.38-4.51 cm) and greater FPKPA during single-leg squat (mean difference = 5.55°±1.78°; [CI] = 1.81-9.28°) at baseline when compared to controls. Binary logistic regression models revealed that YBT posterolateral asymmetry ≥4.08 cm (Nagelkerke R2 = 0.304; X2 = 21.63; p < 0.001; OR = 5.46; [CI] = 4.47-8.06) and FPKPA ≥ 4.81° (Nagelkerke R2 = 0.249; X2 = 17.46; p < 0.001; OR = 4.65; [CI] = 3.32-9.06) were significantly associated with PFP. CONCLUSIONS: Male military recruits with greater asymmetry on the YBT posterolateral direction and FPKPA were at a greater risk of developing PFP.

Effects of dry cupping on pain, function and quality of life in women with knee osteoarthritis: a protocol for a sham-controlled randomised trial.

INTRODUCTION: Knee osteoarthritis (KOA) is the most common cause of pain and disability worldwide. Dry cupping has been used as non-pharmacological approach to control pain and improve physical function. However, there is a lack of high-quality scientific evidence regarding its effects on this condition. This protocol describes a sham-controlled, randomised and simple blind study that aims to evaluate the effect of dry cupping on pain, function and quality of life in women with KOA. METHODS AND ANALYSIS: Sixty-two women diagnosed with KOA, based on American College of Rheumatology clinical criteria, and aged from 50 to 75 years, will be randomly distributed into two groups (31 per group): real and sham dry cupping. Both applications will occur with acrylic cups around the knee. The intervention will last 15 min, two times a week over six consecutive weeks, for a total of 12 sessions. Both groups will be assessed at four different times: before the intervention (T0), after 3 weeks intervention (T3), at the end of the protocol (T6) and 4 weeks after the interventions (follow-up: T10). The primary outcome will be pain intensity (Numerical Pain Rating Scale), and secondary outcomes will be knee-related health status (Western Ontario and McMaster Universities Osteoarthritis Index), functional capacity (8-step stair climb test, 40-metre fast-paced walk test and 30-second chair stand test), quality of life (Short-Form 36) and global perceived effect. ETHICS AND DISSEMINATION: This protocol was approved by the UFRN/FACISA Ethics Committee (number 3.737.688). The study results will be disseminated to the participants and submitted to a peer-reviewed journal and scientific meetings. TRIAL REGISTRATION NUMBER: NCT04331158.

Relationship between the architecture and function of ankle plantar flexors with Achilles tendon morphology in ballet dancers.

Achilles tendinopathy is the most frequent foot overuse injury in ballet dancers and knowledge of clinically modifiable factors related to tendon structure in a population at risk, such as ballet dancers, would be important for the development of preventive programs. Therefore, the present study aimed to assess relationships of gastrocnemius muscle architecture and ankle plantar flexors function with Achilles tendon morphology in ballet dancers. Fifty-four measures from 27 ballet dancers were collected. Tendon morphology (thickness, echogenicity, hypoechoic areas and neovascularisation) and muscle architecture (thickness, pennation angle and fascicle length) were evaluated using ultrasonography; ankle plantar flexors torque was evaluated using hand-held dynamometry, flexibility was evaluated in maximal weight-bearing ankle dorsiflexion position using inclinometer, and endurance was evaluated using the heel rise test. Ankle plantar flexors torque and medial gastrocnemius muscle architecture (thickness, pennation angle and fascicle length) are associated with Achilles tendon thickness in ballet dancers (r2 = 0.24, p = 0.008). Ankle plantar flexors torque and medial gastrocnemius muscle fascicle length are also associated with the echogenicity of the Achilles tendon (r2 = 0.13, p = 0.03). These findings call attention to the potential importance of ankle plantar flexors muscle force in healthy ballet dancers for the prevention of alterations in Achilles tendon structure.