Load Carriage During Walking Increases Dynamic Stiffness at Distal Lower Limb Joints.

The addition of a load during walking requires changes in the movement pattern. The investigation of the dynamic joint stiffness behavior may help to understand the lower limb joints' contribution to these changes. This study aimed to investigate the dynamic stiffness of lower limb joints in response to the increased load carried while walking. Thirteen participants walked in two conditions: unloaded (an empty backpack) and loaded (the same backpack plus added mass corresponding to 30% of body mass). Dynamic stiffness was calculated as the linear slope of the regression line on the moment-angle curve during the power absorption phases of the ankle, knee, and hip in the sagittal plane. The results showed that ankle (P = .002) and knee (P < .001) increased their dynamic stiffness during loaded walking compared with unloaded, but no difference was observed at the hip (P = .332). The dynamic stiffness changes were different among joints (P < .001): ankle and knee changes were not different (P < .992), but they had a greater change than hip (P < .001). The nonuniform increases in lower limb joint dynamic stiffness suggest that the ankle and knee are critical joints to deal with the extra loading.

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.

Effects of lower-limb extensors' neuromuscular fatigue on the regularity of running movements: a crossover study.

Neuromuscular fatigue (NMF) reduces the musculoskeletal system's ability to produce force during activities like running. Analysis of motor behaviour's regularity may identify motor system deficits caused by fatigue. The present study investigated whether the NMF of lower limb extensors alters the regularity of running movement and whether this possible effect remains over time. Crossover study with two randomised conditions: NMF and control. Twelve healthy young males participated in this study. Hip, knee, and ankle angles (sagittal plane) and centre of mass (CoM) linear accelerations were assessed during treadmill running at self-selected speed in four assessment conditions: Baseline (pre-NMF), and after NMF (NMF condition) or after rest (control), at the 1st (Time_1), 10th (Time_10) and 20th (Time_20) minutes. Kinematics regularity was measured as Sample Entropy. Repeated measures ANOVAs were used (α = 0.05). NMF reduced regularity of lower limb joints during running, and these effects remained up to 20 minutes. No changes were observed in the CoM accelerations' regularity. The regularity reductions may be an adaptive solution for the motor system to maintain the task performance. The measure of regularity of the lower limb joints' motion is sensitive to NMF and can identify states with deficits in muscles' force production capacity in running.

Effect of sleep deprivation on postural control and dynamic stability in healthy young adults.

BACKGROUND: Postural control results from non-linear interactions of multiple neuromusculoskeletal elements and contextual factors. The use of non-linear analyses that consider the temporal evolution of postural adjustments, such as sample entropy, could inform about the changes in postural control due to contextual disturbances such as sleep deprivation. RESEARCH QUESTION: What are the effects of sleep deprivation on static postural control and dynamic stability in healthy young adults? METHODS: A quasi-experimental study was performed with 17 healthy young males submitted to 24 h of monitored sleep deprivation. The postural control was measured using sample entropy, area, and total average velocity of the center of pressure on a force platform. The dynamic stability was measured using the Modified Star Excursion Balance Test (SEBTm) composite score for each lower limb. Repeated-measures analysis of variance (baseline × 12 h × 15 h × 18 h × 21 h × 24 h of sleep deprivation) verified the effect of sleep deprivation in the postural control variables. Paired t-test compared the composite score of the SEBTm between baseline and 24 h sleep deprivation. RESULTS: Sample entropy decreased after 18 h of sleep deprivation (p = 0.032) and 24 h of sleep deprivation (p = 0.001). Despite the significant main effect for the area (p = 0.012) and speed (p = 0.007) of the center of pressure, no pairwise differences were identified in the post hoc analysis. The non-dominant lower limb SEBTm composite score was reduced after 24 h of sleep deprivation (p = 0.033), and no difference was observed in the dominant limb. SIGNIFICANCE: Sleep deprivation reduced the adaptability in static postural control and dynamic stability of the non-dominant lower limb of healthy young male adults. Sample entropy seemed more sensitive to capture the effects of sleep deprivation than the classical postural control variables.

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.

Effects of sex and walking speed on the dynamic stiffness of lower limb joints.

Fast walking may require a non-uniform change of dynamic stiffness among lower limb joints to deal with this daily task's demands. The change of dynamic joint stiffness may be distinct between females and males. This study aimed to test for differences in dynamic stiffness among lower limb joints in response to increased walking speed in males and females. Thirty-five participants walked in two randomized conditions: self-selected speed and fast speed (25% greater than the self-selected speed). Dynamic stiffnesses of the ankle, knee, and hip were calculated as the linear slope of the moment-angle curve's regression line during their major power absorption phase of the walking cycle. The comparison between conditions showed that the knee (p < 0.001) and hip (p = 0.031) increased their stiffness at the fast compared to self-selected speed. Ankle stiffness was not different between conditions (p = 0.818). The comparison among joints across speeds showed that the knee had a greater increase than the ankle (p = 0.001) and hip (p < 0.001), with no difference between ankle and hip (p = 0.081). The sex of the participant influenced only the ankle stiffness, in which males had greater stiffness than females (p = 0.008). These findings demonstrated that the lower limb joints changed their dynamic stiffness differently, and only the ankle stiffness was influenced by sex. The non-uniform adjustments of stiffness may provide the necessary stability and allow the individual to deal with greater demand for walking fast.

The effects of small and large varus alignment of the foot-ankle complex on lower limb kinematics and kinetics during walking: A cross-sectional study.

BACKGROUND: The alignment of the foot-ankle complex may influence the kinematics and kinetics of the entire lower limb during walking. OBJECTIVES: This study investigated the effect of different magnitudes of varus alignment of the foot-ankle complex (small versus large) on the kinematics and kinetics of foot, ankle, knee, and hip in the frontal and transverse planes during walking. DESIGN: Cross-sectional study. METHOD: Foot-ankle complex alignment in the frontal plane was measured as the angle between the metatarsal heads and the inferior edge of the examination table, measured with the volunteer in prone maintaining the ankle at 0° in the sagittal plane. The participants (n = 28) were divided into two groups according to their alignment angles. The first group had values equal to or inferior to the 45 percentile, and the second group had values equal to or above the 55 percentile. The lower limb kinematics and kinetics were evaluated with the participant walking at self-select speed in an instrumented treadmill. RESULTS: The group of large varus alignment showed significantly higher (p < 0.03) forefoot inversion angle at initial contact, amplitude of rearfoot-shank eversion, and peak of inversion ankle moment. There were no differences (p > 0.05) between the groups for knee and hip amplitudes and moments in the frontal and transverse planes. The durations of rearfoot-shank eversion, knee abduction, knee medial rotation, hip adduction, and hip medial rotation were not different between groups (p > 0.05). CONCLUSION: Large varus alignment of the foot-ankle complex may increase the magnitude of foot pronation and ankle inversion moment during walking.

Effects of baby walker use on the development of gait by typically developing toddlers.

BACKGROUND: Decisions about the use of baby walker are in part predicated on caregivers´ beliefs about its effect on gait development. The actual effects of baby walkers, however, have not been established. RESEARCH QUESTION: What are the effects of the use of baby walker prior to gait onset on age of acquisition of this milestone and on early walking kinematics? METHODS: Thirty-two toddlers, 16 in the baby walker group (BWG) and 16 in the non-users group (BWNG), were evaluated in the week of gait acquisition and monthly up to six months after this event. Spatial and temporal gait parameters and lower limb kinematics during walking were assessed using a tridimensional motion analysis system. An independent t-test compared age of gait acquisition between groups. A mixed ANOVA examined the effects of group, moment of assessment and the group x moment of assessment interaction effect on the amplitude of joint motions during walking and on spatial and temporal gait parameters. RESULTS: The age of gait acquisition was not different between groups. BWG had lower gait speed (specifically in the first, third, fourth, and fifth months after gait acquisition) and longer duration of stance and swing phases than BWNG. Additionally, BWG had smaller knee amplitude and greater hip amplitude in sagittal plane than BWNG in the week of gait acquisition. SIGNIFICANCE: The results demonstrated that there is no delay in the age of gait acquisition, but there are differences in kinematics. These results can contribute to evidence-based recommendations by health care professionals about the use of baby walker by toddlers during emergence and early development of gait.

Effects of a foot orthosis inspired by the concept of a twisted osteoligamentous plate on the kinematics of foot-ankle complex during walking: A proof of concept.

It has been suggested that the foot acts as a twisted osteoligamentous plate to control pronation and facilitate supination during walking. The aim of this study was to investigate the effect of an orthosis inspired by the concept of a foot's twisted osteoligamentous plate on the kinematics of foot-ankle complex. Thirty-five subjects underwent a kinematic assessment of the foot-ankle complex during walking using three different orthoses: (1) Twisted Plate Spring (TPS) orthosis: inspired by the concept of a twisted osteoligamentous plate shape and made with a spring-like material (carbon fiber); (2) Flat orthosis: control orthosis made of a non-elastic material with a non-inclined surface; and (3) Rigid orthosis: control orthosis made of a non-elastic material, with the same shape of the TPS. Repeated measures analyses of variance demonstrated that the TPS reduced the duration and magnitude of rearfoot eversion (p ≤ 0.03), increased rearfoot inversion relative to shank (p < 0.01), increased forefoot eversion relative to rearfoot (p < 0.01), and increased peak of plantar flexion of forefoot relative to rearfoot during the propulsive phase (p = 0.01) compared to Flat orthosis. The effects of the TPS were different from the Rigid orthosis, demonstrating that, alongside shape, material properties were a determinant factor for the obtained results. The findings of this study help clarify the role of a mechanism similar to a twisted osteoligamentous plate on controlling foot pronation and facilitating supination during the stance phase of walking.

Passive stiffness of the ankle and plantar flexor muscle performance after Achilles tendon repair: a cross-sectional study.

BACKGROUND: Deficits in ankle muscle strength and ankle stiffness may be present in those subjects who underwent surgical treatment for an Achilles tendon rupture. The presence of these long-term deficits may contribute to a lower performance during daily activities and may be linked to future injuries. OBJECTIVE: To compare the ankle passive stiffness and the plantar flexor muscle performance in patients who underwent unilateral surgical treatment of Achilles tendon rupture with nonsurgical subjects. METHOD: Twenty patients who underwent unilateral surgical treatment of Achilles tendon rupture [surgical (SU) group], and twenty nonsurgical subjects [non-surgical (NS) group] participated in this study. The ankle passive stiffness was evaluated using a clinical test. The concentric and eccentric plantar flexors performance (i.e. peak torque and work) was evaluated using an isokinetic dynamometer at 30°/s. RESULTS: The surgical ankle of the surgical group presented lower stiffness compared to the non-surgical ankle (mean difference=3.790; 95%CI=1.23-6.35) and to the non-dominant ankle of the non-surgical group (mean difference=-3.860; 95%CI=-7.38 to -0.33). The surgical group had greater absolute asymmetry of ankle stiffness (mean difference=-2.630; 95%CI=-4.61 to -0.65) and greater absolute asymmetry of concentric (mean difference=-8.3%; 95%CI=-13.79 to -2.81) and eccentric (mean difference=-6.9%; 95%CI=-12.1 to -1.7) plantar flexor work compared to non-surgical group. There was no other difference in stiffness and plantar flexor performance. CONCLUSION: Patients who underwent surgical repair of the Achilles tendon presented with long-term (1 year or more) deficits of ankle stiffness and asymmetries of ankle stiffness and plantar flexor work in the affected ankle compared to the uninjured side in the surgical group and both sides on the nonsurgical group.

Effectiveness of hip muscle strengthening in patellofemoral pain syndrome patients: a systematic review.

INTRODUCTION: Patellofemoral pain syndrome (PFPS) is characterized by anterior knee pain, which may limit the performance of functional activities. The influence of hip joint motion on the development of this syndrome has already been documented in the literature. In this regard, studies have investigated the effectiveness of hip muscle strengthening in patients with PFPS. OBJECTIVES: The aims of this systematic review were (1) to summarize the literature related to the effects of hip muscle strengthening on pain intensity, muscle strength, and function in individuals with PFPS and (2) to evaluate the methodological quality of the selected studies. METHOD: A search for randomized controlled clinical trials was conducted using the following databases: Google Scholar, MEDLINE, PEDro, LILACS, and SciELO. The selected studies had to distinguish the effects of hip muscle strengthening in a group of patients with PFPS, as compared to non-intervention or other kinds of intervention, and had to investigate the following outcomes: pain, muscle strength, and function. The methodological quality of the selected studies was analyzed by means of the PEDro scale. RESULTS: Seven studies were selected. These studies demonstrated that hip muscle strengthening was effective in reducing pain. However, the studies disagreed regarding the treatments' ability to improve muscle strength. Improvement in functional capabilities after hip muscle strengthening was found in five studies. CONCLUSION: Hip muscle strengthening is effective in reducing the intensity of pain and improving functional capabilities in patients with PFPS, despite the lack of evidence for its ability to increase muscle strength.

Sports injuries profile of a first division Brazilian soccer team: a descriptive cohort study.

OBJECTIVE: To establish the injury profile of soccer players from a first division Brazilian soccer team. In addition, we investigated the association between the characteristics of the injuries and the player's age and position. METHOD: Forty-eight players from a Brazilian first division soccer team were followed during one season. Descriptive statistics were used to characterize the injury profile. Spearman's tests were used to verify the association between the number and severity of injuries and the player's age. Chi-square test was used to verify the association between type of injury and player's position. Fisher's exact test was used to verify the association between the severity of injuries and player's position. RESULTS: The incidence of injuries was 42.84/1000 hours in matches and 2.40/1000 hours in training. The injury severity was 19.5±34.4 days off competition or training. Lower limb was the most common location of injury and most injuries were muscular/tendinous, overuse, non-recurrent, and non-contact injuries. Player's age correlated with the amount and severity of muscle and tendon injuries. Defenders had more minimal injuries (1-3 days lost), while forwards had more moderate (8-28 days lost) and severe injuries (>28 days lost). Furthermore, wingbacks had more muscle and tendon injuries, while midfielders had more joint and ligament injuries. CONCLUSION: The injury profile of the Brazilian players investigated in this study reflected regional differences in soccer practices. Results confirm the influence of the player's age and position on the soccer injuries profile.

Reliability of transverse plane pelvic alignment measurement during the bridge test with unilateral knee extension.

BACKGROUND: The bridge test with unilateral knee extension evaluates the stability of the trunk and pelvis. The evaluation of this stability can contribute to the understanding of the occurrence of musculoskeletal injuries. OBJECTIVES: To investigate the intra- and inter-rater reliability of a qualitative analysis and intra-test reliability of a quantitative analysis of transverse plane pelvic alignment during the bridge test with unilateral knee extension. METHOD: Thirty participants (24.73±4.24 years old) were tested. The qualitative analysis was conducted by asking two raters to judge the transverse plane pelvic alignment and its reliability was assessed with the weighted kappa coefficient (k(w)). The quantitative analysis was conducted by measuring the greatest pelvic tilt angle in transverse plane and its reliability was assessed by use of the intraclass correlation coefficient (ICC); the mean change, which was evaluated using 95% confidence interval of the mean difference (95%CI d) and Bland-Altman plot; and the quantification of measurement variability, which was assessed using standard error of measurement (SEM) and the coefficient of variation of the typical error (CVTE). In addition, the minimal detectable change (MDC95) was determined. RESULTS: The intra-rater reliability ranged from fair to moderate (k(w)=0.32 to 0.58) and the inter-rater reliability was substantial (k(w)=0.80). The intra-test reliability was excellent (ICC=0.82), the 95%CI d ranged from -0.51º to 1.99º, the SEM was 2.38° and the CV(TE) was 28.75%. The MDC95 was 6.59°. CONCLUSIONS: The inter-rater reliability was greater than the intra-rater reliability; the intra-test reliability was excellent and showed no systematic or random error.

Effectiveness of hip muscle strengthening in patellofemoral pain syndrome patients: a systematic review

Introduction: Patellofemoral pain syndrome (PFPS) is characterized by anterior knee pain, which may limit the performance of functional activities. The influence of hip joint motion on the development of this syndrome has already been documented in the literature. In this regard, studies have investigated the effectiveness of hip muscle strengthening in patients with PFPS. Objectives: The aims of this systematic review were (1) to summarize the literature related to the effects of hip muscle strengthening on pain intensity, muscle strength, and function in individuals with PFPS and (2) to evaluate the methodological quality of the selected studies. Method: A search for randomized controlled clinical trials was conducted using the following databases: Google Scholar, MEDLINE, PEDro, LILACS, and SciELO. The selected studies had to distinguish the effects of hip muscle strengthening in a group of patients with PFPS, as compared to non-intervention or other kinds of intervention, and had to investigate the following outcomes: pain, muscle strength, and function. The methodological quality of the selected studies was analyzed by means of the PEDro scale. Results: Seven studies were selected. These studies demonstrated that hip muscle strengthening was effective in reducing pain. However, the studies disagreed regarding the treatments' ability to improve muscle strength. Improvement in functional capabilities after hip muscle strengthening was found in five studies. Conclusion: Hip muscle strengthening is effective in reducing the intensity of pain and improving functional capabilities in patients with PFPS, despite the lack of evidence for its ability to increase muscle strength. .

Sports injuries profile of a first division Brazilian soccer team: a descriptive cohort study

ABSTRACTObjective:To establish the injury profile of soccer players from a first division Brazilian soccer team. In addition, we investigated the association between the characteristics of the injuries and the player's age and position.Method: Forty-eight players from a Brazilian first division soccer team were followed during one season. Descriptive statistics were used to characterize the injury profile. Spearman's tests were used to verify the association between the number and severity of injuries and the player's age. Chi-square test was used to verify the association between type of injury and player's position. Fisher's exact test was used to verify the association between the severity of injuries and player's position.Results: The incidence of injuries was 42.84/1000 hours in matches and 2.40/1000 hours in training. The injury severity was 19.5±34.4 days off competition or training. Lower limb was the most common location of injury and most injuries were muscular/tendinous, overuse, non-recurrent, and non-contact injuries. Player's age correlated with the amount and severity of muscle and tendon injuries. Defenders had more minimal injuries (1-3 days lost), while forwards had more moderate (8-28 days lost) and severe injuries (>28 days lost). Furthermore, wingbacks had more muscle and tendon injuries, while midfielders had more joint and ligament injuries.Conclusion: The injury profile of the Brazilian players investigated in this study reflected regional differences in soccer practices. Results confirm the influence of the player's age and position on the soccer injuries profile.

Confiabilidade da mensuração do alinhamento pélvico no plano transverso durante o teste da ponte com extensão unilateral do joelho / Reliability of transverse plane pelvic alignment measurement during the bridge test with unilateral knee extension

CONTEXTUALIZAÇÃO: O teste da ponte com extensão unilateral do joelho avalia a estabilidade de tronco e pelve. A avaliação dessa estabilidade pode contribuir para o entendimento da ocorrência de lesões musculoesqueléticas. OBJETIVOS: Investigar a confiabilidade intra e interexaminador de uma análise qualitativa e a confiabilidade intrateste de uma análise quantitativa do alinhamento pélvico no plano transverso durante o teste da ponte com extensão unilateral do joelho. MÉTODO: Foram avaliados 30 participantes (24,73±4,24 anos). A análise qualitativa foi realizada pelo julgamento do alinhamento pélvico no plano transverso por dois examinadores, e sua confiabilidade determinada pelo Coeficiente Kappa Ponderado (k w). A análise quantitativa foi realizada pela medida do maior ângulo de desalinhamento pélvico no plano transverso e a confiabilidade determinada pelo Coeficiente de Correlação Intraclasse (CCI); pela análise da mudança na média dos dados, utilizando-se o intervalo de confiança de 95% da média da diferença (95%IC ) e método de Bland-Altman; pelo dimensionamento da variabilidade entre medidas, considerando-se o erro-padrão da medida combinado (EPM) e coeficiente de variação do erro típico (CV ET). Além disso, verificou-se a mudança mínima detectável (MMD95). RESULTADOS: A confiabilidade intraexaminador variou de razoável a moderada (k w=0,32-0,58) e a confiabilidade interexaminador foi substancial (k w=0,80). A confiabilidade intrateste foi excelente (CCI=0,82) e apresentou o IC95% de -0,51º a 1,99º, EPM de 2,38º e o CV ET de 28,75%. O MMD95 foi de 6,59º. CONCLUSÕES: O índice de confiabilidade interexaminador foi superior ao intraexaminador, a confiabilidade intrateste foi excelente e não apresentou erro sistemático e aleatório.

BACKGROUND: The bridge test with unilateral knee extension evaluates the stability of the trunk and pelvis. The evaluation of this stability can contribute to the understanding of the occurrence of musculoskeletal injuries. OBJECTIVES: To investigate the intra- and inter-rater reliability of a qualitative analysis and intra-test reliability of a quantitative analysis of transverse plane pelvic alignment during the bridge test with unilateral knee extension. METHOD: Thirty participants (24.73±4.24 years old) were tested. The qualitative analysis was conducted by asking two raters to judge the transverse plane pelvic alignment and its reliability was assessed with the weighted kappa coefficient (k w). The quantitative analysis was conducted by measuring the greatest pelvic tilt angle in transverse plane and its reliability was assessed by use of the intraclass correlation coefficient (ICC); the mean change, which was evaluated using 95% confidence interval of the mean difference (95%CI ) and Bland-Altman plot; and the quantification of measurement variability, which was assessed using standard error of measurement (SEM) and the coefficient of variation of the typical error (CV TE). In addition, the minimal detectable change (MDC95) was determined. RESULTS: The intra-rater reliability ranged from fair to moderate (k w=0.32 to 0.58) and the inter-rater reliability was substantial (k w=0.80). The intra-test reliability was excellent (ICC=0.82), the 95% CI ranged from -0.51º to 1.99º, the SEM was 2.38º and the CV TE was 28.75%. The MDC95 was 6.59º. CONCLUSIONS: The inter-rater reliability was greater than the intra-rater reliability; the intra-test reliability was excellent and showed no systematic or random error.