The Midfoot Joint Complex (Foot Arch) Contributes to the Upper Body Position in Bipedal Walking and Coordinates With the Lower Limb Joints.

This study estimated the contribution of the midfoot joint complex (MJC) kinematics to the pelvis anterior-posterior positions during the stance phase of walking and investigated whether the MJC is functionally coordinated with the lower limb joints to maintain similar pelvic positions across steps. Hip, knee, ankle, and MJC sagittal angles were measured in 11 nondisabled participants during walking. The joints' contributions to pelvic positions were computed through equations derived from a link-segment model. Functional coordination across steps was identified when the MJC contribution to pelvic position varied and the summed contributions of other joints varied in the opposite direction (strong negative covariations [r ≤ -.7] in stance phase instants). We observed that the MJC plantarflexion (arch raising) during the midstance and late stance leads the pelvis backward, avoiding excessive forward displacement. The MJC was the second joint that contributed most to the pelvis positions (around 18% of all joints' contributions), after the ankle joint. The MJC and ankle were the joints that were most frequently coordinated with the other joints (≅70% of the stance phase duration). The findings suggest that the MJC is part of the kinematic chain that determines pelvis positions during walking and is functionally coordinated with the lower limb joints.

Influence of reduced passive ankle dorsiflexion range of motion on lower limb kinetics and stiffness during gait.

BACKGROUND: The ankle dorsiflexion range of motion (ADF-ROM) during single support phase allows elastic energy storage in the calcaneal tendon, contributing to advance the body forward. Reduced ADF-ROM may influence lower limb kinetics and stiffness. RESEARCH QUESTION: What is the influence of reduced passive ADF-ROM on lower limb internal moments and stiffness during gait? METHODS: Thirty-two participants, classified into two groups according to passive ADF-ROM (smaller than 10° and greater than 15°), were submitted to gait assessment at self-selected speed with a force platform and a three-dimensional motion analysis system. Statistical parametrical mapping (SPM) analyses were used to compare the lower limbs' internal moments between groups. Independent t-tests analyzed the differences between groups on lower limb stiffness during gait. RESULTS: The lower ADF-ROM group had greater knee flexor moment (terminal stance and push-off), greater ankle abductor (i.e., shank internal rotator) moment in terminal stance and greater knee internal rotator moment in mid to terminal stance. The lower ADF-ROM group also had higher lower limb stiffness during gait. SIGNIFICANCE: Individuals with reduced passive ADF-ROM had greater lower limb stiffness and adopted a gait pattern with increased knee and ankle moments, suggesting increased loading at these joints.

Trunk, Mass Grasp, Knee, and Hip Muscle Performance in CrossFit Participants: Reference Values According to Participants' Sex and Limb Dominance.

Background: CrossFit is characterized by a diverse range of exercises recruiting different muscles and requiring different muscle functions. A characterization of muscular performance parameters in this population is needed. Purpose: To determine reference values for various aspects of muscular performance of muscles of the trunk, thigh, hip, and mass grasp in CrossFit participants. Also, this investigation aimed to compare the strength measures between male and female CrossFit participants, as well as between dominant and non-dominant limbs. Design: Descriptive, Cross-sectional. Setting: Laboratory. Methods: Isometric strength of trunk extensors (TE) and mass grasp was measured with handheld and Jamar dynamometer respectively. An isokinetic dynamometer was used to assess the muscle performance of the knee flexors (KF) and extensors (KE) (at 60º/s and 300º/s), and hip flexors (HF), extensors (HE), and abductors (HA) (60º/s and 240º/s ). Reference values for torque, work, power, fatigue, flexor:extensor ratio for the knee (hamstring:quadriceps - H:Q) and hip (HF:HE) joints were calculated. The torque and work values were normalized by the body mass. Mixed multivariate and univariate analyses of variance and independent t-tests were used for statistical analyses to compare between sexes and limbs. Results: Participants included 111 individuals (58 males and 53 females) with at least one year of experience in CrossFit. Normative data are provided for the outcome variables. Males had greater values of muscular performance parameters than females in most variables (p<0.05). Also, the dominant limb had greater mass grasp strength (p<0.002), greater KE power at 60º/s (p=0.015), lower H:Q ratio at 60º/s (p=0.021) and 300º/s (p=0.008), and lower KE fatigue (p=0.002). Conclusion: This study provides reference values for the trunk extensors, mass grasp, knee, and hip muscle performance in male and female CrossFit practitioners. Their muscle performance profile was characterized by few inter-limb asymmetries, and males demonstrated greater muscular performance outcomes than females, even after normalization by body mass. These reference values can be used for comparisons in research and clinical settings. Level of Evidence: 3b.

Performance in field-tests and dynamic knee valgus in soccer players psychologically ready and not ready to return to sports after ACL reconstruction.

BACKGROUND: The objective was to compare the performance in field tests, dynamic knee valgus, knee function, and kinesiophobia of soccer players who were psychologically ready and not ready to return to unrestricted training or competitions after ACL reconstruction. METHODS: Thirty-five male soccer players who had undergone primary ACL reconstruction at least 6 months were divided based on the Anterior Cruciate Ligament Return to Sport after Injury (ACL-RSI) questionnaire score into ready (≥60) and not-ready (<60) groups. The modified Illinois change of direction test (MICODT) and reactive agility test (RAT) were used to impose the demand for directional change and reactive decision-making. We assessed the frontal plane knee projection angle (FPKPA) during a single-leg squat and distance in crossover hop test (CHD). In addition, we assessed kinesiophobia through the shortened version of the Tampa Scale of Kinesiophobia (TSK-11) and knee function using the International Knee Documentation Committee Subjective Knee Form (IKDC). Independent t-tests were used to compare the groups. RESULTS: The not-ready group had lower performance on the MICODT (effect size (ES) = -1.2; p < 0.001) and RAT (ES = -1.1; p = 0.004) tests and higher FPKPA (ES = 1.5; p < 0.001). In addition, they presented lower IKDC (ES = 3.1; p < 0.001) and higher TSK-11 (ES = -3.3; p < 0.001) scores. CONCLUSIONS: Physical and psychological deficits may persist in some individuals after rehabilitation. On-field tests and dynamic knee alignment evaluation should be included in the athlete evaluation before the decision-making about clearance to sports participation, especially in athletes who perceive themselves as psychologically not ready.

A new marker cluster anchored to the iliotibial band improves tracking of hip and thigh axial rotations.

Tracking hip and thigh axial rotation has limited accuracy due to the large soft tissue artifact. We proposed a tracking-markers cluster anchored to the prominent distal part of the iliotibial band (ITB) to improve thigh tracking. We investigated if the ITB cluster improves accuracy compared with a traditionally used thigh cluster. We also compared the hip kinematics obtained with these clusters during walking and step-down. Hip and thigh kinematics were assessed during a task of active internal-external rotation with the knee extended, in which the shank rotation is a reference due to smaller soft-tissue artifact. Errors of the hip and thigh axial rotations obtained with the thigh clusters compared to the shank cluster were computed as root-mean-square errors, which were compared by paired t-tests. The angular waveforms of this task were compared using the statistical parametric mapping (SPM). Additionally, the hip waveforms in all planes obtained with the thigh clusters were compared during walking and step-down, using Coefficients of Multiple Correlation (CMC) and SPM (α = 0.05 for all analyses). The ITB cluster errors were approximately 25 % smaller than the traditional cluster error (p < 0.001). ITB cluster errors were smaller at external rotation angles while the traditional cluster error was smaller at internal rotation angles (p < 0.001), although the clusters' waveforms were not significantly different (p ≥ 0.005). During walking and step-down, both clusters provided similar hip kinematics (CMC ≥ 0.75), but differences were observed in parts of the cycles (p ≤ 0.04). The findings suggest that the ITB cluster may be used in studies focused on hip axial rotation.

Association of Cycling Kinematics With Anterior Knee Pain in Mountain Bike Cyclists.

CONTEXT: Comfort and pain in cyclists are often discussed as a result of the posture on the bike, and bike fit, including motion analysis, is advocated as a strategy to minimize these conditions. The relationship between cycling kinematics, comfort, and pain is still debatable. OBJECTIVES: To investigate the association of ankle, knee, and trunk kinematics with the occurrence of anterior knee pain (AKP) in mountain bike cyclists. DESIGN: Cross-sectional study. METHODS: Fifty cross-country mountain bike cyclists (26 with AKP and 24 without AKP) had their pedaling kinematics assessed. Linear and angular data from trunk, hip, knee, ankle, and foot from cyclists with and without AKP were recorded using Retül motion analysis system. RESULTS: The binary logistic regression model showed that kinematic variables such as peak ankle plantar flexion, peak knee flexion, and forward trunk lean were significant predictors of AKP. Both larger peak plantar flexion and knee flexion decreased the probability of reporting AKP. On the other hand, larger forward trunk lean increased the probability of reporting AKP. CONCLUSIONS: Ankle, knee, and trunk sagittal kinematics may predict AKP in cross-country mountain bike cyclists, whereas hip, knee, and ankle alignment in the frontal plane showed no association with occurrence of AKP. In other words, cyclists with larger ankle plantar flexion and knee flexion are less likely to have AKP, whereas those with increased trunk forward lean are more likely to have AKP.

The Sleep Parameters of Paralympic Athletes: Characteristics and Assessment Instruments.

CONTEXT: Sleep serves many important functions for athletes, particularly in the processes of learning, memory, recovery, and cognition. OBJECTIVES: Define the sleep parameters of Paralympic athletes and identify the instruments used to assess and monitor sleep Paralympic athletes. EVIDENCE ACQUISITION: This systematic review was carried out based on the PRISMA guidelines. The survey was conducted in April 2020, the searches were carried out again in September 2021 to check whether there were new scientific publications in the area of sleep and Paralympic sport, searches were performed in the following databases: PubMed, Web of Science, Scopus, SPORTDiscus, Virtual Health Library (BIREME), and SciELO. This systematic review has included studies that investigated at least one of the following sleep parameters: total sleep time, sleep latency, sleep efficiency, number of awakenings, quality of sleep, daytime sleepiness, and chronotype; the participants were comprised of athletes with disabilities. Studies published at any time in English, Portuguese, and Spanish, were included. EVIDENCE SYNTHESIS: Data extraction and study selection were performed by 2 researchers independently, and a third author was consulted as necessary. The search returned a total of 407 studies. Following the screening based on exclusion and inclusion criteria, a total of 13 studies were considered. Paralympic athletes have a low amount (7.06 h) of sleep with poor quality and sleep latency (28.05 min), and 57.2% have daytime sleepiness, with the majority belonging to the indifferent chronotype (53, 5%). Moreover, 11 studies assess sleep using subjective instruments (questionnaires), and 2 studies used an objective instrument (actigraphy). CONCLUSIONS: Sleep disorders are common among Paralympic athletes, poor sleep quality and quantity, and high rates of daytime sleepiness. Subjective methods are most commonly used to assess sleep.

Effectiveness of multimodal circuit exercises for chronic musculoskeletal pain in older adults: A randomized controlled trial protocol.

Studies have shown that musculoskeletal pain is one of the most prevalent health conditions that affects many individuals worldwide. In older adults, persistent pain is a widely prevalent and a disabling condition of multiple contributing factors: physical, mental, and social. Consequently, their quality of life is hampered. We aimed to analyze the effectiveness of a multimodal circuit exercise program on chronic musculoskeletal pain and disabling in older adults. This is a randomized parallel study (two arms) with blinded outcome assessments. The participants' recruitment will be done by a non-probabilistic sampling resulting from invitations to Basic Health Units (BHU). The sample size estimation indicated 164 participants. Participants will be allocated, by means of a randomization process, to one of two groups (82 for each group): Experimental Group (multimodal circuit exercise) or Control Group (cycle of multidisciplinary lectures on pain and stretching exercise). All analyses will be processed using the RStudio software, with significance when a p-value of 2 tails is less than 5% (p<0.05). Statistical analysis will follow the intention to treat. Trial registration: ClinicalTrials.gov NCT04719130, January 20, 2021.

Interaction of scapular dyskinesis with hand dominance on three-dimensional scapular kinematics.

INTRODUCTION: This study aimed to evaluate the effect of scapular dyskinesis and its interaction with hand dominance and humerothoracic angles on three-dimensional scapular kinematics in asymptomatic individuals in all planes of arm motion. METHODS: Forty-five asymptomatic participants, seventeen men and twenty-eight women, were separated into two groups: with (n = 22) and without scapular dyskinesis (n = 23) according to the Yes/No classification. Scapular kinematic data of dominant and non-dominant sides in both groups were measured with an electromagnetic tracking device during arm elevation and lowering phases in scapular, frontal and sagittal planes. A linear mixed model of covariance adjusted for age and BMI was used, which included hand dominance (dominant and non-dominant), group (with and without scapular dyskinesis), angles (30°, 60°, 90°, and 120°), and the interaction effect (group × hand dominance × humerothoracic angle). RESULTS: There was a significant interaction effect on scapular anterior tilt and upward rotation in the sagittal plane, and for internal rotation and anterior tilt in the frontal and scapular planes. The effects of hand dominance on three-dimensional scapular kinematics, as increased anterior tilt, internal rotation and upward rotation, were greater in individuals without scapular dyskinesis. CONCLUSION: The effects of dominant side as increased upward rotation, internal rotation, and anterior tilt at higher humerothoracic angles for all planes of arm motion, were greater in individuals without scapular dyskinesis. Our findings may assist the scapular assessment which in individuals without scapular dyskinesis, bilaterally, possible between side differences in the scapular motions may be related to a dominance effect.

Interaction of hip and foot factors associated with anterior knee pain in mountain bikers.

OBJECTIVE: To investigate the association of interactions among trunk, hip, and foot/ankle musculoskeletal factors with the presence of anterior knee pain (AKP) in mountain bikers. DESIGN: Cross-sectional study. SETTING: Private clinical setting. PARTICIPANTS: Fifty professional and amateur cyclists, with and without AKP, were included. MAIN OUTCOME MEASURES: Bridge test with unilateral knee extension, hip stability isometric test (HipSIT), passive hip internal rotation (IR) range of motion (ROM), shank-forefoot alignment (SFA), and ankle dorsiflexion ROM were analyzed by classification and regression tree (CART) to identify interactions with AKP presence. A receiver-operating characteristic (ROC) curve verified accuracy of the model. To investigate strength of associations, prevalence ratios were calculated for each terminal node of the CART model. RESULTS: Interactions among passive hip IR ROM, HipSIT, ankle dorsiflexion ROM and SFA identified mountain bikers with and without AKP. The model achieved 76.9% sensitivity and 87.5% specificity. The area under the ROC curve was 0.86 (95% confidence interval: 0.75-0.97; standard error 0.05; p < 0.0001). CONCLUSION: Presence of AKP in mountain bike cyclists was associated with interactions among passive hip IR ROM, HipSIT and ankle dorsiflexion ROM captured by CART, indicating that the contribution of one factor depends on the presence of other factors.

Spatial-temporal parameters, pelvic and lower limb movements during gait in individuals with reduced passive ankle dorsiflexion.

BACKGROUND: Proper ankle dorsiflexion range of motion (ADF-ROM) allows the anterior roll of the tibia relative to the foot during the midstance phase of gait, which contributes to forward movement of the body. Individuals with reduced passive ADF-ROM may present altered movement patterns during gait due to an inefficient anterior tibial roll over the support foot during the stance phase. RESEARCH QUESTION: What is the influence of reduced passive ADF-ROM on the pelvic and lower limb movements and spatiotemporal parameters during gait? METHOD: Thirty-two participants divided into two groups according to the degree of passive ADF-ROM-less than 10° (lower ADF-ROM group) or greater than 15° (higher ADF-ROM group) -were subjected to gait assessment using a three-dimensional motion analysis system. Independent t-tests were used to compare the pelvic and lower limb movements and spatiotemporal gait parameters between the groups on this cross-sectional study. RESULTS: The lower ADF-ROM group had shorter step length, lower peak of pelvic ipsilateral rotation angle, and lower hip and knee maximum flexion angles in the stance phase (p < 0.05). In addition, the peaks of the ankle and forefoot-rearfoot dorsiflexion angles were smaller in the reduced ADF-ROM group (p < 0.05). The between-group differences presented effect sizes varying from moderate to large. SIGNIFICANCE: Individuals with reduced passive ADF-ROM presented reduced foot and ankle dorsiflexion, knee and hip flexion, and pelvis rotation movements and shorter step length during gait. However, no differences in foot pronation were noted between groups. Therefore, individuals with reduced passive ADF-ROM present alterations in the lower limb and pelvic movements during gait.

Comparison between the Rizzoli and Oxford foot models with independent and clustered tracking markers.

BACKGROUND: The Rizzoli Foot Model (RFM) and Oxford Foot Model (OFM) are used to analyze segmented foot kinematics with independent tracking markers. Alternatively, rigid marker clusters can be used to improve markers' visualization and facilitate analyzing shod gait. RESEARCH QUESTION: Are there differences in angles from the RFM and OFM, obtained with independent and clustered tracking markers, during the stance phase of walking? METHODS: Walking kinematics of 14 non-disabled participants (25.2 years (SD 2.8)) were measured at self-selected speed. Rearfoot-shank and forefoot-rearfoot angles were measured from two models with two tracking methods: RFM, OFM, RFM-cluster, and OFM-cluster. In RFM-cluster and OFM-cluster, the rearfoot and forefoot tracking markers were rigidly clustered, fixed on rods' tips attached to a metallic base. Statistical Parametric Mapping (SPM) One-Way Repeated Measures ANOVAs and SPM Paired t-tests were used to compare waveforms. Coefficients of Multiple Correlation (CMC) quantified the similarity between waveforms. One-way Repeated Measures ANOVAs were conducted to compare the ranges of motion (ROMs), and pre-planned contrasts investigated differences between the models and tracking methods. Intraclass Correlation Coefficients (ICC) were computed to verify the similarity between ROMs. RESULTS: Differences occurred mostly in small parts of the stance phase for the cluster vs. non-cluster comparisons and the RFM vs. OFM comparisons. ROMs were slightly different between the models and tracking methods in most comparisons. The curves (CMC ≥ 0.71) were highly similar between the models and tracking methods. The ROMs (ICC ≥ 0.67) were moderatetly to highly similar in most comparisons. RFM vs. RFM-cluster (forefoot-rearfoot angle - transverse plane), OFM vs. OFM-cluster and RFM vs. OFM (forefoot-rearfoot angle - frontal plane) were not similar (non-significant). SIGNIFICANCE: Rigid clusters are an alternative for tracking rearfoot-shank and forefoot-rearfoot angles during the stance phase of walking. However, specific differences should be considered to contrast results from different models and tracking methods.

Comparison of incidence, prevalence, severity and profile of health problems between male and female elite youth judokas: A 30-week prospective cohort study of 154 athletes.

OBJECTIVES: To describe and compare the incidence, prevalence, severity, and profile of injuries (acute and overuse) and illness between female and male youth elite judokas during 30 weeks of a sports season. DESIGN: Prospective cohort study. METHODS: A total of 154 elite youth judokas (83 males and 71 females) were assessed from January to August 2019 in a training period organized by the Brazilian Judo Confederation. We conducted a prospective 30-week follow-up study on acute and overuse injuries and illness among youth female and male judokas through the Oslo Sports Trauma Research Center questionnaire on health problems (OSTRC-H). Every week, the OSTRC-H was sent to all youth judokas electronically, starting in the first week of preseason. The incidence rate, prevalence, and severity of illnesses and acute and overuse injuries were compared between sexes using an independent t-test (variables with normal distribution) or Mann Whitney U test (variables with non-normal distribution) with α set a 0.05. RESULTS: Female and male judokas showed 16.96 and 16.57 injuries per 1000 athletic exposures, respectively (p = 0.383). Female judokas showed a higher average weekly prevalence of health problems (38.8%) than male judokas (29.0%). In addition, females had a greater prevalence of substantial health problems (p < 0.001), injuries (p < 0.001), and overuse injuries (p < 0.001) than males. CONCLUSION: There were no differences in the incidence rate of injuries between sexes. Youth female judokas showed a higher prevalence of all health problems than youth male judokas. For both sexes, the knee and shoulder were the most affected joints for acute and overuse injuries, respectively.

Prevalence of overuse injuries in athletes from individual and team sports: A systematic review with meta-analysis and GRADE recommendations.

BACKGROUND: Overuse injuries result from the cumulative process of repetitive microtrauma and overload on the musculoskeletal system, which causes tissue damage. Therefore, these injuries may have long-term negative consequences that decrease an athlete's performance. OBJECTIVE: To estimate the prevalence of overuse injuries in individual and team sports. METHODS: Searches on MEDLINE, EMBASE, SPORTDiscus, and CINAHL from the first registration to February 2021 and hand-searching identified studies investigating the prevalence of overuse injuries in athletes from individual and team sports. Meta-analysis was conducted and the GRADE system summarized the overall quality of evidence. This review was registered in PROSPERO (CRD42019135665). RESULTS: Seventeen studies were included and pooling of 24 704 participants (22 748 of individual sports and 1.956 of team sports). Data from point- and period-prevalence of overuse injuries in individual and team sports were obtained. Pooled period-prevalence of overuse injuries in individual and team sports was 42.0% (95% CI: 30.0, 55.0) and 33.0% (95% CI: 21.0, 49.0), respectively. Another four studies investigated point-prevalence. The overall quality of evidence for the period-prevalence was of moderate quality. Sensitivity analyses suggested that different joints based in individual and team sports tended to increase the estimated prevalence of overuse injuries. CONCLUSION: Athletes, clinicians, sport teams, and policymakers should be aware of the high prevalence of overuse injuries in athletes, especially, in athletes from individual sports. Current moderate-quality evidence shows that future high-quality studies are likely to impact on the estimated prevalence.

Spinal cord injury and work challenges: an analysis of paid work status and pathways of return to work in Brazil.

DESIGN: Retrospective cohort study. OBJECTIVES: To investigate paid work status and return to work (RTW) pathways after spinal cord injury (SCI). SETTING: SARAH Network of Rehabilitation Hospitals. METHODS: Participants were adults with traumatic SCI, aged between 18 and 60 years at the time of the injury, admitted between 2000 and 2017. In the first stage, socio-demographic, injury-related, and functional status data were collected from medical records. In the second stage, data on paid work, means of mobility, driving ability, return to study, ability to work, and satisfaction with the work status were collected through an online survey conducted between January and March 2020. RESULTS: A total of 154 participants were included in the sample. Of these, 90% were working at the time of SCI and 23% were engaged in paid work at the time of the study. Three RTW pathways were identified among those who were working at the time of the injury and: did not return to work (78%); returned to a different occupation (12%) and returned to the same occupation (9%). Number of post-injury complications, returning to study, good work ability, and satisfaction with the work status were predictors of paid work. The model's adjusted coefficient was 56.5% (p = 0.001). CONCLUSION: Working-age people with SCI who underwent rehabilitation in Brazil had a low rate of paid work. Fewer complications at the time of the injury, returning to study, good ability to work and greater satisfaction with the work status increased the likelihood of being engaged in paid work.

A novel single-leg squat test with speed and accuracy requirements: Reliability and validity in anterior cruciate ligament reconstructed individuals.

BACKGROUND: Some traditional single-leg squat tests focused on number of repetitions may not demand precise control of lower limb dynamic alignment, especially in the frontal and transverse planes. The primary objective of this study was to evaluate test-retest reliability and construct validity of a novel single-leg squat test - the 'precision-squat test' (PST) - designed to assess performance under varying task demands that can impact the execution of lower limb movements. A secondary objective was to investigate whether musculoskeletal factors predict performance in the PST in healthy individuals. METHODS: Thirty healthy participants were assessed to verify test-retest reliability. To verify the test's construct validity, we compared the performance of 21 anterior cruciate ligament reconstructed (ACLR) individuals and 21 matched controls. Finally, 36 healthy individuals were assessed to verify the musculoskeletal factors related to PST performance. All participants performed the PST: they executed single-leg squats while moving a laser pointer (attached to the thigh) between two targets. We varied target size and distance between targets to manipulate the task difficulty. RESULTS: Reliability of the PST was excellent at all demand levels (intraclass correlation coefficient (ICC)(3,2) > 0.93). Squat time increased under test conditions involving higher task difficulty (P < 0.001) and in ACLR individuals compared with age-matched controls (P < 0.05). Regression analyses revealed that reduced knee extensors and hip external rotators torques are related to increased squat time (P < 0.05). CONCLUSIONS: PST is a valid and reliable tool to assess performance of healthy and ACLR individuals. In addition, hip and knee strength are associated with performance during the test.

Reliability of a Low-Cost Assessment of Tibial Torsion and Transverse-Plane Posture of the Lower Limb and Pelvis Using a Smartphone Compass.

OBJECTIVES: The purpose of this study was to investigate intra- and interrater reliability and minimal detectable change (MDC) of clinical measures proposed to assess tibial torsion and the posture of the lower limbs and pelvis in the transverse plane. METHODS: Twenty-five able-bodied and asymptomatic participants (mean age 27 ± 4.03, 12 women) were assessed during relaxed standing with a compass application on a smartphone coupled to a caliper. Two trained examiners measured tibial torsion and angular postures of the pelvis, hip, femur, and tibia. Intraclass correlation coefficients (ICC) were used to investigate reliabilities, and MDCs were calculated. RESULTS: The results showed predominantly good-to-excellent reliability for the measures of the femur, hip, and tibia postures and tibial torsion (0.77 < ICC < 0.94), including some moderate-to-good reliability (0.65 < ICC < 0.75). The pelvic posture measure was predominantly moderate to good (0.55 < ICC < 0.86). MDCs have been reported (2.14°-7.86°) to assist clinicians in identifying postural changes that are within or outside the random measure variation. CONCLUSION: The use of a smartphone digital compass coupled to a caliper showed to be a reliable method to assess tibial torsion and transverse-plane postures of the lower limb and pelvis.

Normative reference values for handgrip strength, shoulder and ankle range of motion and upper-limb and lower limb stability for 137 youth judokas of both sexes.

OBJECTIVES: To provide reference values for handgrip strength, shoulder and ankle range of motion (ROM) and upper-limb and lower limb stability for youth judokas of both sexes and investigate the effects of sex and side dominance. DESIGN: Cross-sectional. METHODS: A total of 137 youth judokas from under-18 (n=60) and under-21 (n=77) categories of both sexes were assessed. Handgrip strength was assessed using a Jamar dynamometer, ankle ROM was measured by lunge test, shoulder ROM was assessed by an inclinometer and upper-limb and lower limb stability were assessed by the Closed Kinetic Chain Upper Extremity Stability Test and by the Modified Star Excursion Balance Test (mSEBT). RESULTS: In both categories, males had greater handgrip strength. In the under-18 category, the dominant side had greater handgrip strength, the non-dominant side of females had smaller shoulder external rotation ROM than the dominant side and also than both sides of males, and females had greater shoulder IR ROM. In the under-21 category, the dominant side of females had greater ankle dorsiflexion ROM than the dominant side of males, the dominant sides and females had greater shoulder ER ROM, and males had better performance in the mSEBT. CONCLUSIONS: This study provided reference values for handgrip strength, shoulder and ankle ROM, upper and lower limb stability for youth judokas, which can be used to guide assessment during preseason. Sex influenced on shoulder ER and IR ROM, handgrip strength and lower limb stability. In addition, side dominance influenced on shoulder ER ROM and on handgrip strength.

Normative data for hip strength, flexibility and stiffness in male soccer athletes and effect of age and limb dominance.

OBJECTIVE: The objective was to establish normative data for hip strength, flexibility, and stiffness in male soccer athletes and to investigate the effect of age and limb dominance on these variables. DESIGN: Cross-sectional. SETTING: Soccer team physical therapy department. PARTICIPANTS: A total of 293 asymptomatic male soccer athletes were assessed. Elite youth players aged 15-17 years and professional adult players aged 18-29 years old. MAIN OUTCOME MEASURES: Rectus femoris, iliopsoas, hamstring muscle flexibility, passive hip stiffness, and isometric hip strength were measured using a goniometer, inclinometer, and handheld dynamometer, respectively. Descriptive and mixed analyses of variance were used as statistical procedures. RESULTS: The dominant limb had lower iliopsoas (P = 0.010) and rectus femoris (P = 0.003) flexibility and higher external rotators torque compared to the non-dominant limb (P = 0.006) in both age groups. In adult athletes, the dominant limb had lower hip stiffness than the non-dominant limb (P = 0.002). Adults had higher hip external rotator torque than younger athletes (P < 0.0001). No differences were observed for hamstrings flexibility and hip extensors torque. CONCLUSION: This study provided normative data of hip strength, flexibility, and stiffness for youth and adult male soccer athletes. In addition, there were no clinically relevant inter-limb differences.

Comparison of Foot Kinematics and Foot Plantar Area and Pressure Among Five Different Closed Kinematic Tasks.

BACKGROUND: Different closed kinematic tasks may present different magnitudes of knee abduction, foot pronation, and foot plantar pressure and area. Although there are plenty of studies comparing knee abduction between different tasks, the literature lacks information regarding differences in foot pronation and foot plantar pressure and area. We compared foot angular displacement in the frontal plane and foot plantar pressure and area among five closed kinematic tasks. METHODS: Forefoot and rearfoot angular displacement and foot plantar pressure and area were collected in 30 participants while they performed the following tasks: stair descent, single-leg step down, single-leg squat, single-leg landing, and drop vertical jump. Repeated-measures analyses of variance were used to investigate differences between tasks with α = 0.05. RESULTS: Single-leg squat and stair descent had increased foot total plantar area compared with single-leg landing (P = .005 versus .027; effect size [ES] = 0.66), drop vertical jump (P = .001 versus P = .001; ES = 0.38), and single-leg step down (P = .01 versus P = .007; ES = 0.43). Single-leg landing and single-leg step down had greater foot total plantar area compared with drop vertical jump (P = .026 versus P = .014; ES = 0.54). There were differences also in rearfoot and midfoot plantar area and pressure and forefoot plantar pressure. CONCLUSIONS: Differences in foot-striking pattern, magnitude of ground reaction force, and task speed might explain these findings. Clinicians should consider these findings to improve decisions about tasks used during rehabilitation of patients with foot conditions.