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Context: The hip adductor and abductor muscles play vital roles as stabilizers in the lower-extremity. Their activation during soccer-specific actions is essential, but local muscular fatigue can hinder athletic performance and increase the risk of injury. Design: This study aimed to observe the variations in frontal plane hip strength in female college soccer players before and after a high-workload soccer-specific training session. Furthermore, the study sought to compare the relative changes in hip strength with the internal and external load measures obtained during that session. Methods: Twenty female college soccer players participated in a retrospective observational study. Isometric hip adductor and abductor strength were measured before and after a training session in the college spring season. Measurements were taken with a handheld dynamometer (MicroFET 2) while the players were supine. Global positioning system sensors (Catapult Vector S7), commonly worn by players during training sessions and competitive matches, were used to measure external and internal loads. Statistical analyses were performed using paired samples t test to assess hip adductor and abductor strength changes before and after the training session. Spearman rank was used to identify correlation coefficients between global positioning system data and isometric hip strength. Results: The findings revealed significant decreases in the strength of the right hip adduction (P =.012, −7% relative change), right abduction (P =.009, −7.6% relative change), and left abduction (P =.016, −4.9% relative change) after the training session. Furthermore, relative decreases in hip isometric adduction and abduction strength are related to the distance covered at high speeds. Conclusion: The results of this study highlight that hip isometric adduction and abduction strength tend to decrease after exposure to high workloads during soccer-specific training. [ABSTRACT FROM AUTHOR]

Context: Piriformis syndrome is often associated with muscle spasms and shortening of the piriformis muscle (PM). Physical therapy, including static stretching of the PM, is one of the treatments for this syndrome. However, the effective stretching position ofthe PM is unclear in vivo. This study aimed to determine the effective stretching positions of the PM using ultrasonic shear wave elastography. Design: Observational study. Methods: Twenty-one healthy young men (22.7 [2.41 y) participated in this study. The shear elastic modulus of the PM was measured at 12 stretching positions using shear wave elastography. Three of the 12 positions were tested with maximum internal rotation at 0°, 20°, or 40° hip adduction in 90° hip flexion. Nine of the 12 positions were tested with maximum external rotation at positions combined with 3 hip-flexion angles (70°, 90°, and 110°) and 3 hip-adduction angles (0°, 20°, and 40°). Results.' The shear elastic modulus of the PM was significantly higher in the order of 40°, 20°, and 0° of adduction and higher in external rotation than in internal rotation. The shear elastic modulus of the PM was significantly greater in combined 110° hip flexion and 40° adduction with maximum external rotation than in all other positions. Conclusion.- This study revealed that the position in which the PM was most stretched was maximum external rotation with 110° hip ftexion and 40° hip adduction. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the preliminary effects of movement pattern training (MoveTrain) versus strengthening/flexibility (standard) treatment on hip and pelvic biomechanics in patients with chronic hip-related groin pain. This is a secondary analysis of data collected during a pilot randomized clinical trial. Thirty patients with hip pain, between the ages of 15 and 40 years, were randomized to MoveTrain or standard. Both groups completed 10 treatment sessions over 12 weeks along with a daily home exercise program. Three-dimensional motion analysis was used to collect kinematic and kinetic data of the pelvis and hip during a single-leg squat task at pretreatment and immediately posttreatment. Compared with the standard group, the MoveTrain group demonstrated smaller hip adduction angles (P =.006) and smaller hip external adduction moments (P =.008) at posttreatment. The desired changes to hip joint biomechanics, as found in this study, may require specificity in training that could allow health care professionals to better customize the rehabilitation of patients with hip pain. These findings can also be applied to the design and implementation of future clinical trials to strengthen our understanding of the long-term implications of different rehabilitation techniques for patients with hip pain. [ABSTRACT FROM AUTHOR]

Prior studies have explored the relationship between knee valgus and musculoskeletal variables to formulate injury prevention programs, primarily for females. Nonetheless, there is insufficient evidence pertaining to professional male soccer players. Here, the aim was to test the correlation of lateral trunk inclination, hip adduction, hip internal rotation, ankle dorsiflexion range of motion, and hip isometric strength with knee valgus during the single-leg vertical jump test. Twenty-four professional male soccer players performed a single-leg vertical hop test, hip strength assessments, and an ankle dorsiflexion range of motion test. A motion analysis system was employed for kinematic analysis. Maximal isometric hip strength and ankle dorsiflexion range of motion were tested using a handheld dynamometer and a digital inclinometer, respectively. The correlation of peak knee valgus with peak lateral trunk inclination was.43 during the landing phase (P =.04) and with peak hip internal rotation was −.68 (P <.001). For knee valgus angular displacement, only peak lateral trunk inclination presented a moderate positive correlation (r =.40, P =.05). This study showed that trunk and hip kinematics are associated with knee valgus, which could consequently lead to increased knee overload in male professional soccer players following a unilateral vertical landing test. [ABSTRACT FROM AUTHOR]

Hip strength has been shown to influence the incidence of injury in women's football. The first objective of our study was to examine the differences in isometric strength of the adductors and abductors between two test positions (0° vs. 45° hip angle). Our second objective was to verify the sensitivity of the two test positions in discriminating between women footballers with and without a history of groin pain in the last twelve months. One hundred and one elite players from the Slovenian women's football league were tested. The isometric strength of the adductors, abductors, and the ratio between hip abductor and adductor strength in two different test positions were assessed. We found statistically significant differences (p < 0.05; effect size range 0.12–0.13) between the two test positions in hip adduction, abduction strength, and abductor/adductor strength ratio. The ROC analysis showed that only the abductor/adductor strength ratio at the 0° hip angle position can differentiate between players with and without a history of groin pain, with an optimal cut-off point of ≤ 1.01 (p < 0.05; AUC = 0.734). The results should help practitioners plan hip strength training for returning to sport or preventing groin pain among women football players. [ABSTRACT FROM AUTHOR]

Background: The traditional approach for diagnosing piriformis syndrome (PS) is to rule out other causes of sciatica. This approach may lead to unnecessary radiological examinations and a waste of time. In contrast to the traditional approach, we aimed to first exclude PS and determine its prevalence by injecting patients with priformis tenderness. Methods: This observational cross-sectional study included patients diagnosed with PS who had sciatica and tenderness on palpation of the priformis muscle and whose pain was reduced by at least 50% with local injection. Age, sex, pain duration, presence of tenderness in the piriformis muscle, Freiberg test, PACE sign, FADIR, Visual Analog Scale (VAS) score, Douleur Neuropathique 4 Questions (DN4) score, and radiological findings were compared between patients who responded and those who did not respond to the priformis injection. Results: A total of 110 patients with sciatica were evaluated, of whom 66 with tenderness on palpation of the primiformis muscle underwent local injection. In 27 of the 66 patients (40.9%), a decrease in the NRS score of >50% was observed after injection, and PS was diagnosed. There were no statistically significant differences in age, sex, pain duration, Pace, FADIR test positivity, radiological findings, NRS, and DN4 scores, but Freiberg test positivity was statistically higher in patients diagnosed with PS. Conclusion: PS is more common than is thought to be a cause of sciatica. A positive Freiberg test is predictive for the diagnosis of PS, but it should be confirmed by tenderness of the priformis muscle and local injection. Many pathologies can be detected incidentally radiographically in PS; however, they are not predictive of the diagnosis. [ABSTRACT FROM AUTHOR]

The golf swing has been associated with mechanical injury risk factors at many joints. One swing, the Minimalist Golf Swing, was hypothesised to reduce lumbar spine, lead hip, and lead knee ranges of motion and peak net joint moments, while affecting swing performance, compared to golfers' existing swings. Existing and MGS swings of 15 golfers with handicaps ranging from +2 to −20 were compared. During MGS downswing, golfers had 18.3% less lumbar spine transverse plane ROM, 40.7 and 41.8% less lead hip sagittal and frontal plane ROM, and 39.2% less lead knee sagittal plane ROM. MGS reduced lead hip extensor, abductor, and internal rotator moments by 17.8, 19.7 and 43%, while lead knee extensor, abductor, adductor and external rotator moments were reduced by 24.1, 26.6, 37 and 68.8% respectively. With MGS, club approach was 2° shallower, path 4° more in-to-out and speed 2 m/s slower. MGS reduced certain joint ROM and moments that are linked to injury risk factors, while influencing club impact factors with varying effect. Most golf injuries are from overuse, so reduced loads per cycle with MGS may extend the healthy life of joints, and permit golfers to play injury-free for more years. [ABSTRACT FROM AUTHOR]

A novel fixation system for a hand‐held dynamometer (HHD) was designed to enable isometric muscle measurements on various muscle groups of strong, healthy individuals in a field setting. The objective of this study was to evaluate the intra‐ and interrater reliability of the system and determine its suitability for use by multiple researchers within large‐scale data collections during field activities. Four researchers tested eight healthy subjects, who each completed eight different maximal isometric muscle strength assessments using the HHD fixation system. Intraclass correlation coefficients (ICC) results were evaluated with a 95% confidence interval. ICC results for interrater reliability demonstrated excellent agreement of all eight measurements tested. ICC results for intrarater reliability demonstrated excellent agreement for six out of eight measurements. This system provides a new opportunity for several different high‐quality maximal muscle strength measurements to be collected by multiple data collectors on large numbers of strong, healthy individuals in a field setting. Highlights: This system is a reliable testing procedure that provides a new opportunity for several different high‐quality maximal muscle strength measurements.The system allows for laboratory quality data to be collected in the field by multiple data collectors on large numbers of strong, healthy individuals. [ABSTRACT FROM AUTHOR]

Purpose: High body mass index (BMI) is a strong predictor of posttraumatic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR). Altered gait mechanics are independently affected by BMI and ACLR, and influence OA risk. Yet, evidence directly assessing the impact of high BMI on gait or cartilage characteristics after ACLR are limited. Here, we evaluated if high BMI moderates associations between gait and trochlear cartilage structure in individuals with ACLR. Methods: Treadmill walking biomechanics were evaluated in 40 normal BMI and 24 high BMI participants with ACLR at self-selected speeds. Normalized and absolute peak and cumulative loads (i.e., impulse) were extracted for peak knee flexion and adduction moments (KFM, KAM) and vertical ground reaction force (GRF).Medial and lateral femoral cartilage thickness and medial/lateral thickness ratios were assessed via ultrasound. Results: Those with ACLR and high BMI walked with reduced normalized peak vertical GRFs, and greater absolute peak and cumulative loads compared with normal BMI individuals with ACLR. Those with ACLR and high BMI also exhibited thinner cartilage and greater medial/lateral ratios in ACLR limbs compared with contralateral limbs whereas norma lBMI individuals with ACLR exhibited thicker ACLR limb cartilage. Lastly, greater peak KAM and KAM cumulative load were associated with thicker lateral cartilage and lesser medial/lateral thickness ratios, but only in the high BMI group. Conclusions: We observed those with high BMI after ACLR exhibited trochlear cartilage structural alterations not observed in normal BMI patients, whereas differential associations between loading outcomes and cartilage thickness in ACLR knees were observed between groups. Those with high BMI after ACLR may require different therapeutic strategies to optimize joint health in this subset of patients. [ABSTRACT FROM AUTHOR]

The study objective is to test general- and sport-specific adaption during a single training on the Flexibility Trainer. The device is designed to trigger residual muscle tone decreases of the hip-joint muscles by providing (nearly) isokinetic resistance during a full range of motion strength training in adduction/abduction and flexion/extension direction. Static hip flexion and abduction as well as kinematics of double side kicks were analysed on 15 participants before and after training (or rest for controls) to assess general flexibility and sport-specific movement range. Tests were recorded by a Vicon® motion capturing system. Static hip flexion and abduction as well as leg vector spreading angles (VSA) at different nodes of the kick were selected to determine adaptions of active and passive flexibility. Normalised hip joint moments, movement velocities and VSA were calculated to evaluate the training with the device. ANOVAs with 4-repeated measures and Friedman tests were performed to identify time differences and Bonferroni post-hoc test to identify between-subject effects. Significant differences were found for both static flexibility tests (Flexion = 13.65%; Abduction = 9.94%) and the VSA at specific action phases (≤15.15%). Results indicate that short-term adaptions when training with the Flexibility Trainer are exceeding comparable literature showing improved flexibility and sport-specific performance. [ABSTRACT FROM AUTHOR]

BACKGROUND: Lower trapezius (LT) plays an important role in maintaining the stability of the scapula. Sufficient activation of LT can reduce the risk of rotator cuff tear and shoulder impingement syndrome. The Y-raise exercise has been recommended for effective LT activation. However, the upper trapezius (UT) can be co-activated during universal Y-raise exercise. OBJECTIVE: This study aimed to compare the activity of the UT, LT, and serratus anterior (SA) during Y-raise exercise with and without isometric adduction (IAD) using Thera-Band. METHODS: 21 healthy males voluntarily participated in the study. The participants were asked to perform Y-raise exercise with and without IAD using Thera-Band. Surface electromyography was used to measure the muscle activity of UT, LT, and SA during Y-raise exercise with and without IAD. Paired t-test was used to analyze the significance of the muscle activity of UT, LT, and SA as well as the activity ratio of LT/UT and LT/SA. The significance level was set at α = 0.05. RESULTS: Compared with Y-raise exercise without IAD, the muscle activity of UT and SA decreased (p = 0.001 and p = 0.003, respectively), whereas that of LT increased (p = 0.038) during Y-raise exercise with IAD. Additionally, the activity ratio of LT/UT and LT/SA was greater during Y-raise exercise with IAD (p = 0.001 and p = 0.001, respectively). CONCLUSION: Y-raise exercise with IAD using Thera-Band is recommended as an efficient exercise to selectively activate the LT and increase the activity ratio of LT/UT and LT/SA. [ABSTRACT FROM AUTHOR]

Context: Posterior shoulder tightness evaluated as limited glenohumeral internal rotation and horizontal adduction is a risk factor for throwing-related shoulder and elbow injuries. Given that the throwing motion uses the entire body kinematics, limited lower-limb flexibility might be associated with posterior shoulder tightness. Therefore, we aimed to investigate the relationships between posterior shoulder tightness and lower-limb flexibility in college baseball players. Design: Cross-sectional study. Setting: University laboratory. Participants: Twenty-two college baseball players (20 right-handed and 2 left-handed). Methods: To investigate the relationships between glenohumeral range of motion and lower-limb flexibility using simple linear regression analysis, we measured passive range of motion of glenohumeral internal rotation and horizontal adduction, hip internal/external rotation in the prone/sitting position, ankle dorsiflexion, and quadriceps and hamstrings flexibility from both shoulders and legs. Results: Our analysis indicated that decreases in the lead leg hip external rotation in the prone position were moderately associated with limitations in glenohumeral internal rotation (R2 =.250, β [95% confidence interval, CI] = 0.500 [0.149 to 1.392], P =.018) and horizontal adduction (R2 =.200, β [95% CI] = 0.447 [0.051 to 1.499], P =.019) on the throwing shoulder. Furthermore, there were significant moderate relationships between decreases in glenohumeral internal rotation and limited lead leg quadriceps flexibility (R2 =.189, β [95% CI] = 0.435 [0.019 to 1.137], P =.022), and between decreases in glenohumeral horizontal adduction and limited stance leg ankle dorsiflexion (R2 =.243, β [95% CI] = 0.493 [0.139 to 1.438], P =.010). Conclusion: College baseball players with limited lower-limb flexibilities including the lead leg hip external rotation in the prone position, the lead leg quadriceps flexibility, and the stance leg ankle dorsiflexion showed excessive posterior shoulder tightness. The current results support the hypothesis that lower-limb flexibility is associated with posterior shoulder tightness in college baseball players. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study implemented the Copenhagen Adductor Exercise (CAE) and Nordic Hamstring Exercise (NHE) to examine 1) whether CAE and NHE interventions are associated with adductor and hamstring strength gains in youth African male soccer players and 2) whether strength changes after a rest period and secondary intervention. STUDY DESIGN: Pre-post intervention study. METHODS: Forty-four African elite male academy players (age 14.7±1.5 [12-18] years) participated in twice weekly CAE and NHE interventions for 8- and 10-week periods separated by a 4-week rest. Long lever adductor squeeze strength and prone isometric hamstring strength were measured with mixed-effects linear regression models to observe strength changes over time. RESULTS: Ninety-six and 95% of CAE and NHE sessions were completed in each intervention, with no adverse events related to the execution of the exercises. Adductor squeeze strength increased during the first intervention (baseline 3.23 [2.99-3.47] N/kg, post-intervention 3.53 [3.30-3.76] N/kg, p=0.911) and was maintained following the rest period (3.52 [3.27-3.76] N/kg, p=0.999) and second intervention (3.60 [3.35-3.84] N/kg, p=0.002). Hamstring strength improved during the first intervention (baseline 4.95 [4.42-5.49] N/kg, post-intervention 5.48 [4.95-6.02] N/kg, p<0.001), decreased to baseline during the rest period (4.98 [4.44-5.53] N/kg, p=0.996), and did not improve during the second intervention (5.01 [4.46-5.55] N/kg, p=0.978). CONCLUSION: CAE and NHE interventions can be implemented at an elite African academy with high compliance. Adductor and hamstring strength improved in the first intervention, with no further improvements in the second intervention. Secondary interventions therefore should include higher exercise volume or load to improve longitudinal adductor and hamstring strength. Level of Evidence: Level III (Cohort Study) [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament injury prevention should focus primarily on reduction of the knee abduction moment (KAM) in landing tasks. Gluteus medius and hamstring forces are considered to decrease KAM during landing. The effects of different muscle stimulations on KAM reduction were compared using 2 electrode sizes (standard 38 cm2 and half size 19 cm2) during a landing task. Twelve young healthy female adults (22.3 [3.6] y, 1.62 [0.02] m, 50.2 [4.7] kg) were recruited. KAM was calculated under 3 conditions of muscle stimulation (gluteus medius, biceps femoris, and both gluteus medius, and biceps femoris) using 2 electrode sizes, respectively versus no stimulation during a landing task. A repeated-measures analysis of variance determined that KAM differed significantly among stimulation conditions and post hoc analysis revealed that KAM was significantly decreased in conditions of stimulating either the gluteus medius (P <.001) or the biceps femoris (P <.001) with the standard electrode size, and condition of stimulating both gluteus medius and biceps femoris with half-size electrode (P =.012) when compared with the control condition. Therefore, stimulation on the gluteus medius, the biceps femoris, or both muscles could be implemented for the examination of anterior cruciate ligament injury potential. [ABSTRACT FROM AUTHOR]

Background and Aim: To date, little research is available that objectively quantifies female adolescent singing-voice characteristics in light of the physiological and functional developments that occur from puberty to adulthood. This exploratory study sought to augment the pool of data available that offers objective voice analysis of female singers in late adolescence. Methods: Using long-term average spectra (LTAS) and inverse filtering techniques, dynamic range and voice-source characteristics were determined in a cohort of vocally healthy cis-gender female adolescent singers (17 to 19 years) from high-school choirs in Aotearoa New Zealand. Non-parametric statistics were used to determine associations and significant differences. Results: Wide intersubject variation was seen between dynamic range, spectral measures of harmonic organisation (formant cluster prominence, FCP), noise components in the spectrum (high-frequency energy ratio, HFER), and the normalised amplitude quotient (NAQ) suggesting great variability in ability to control phonatory mechanisms such as subglottal pressure (Psub), glottal configuration and adduction, and vocal tract shaping. A strong association between the HFER and NAQ suggest that these non-invasive measures may offer complimentary insights into vocal function, specifically with regard to glottal adduction and turbulent noise in the voice signal. Conclusion: Knowledge of the range of variation within healthy adolescent singers is necessary for the development of effective and inclusive pedagogical practices, and for vocal-health professionals working with singers of this age. LTAS and inverse filtering are useful non-invasive tools for determining such characteristics. [ABSTRACT FROM AUTHOR]

Objective: The Posterior Standing Overhead Arm Reach (SOAR) test has been previously reported as a reliable clinical measure of closed chain hip extension motion. The proposed Medial SOAR test expands on that testing approach to provide a similar measure of functional hip adduction motion. This was a preliminary intrarater and interrater reliability and validity study of the Medial SOAR test as a measure of functional hip adduction. Design: Cross-sectional. Setting: University motion analysis laboratory. Participants: Fifty hips were assessed in 25 (22 female) asymptomatic participants (mean age = 23.4 years, SD = 0.8). Main measures: Maximum hip adduction during the Medial SOAR test was measured with a standard goniometer independently by two examiners. The test was also performed using three-dimensional motion capture. The intrarater and interrater reliability of the goniometric measure was determined using intraclass correlation coefficients, and the relationship between measures obtained via goniometry and three-dimensional motion capture was assessed with Pearson correlations and Bland–Altman analysis. Results: Intrarater reliability (ICC2,3) was 0.88 (95% CI = 0.80–0.92) for Examiner 1 and 0.87 (95% CI = 0.79–0.92) for Examiner 2. The standard error of measurement and minimal detectable change were less than 3.0°. Interrater reliability demonstrated an intraclass correlation coefficient = 0.62 (95% CI = 0.28–0.79). Pearson correlations were significant with low-to-moderate associations (r = 0.49, P < 0.001; r = 0.24, P = 0.045). Conclusions: Similar to the previously reported Posterior SOAR test, the Medial SOAR test demonstrated acceptable intrarater and interrater reliability, along with low-to-moderate associations with three-dimensional motion capture. The Medial SOAR test has the potential to provide a reliable and accurate assessment of closed chain hip adduction. [ABSTRACT FROM AUTHOR]

Background/purpose Interventions including posterior glenohumeral mobilizations (PGM), sleeper stretches, and thoracic manipulation are commonly used to address posterior shoulder tightness. The purpose of this study was to assess the effects of adding thoracic manipulation to PGM and sleeper stretches on passive range of motion (PROM), joint mobility, and infraspinatus electromyographic (EMG) activity in shoulders with decreased internal rotation (IR) PROM. Design Randomized Sequential Intervention Laboratory Study Methods Forty individuals with clinically significant IR loss attended two study sessions. Participants were randomized to receive five 30 seconds bouts of either grade III PGM or sleeper stretching. Following a seven-day washout period, all participants attended a second session and received a prescriptive supine HVLA manipulation targeting the T3-4 segment, followed by the previously randomized intervention. Outcome measures included internal rotation PROM, horizontal adduction PROM, posterior glenohumeral joint translation assessed via ultrasound imaging, and EMG activity of the infraspinatus during a PGM. All outcome measures were assessed pre- and immediately post-intervention and compared statistically. Results There were significant within-group, but not between-group, differences for IR and horizontal adduction PROM following a single session of PGM or sleeper stretch. When combined with thoracic manipulation, significantly smaller within session changes of IR PROM were observed for both PGM (mean difference 4.4, p=0.017) and sleeper stretches (mean difference 6.4, p=0.0005). There were no significant between group differences for horizontal adduction PROM, humeral head translation, or EMG activity across all time points. Discussion Both GH posterior mobilizations and sleeper stretches improved IR and horizontal adduction PROM in a single session. The addition of thoracic manipulation prior to local shoulder interventions resulted in smaller gains of both IR and horizontal adduction ROM. [ABSTRACT FROM AUTHOR]

The aim of our study was to compare the force steadiness and the discharge characteristics of motor units in the tibialis anterior (TA) during ankle dorsiflexion and foot adduction produced by submaximal isometric contractions with the dominant and non-dominant foot. Fifteen young men performed maximal and submaximal contractions at five target forces with both legs, and motor unit activity in TA was recorded using high-density electromyography. Maximal force and the fluctuations in force during submaximal contractions were similar between the two legs (p > 0.05). Motor unit activity was characterized by measures of mean discharge rate (MDR), coefficient of variation for interspike interval (CoV for ISI), and standard deviation of the filtered cumulative spike train (SD of fCST). There were no statistically significant differences in motor unit activity between legs during ankle dorsiflexion. In contrast, the MDR and the CoV for ISI but not the SD of fCST, were greater for the non-dominant foot compared with the dominant foot during foot adduction. Nonetheless, these differences in motor unit activity were not sufficient to influence the force fluctuations during the submaximal contractions. These results indicate that control of the force produced by TA during the two actions was not influenced by limb dominance. [ABSTRACT FROM AUTHOR]

Context: Elite golfers have a high incidence of low back pain. Recent reviews have emphasized the need for investigation into how to prevent low back pain in golfers, prompting the current study. Design: Prospective longitudinal cohort study. Methods: Forty-one injury-free golfers were included in this study. At baseline, lower quadrant joint angles and club and ball performance were measured while each golfer performed 10 drives. The golfers were then monitored for 6 months and were allocated into 2 groups depending on whether or not they developed low back pain. The initial, baseline kinematic variables of the low back pain group and the uninjured group were then compared. Results: Over the 6-month monitoring period, 17 (41%) of the golfers developed low back pain. At baseline assessment, the low back pain group had 4° less lead ankle dorsiflexion at setup (P = .01; effect size = 0.82), 6° less lead knee flexion at the top of the backswing (P = .05; effect size = 0.64), 6° less lead ankle dorsiflexion at the top of the backswing (P = .01; effect size = 0.82), 6° more trail hip adduction at the top of the backswing (P = .02; effect size = 0.79), 9° more trail knee flexion at impact (P = .05; effect size = -0.64), and 6° more trail hip adduction at the end of follow through (P < .00; effect size = 1.00). Conclusion: Golfers who developed low back pain during the 6-month monitoring period displayed distinct differences in biomechanics at baseline when all golfers were injury free. These biomechanical differences may be considered a precursor to injury. Three-dimensional motion analysis may indicate whether elite golfers are at risk of developing low back pain. Research is needed to assess whether targeted exercise and sports drills aimed at addressing the biomechanical risk factors identified may prevent low back pain in elite golfers. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to compare functional movement screen (FMS) scores and drop vertical jump (DVJ) kinematics between those with and without anterior cruciate ligament reconstruction (ACLR), and to evaluate the association between FMS composite score and DVJ kinematics. Design: Cross-sectional. Participants: Sixty individuals with and without a history of ACLR. Main Outcome Measures: Composite FMS score and the dorsiflexion, knee-flexion, hip-flexion, knee abduction, hip adduction, and trunk-flexion angles during a DVJ. Results: The FMS scores did not differ between groups (P > .05). There were smaller peak and initial contact hip-flexion angles in the ACLR and contralateral limbs compared with controls, and smaller peak dorsiflexion angles in the ACLR compared with contralateral limbs (P < .05). Lower FMS score was associated with a smaller peak dorsiflexion angle, smaller peak knee-flexion angle, and larger peak knee abduction angle in the ACLR limb (ΔR² = .14-.23); a smaller peak dorsiflexion angle and smaller peak knee-flexion angle in the contralateral limb (ΔR² = .17-.19); and a smaller peak dorsiflexion angle, smaller peak knee-flexion angle, and larger peak knee abduction angle in the control limb (ΔR² = .16-.22). Conclusion: The FMS scores did not differ between groups, but were associated with DVJ kinematics and should be a complementary rather than substitute assessment. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the differences in hip adductor and abductor muscle strength in elite male footballers from youth to senior level. Methods: We tested 125 players from the under-13-years (U'13) to senior squads of a Danish male professional football club in this cross-sectional design study. Hip adductor and abductor force (in newtons), torque (in newton meters), normalized torque (in newton meters per body mass), and adduction-to-abduction ratio were measured using handheld dynamometry. Results: Between U'13 and senior level, adductor force increased by 104%, torque by 127%, and normalized torque by 21%. Abductor force increased by 78%, torque by 126%, and normalized torque by 17%. For incremental differences between age groups, significant increases were observed between the ages of U'13 to U'14 (18%–39%) and U'14 to U'15 (19%–33%) for all strength measures (P ≤.021). No incremental difference was observed for adductor-to-abductor ratio. Conclusions: The large increases in hip adductor and abductor strength occurring between the ages of U'13 and U'15 offer insight into the strength capabilities and stress demands in these players, which may relate to injury vulnerability, and facilitate clinicians in selecting best-suited exercise interventions. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to compare maximal force, force steadiness, and the discharge characteristics of motor units in the tibialis anterior (TA) muscle during submaximal isometric contractions for ankle dorsiflexion and adduction of the foot. Methods: Nineteen active young adults performed maximal and submaximal isometric dorsiflexion and adduction contractions at five target forces (5%, 10%, 20%, 40%, and 60% maximal voluntary contraction [MVC]). The activity of motor units in TA was recorded by high-density EMG. Results: The maximal force was similar between dorsiflexion and adduction, despite EMG amplitude for TA being greater (P < 0.05) during dorsiflexion than adduction. The coefficient of variation (CV) for force (force steadiness) during dorsiflexion was always less (P < 0.05) than during adduction, except of 5% MVC force. No differences were observed for mean discharge rate; however, the regression between the changes in discharge rate relative to the change of force was significant for dorsiflexion (R² = 0.25, P < 0.05) but not for adduction. Discharge variability, however, was usually less during dorsiflexion. The CV for interspike interval was less (P < 0.05) at 10%, 20%, and 40% MVC but greater at 60% MVC during dorsiflexion than adduction. Similarly, the SD values of the filtered cumulative spike train of the motor units in TA were less (P < 0.05) at 5%, 10%, 20%, and 40% MVC during dorsiflexion than adduction. Conclusions: Although the mean discharge rate of motor units in TA was similar during foot adduction and ankle dorsiflexion, discharge variability was less during dorsiflexion resulting in less accurate performance of the steady adduction contractions. The neural drive to bifunctional muscles differs during their accessory function, which must be considered for training and rehabilitation interventions. [ABSTRACT FROM AUTHOR]

Background: Historically, kinematic measures have been compared across injured and non-injured groups of runners, failing to take into account variability in kinematic patterns that exist independent of injury, and resulting in false positives. Research led by gait patterns and not pre-defined injury status is called for, to better understand running-related injury (RRI) aetiology and within- and between-group variability. Objectives: Synthesise evidence for the existence of distinct kinematic sub-groups across a population of injured and healthy runners and assess between-group variability in kinematics, demographics and injury incidence. Data Sources: Electronic database search: PubMed, Web of Science, Cochrane Central Register of Controlled Trials (Wiley), Embase, OVID, Scopus. Eligibility Criteria: Original, peer-reviewed, research articles, published from database start to August 2022 and limited to English language were searched for quantitative and mixed-methods full-text studies that clustered injured runners according to kinematic variables. Results: Five studies (n = 690) were included in the review. All studies detected the presence of distinct kinematic sub-groups of runners through cluster analysis. Sub-groups were defined by multiple differences in hip, knee and foot kinematics. Sex, step rate and running speed also varied significantly between groups. Random injury dispersal across sub-groups suggests no strong evidence for an association between kinematic sub-groups and injury type or location. Conclusion: Sub-groups containing homogeneous gait patterns exist across healthy and injured populations of runners. It is likely that a single injury may be represented by multiple movement patterns, and therefore kinematics may not predict injury risk. Research to better understand the underlying causes of kinematic variability, and their associations with RRI, is warranted. [ABSTRACT FROM AUTHOR]

Objective The aims of this study were to assess the psychological, functional, and physical differences between patients with femoroacetabular impingement (FAI) syndrome and individuals who were asymptomatic (controls) to analyze clinical differences among 4 subtypes of FAI (cam type, cam type with labral tear, pincer type, and pincer type with labral tear), to calculate the correlations among the variables described, and to identify risk factors contributing to the hip function variance. Methods A case–control study was conducted at a hospital rehabilitation unit with a cohort of individuals who were asymptomatic (controls) and a cohort of patients with FAI. Sociodemographic characteristics, pain intensity, psychological health status, hip range of motion (RoM), hip isometric strength, and hip function were assessed. Results A total of 69 controls and 69 patients with FAI were analyzed. Although sociodemographic characteristics were comparable between samples, poorer hip RoM, strength, and psychological health were found for the cases. FAI subtypes showed no significant pain intensity, psychological health, or RoM differences (except for hip adduction), but hip strength differed among FAI subtypes. Multiple significant correlations between psychological health, pain intensity, RoM, strength, and hip function were found. The variance values of the International Hip Outcome Tool, Hip Outcome Score (HOS) for daily living activities, and HOS for sports activities were partially explained (47.6%, 36.0%, and 21.6%, respectively) on the basis of kinesiophobia, hip strength, self-efficacy, and anxiety. Conclusion Patients with FAI showed poorer psychological health, hip RoM, and strength than individuals who were asymptomatic and had similar sociodemographic characteristics. FAI subtype influenced the patients' clinical presentations. Hip strength, kinesiophobia, anxiety, and self-efficacy should be targeted for improving hip function, as they have been demonstrated to be important contributors to hip disability. Impact This study demonstrated that pain catastrophizing, hip strength, and hip adduction differed among FAI subtypes. However, hip function and pain intensity were comparable between FAI subtypes. [ABSTRACT FROM AUTHOR]

Background: Slipped capital femoral epiphysis (SCFE) is the most common hip disease during infancy and adolescence. Our study aimed to analyze static plantar pressure in children with surgically treated unilateral SCFE. Methods: Twenty-two children with right SCFE with in situ fixation with one percutaneous screw were assessed by PoData plantar pressure analysis under three different conditions (open eyes, eyes closed, and head retroflexed). Results: The total foot loading was significantly higher on the unaffected limb compared with the affected one for all the three testing conditions (p < 0.05). When assessing the differences between testing conditions, there were no significant differences for the right and left foot loadings, or for the three sites of weight distribution, except for the right fifth metatarsal head (lower loading in eyes-closed condition in comparison to eyes open, p = 0.0068), left fifth metatarsal head (increased loading in head-retroflexed condition in comparison to eyes open, p = 0.0209), and left heel (lower loading in head-retroflexed condition in comparison to eyes open, p = 0.0293). Conclusion: Even after a successful surgical procedure, differences in foot loading can impact the postural static activities in different conditions (natural eyes-open, eyes-closed, or head-retroflexed posture). [ABSTRACT FROM AUTHOR]

Purpose: This study investigates the relationship between the scores of upper extremity functional tests with isokinetic strength, range of motion, shoulder proprioception, and posture of male volleyball players. Methods: A total of 30 male university volleyball players aged 18 to 24 years were selected by the convenience sampling method. The concentric... [ABSTRACT FROM AUTHOR]

Introduction: For individuals with limb loss, bone-anchored implants create a direct structural and functional connection to a terminal prosthesis. Here, we characterized the mechanical loads distal to the abutment during several functional performance tests in Service members with transfemoral (TF) limb loss, to expand on prior work evaluating more steady-state ambulation on level ground or slopes/stairs. Methods: Two males with unilateral TF limb loss and two males with bilateral TF limb loss participated after two-stage osseointegration (24 and 12 months, respectively). Tri-directional forces and moments were wirelessly recorded through a sensor, fit distal to the abutment, during six functional tests: Timed Up and Go (TUG), Four Square Step Test (FSST), Six Minute Walk Test (6MWT), Edgren Side-Step Test (SST), T-Test (TTEST), and Illinois Agility Test (IAT). Additionally, participants performed a straight-line gait evaluation on a 15 m level walkway at a self-selected speed (0.93-1.24 m/s). Peak values for each component of force and moment were extracted from all six functional tests; percent differences compared each peak with respect to the corresponding mean peak in straight-line walking. Results: Peak mechanical loads were largest during non-steady state components of the functional tests (e.g., side-stepping during SST or TTEST, standing up from the ground during IAT). Relative to walking, peak forces during functional tests were larger by up to 143% (anterior-posterior), 181% (medial-lateral), and 110% (axial); peak moments were larger by up to 108% (flexion-extension), 50% (ab/adduction), and 211% (internal/external rotation). Conclusions: A more comprehensive understanding of the mechanical loads applied to bone-anchored implants during a variety of activities is critical to maximize implant survivability and long-term outcomes, particularly for Service members who are generally young at time of injury and return to active lifestyles. [ABSTRACT FROM AUTHOR]

Background: Arytenoid asymmetry is usually an incidental finding during video-pharyngo-laryngoscopic examinations, and few otolaryngologists have described the clinical implications of this among patient with laryngeal disorders. Aim: The aim of the study is to document the prevalence of arytenoid adduction asymmetry in patients who had video-pharyngo-laryngoscopy and determine if there is any possible association between arytenoid adduction asymmetry and hoarseness. Methods: This is a retrospective descriptive study involving patients who had video-pharyngo-laryngoscopic examinations for various indications. The medical charts and video-pharyngo-laryngoscopic examination findings recorded in the stored database in ENT outpatient departments of two institutions over a 2-year period were retrospectively reviewed for age, sex, occupation, presenting complaint, and indication for video-pharyngo-laryngoscopic findings and diagnosis. Arytenoid adduction asymmetry was defined in relation to the position of the corniculate cartilages, cuneiform cartilages, and aryepiglottic angle. All the variables in the data were analyzed using Statistical Product and Service Solution (SPSS) version 25. Results: A total of 152 out of 209 patients had complete information needed for the review, 59 were males and 93 females with age range 20–91 years, and mean age was 46 ± 15.5 years. The overall prevalence rate for adduction asymmetry was 44.7%. Arytenoid asymmetry was seen commonest among the 5th and 6th decades of life and highest among the professional voice users (55%), while the male-to-female ratio was 1.6:1. Hoarseness constituted 40.1% of all indications for video-pharyngo-laryngoscopy, with 71% of patients with hoarseness having a primary laryngeal lesion, 26% had laryngopharyngeal reflux, and 3.3% were due to pubertal voice changes. A significant association was found between arytenoid asymmetry of the male gender P-value 0.027 and hoarseness P-value 0.026. Conclusion: Arytenoid adduction asymmetry is prevalent in the 5th and 6th decades of life, among patients with hoarseness resulting from unilateral primary laryngeal disorders. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to compare three-dimensional kinematic of the trunk, pelvis, hip, and knee during the single-leg squat and hip torque in individuals with and without isolated patellofemoral osteoarthritis (PFOA). Patients and methods: This cross-sectional study evaluated trunk, pelvis, hip, and knee kinematics at 30°, 45°, and 60° knee flexion during the single-leg squat using the Vicon motion capture and analysis system, the Nexus System 2.1.1, and 3D Motion Monitor software. Sixteen individuals (8 males, 8 females; mean age: 49.3±6.2 years; range 40 to 61 years) participated in the study, of which eight were PFOA patients and eight were healthy controls. Isometric hip abductor, extensor, and external rotator torques were evaluated using a handheld dynamometer. Results: The PFOA group exhibited greater hip adduction at 30° (p=0.008), 45° (p=0.005), and 60° (p=0.008) knee flexion in the descending phase of the single-leg squat, as well as at 60° (p=0.009) and 45° (p=0.03) knee flexion in the ascending phase. No significant differences were found between groups for other kinematic variables (p>0.05). The PFOA group exhibited lower isometric hip abductor (p=0.02), extensor (p<0.001), and external rotator (p=0.007) torques. Conclusion: Individuals with PFOA exhibited excessive hip adduction that could increase stress on the lateral patellofemoral joint at 30°, 45°, and 60° knee flexion during the single-leg squat and exhibited weakness of the hip abductors, extensors, and external rotators in comparison to healthy controls. [ABSTRACT FROM AUTHOR]

Objectives: Subacromial impingement syndrome is one of the most prevalent causes of shoulder pain in dialysis patients. The aim of this study is to evaluate the effectiveness of Kinesio tape in combination with mobilization versus mobilization alone on rest pain, shoulder abduction pain, shoulder abduction range of motion (ROM), and... [ABSTRACT FROM AUTHOR]

Background: Changes in knee loading have been reported after meniscectomy. Knee loading has previously been assessed during jogging and treadmill running rather than overground running, which could give altered results. Purpose/Hypothesis: The purpose of this study was to evaluate knee function during overground running and walking after meniscectomy. It was hypothesized that the affected limb would demonstrate higher external knee adduction moment, lower knee flexion moment (KFM), and lower knee rotation moment (KRM) compared with the contralateral limb and with healthy individuals. Study Design: Controlled laboratory study. Methods: Kinematic and kinetic data were collected during running and walking in individuals after a meniscectomy and healthy individuals. Total knee joint moments (TKJM) were calculated from the sagittal, frontal, and transverse knee moments. Isometric quadriceps strength, perceived knee function, and kinesiophobia were also assessed. A mixed linear model compared differences between the affected leg, the contralateral leg, and the healthy leg. Results: Data were collected on 20 healthy individuals and 30 individuals after a meniscectomy (mean ± SD, 5.7 ± 2.9 months postsurgery), with 12, 16, and 2 individuals who had medial, lateral, and both medial and lateral meniscectomy, respectively. The affected limb demonstrated lower TKJM (P <.001), KFM (P =.004), and KRM (P <.001) during late stance of walking compared with the healthy group. Lower TKJM and KFM were observed during running in the affected limb compared with the contralateral limb and healthy group. No significant differences were observed between contralateral and healthy limbs except for KRM during late stance of walking. Lower quadriceps strength was observed in the affected (P <.001) and contralateral limbs (P =.001) compared with the healthy group. Individuals after a meniscectomy also reported greater kinesiophobia (P =.006) and lower perceived knee function (31.1%; P <.001) compared with the healthy group. Conclusion: After meniscectomy, individuals who sustained a traumatic meniscal injury showed lower TKJM in the affected limb compared with the contralateral limb and healthy individuals. This decrease in TKJM can be attributed to altered knee-loading strategies in the sagittal and transverse planes. Clinical Relevance: Improving movement strategies, quadriceps strength, and kinesiophobia through rehabilitation approaches will allow individuals to load their knee appropriately when returning to sport. Registration: NCT03379415 (ClinicalTrials.gov identifier). [ABSTRACT FROM AUTHOR]

Context: It is unclear if lower-extremity joint cooling alters biomechanics during a functional movement. Objective: To investigate the effects of unilateral lower-extremity cryotherapy on movement alterations during a single-leg drop jump. Design: A crossover design. Setting: Laboratory. Patients: Twenty healthy subjects (10 males and 10 females; 23 y, 169 cm, 66 kg). Intervention(s): Subjects completed a single-leg drop jump before and after a 20-minute ankle or knee joint cooling on the right leg, or control (seated without cooling) on 3 separate days. Main outcome measures: Time to peak knee flexion, vertical ground reaction force, lower-extremity joint angular velocity (sagittal plane only), and angle and moment (sagittal and frontal planes) in the involved leg over the entire ground contact (GC; from initial contact to jump-off) during the first landing. Time to peak knee flexion was compared using an analysis of variance; the rest of the outcome measures were analyzed using functional analyses of variance (P < .05). Results: Neither joint cooling condition changed the time to peak knee flexion (F2,95 = 0.73, P = .49). Ankle joint cooling reduced vertical ground reaction force (55 N at 4% of GC), knee joint angular velocity (44°/s during 5%-9% of GC), and knee varus moment (181 N·m during 18%-20% of GC). Knee joint cooling resulted in a reduction in knee joint angular velocity (24°/s during 37%-40% of GC) and hip adduction moment (151 N·m during 46%-48% of GC), and an increase in hip joint angular velocity (16°/s during 49%-53% of GC) and plantarflexion angle (1.5° during 11%-29% of GC). Conclusion: Resuming activity immediately after lower-extremity joint cooling does not seem to predispose an individual to injury during landing because altered mechanics are neither overlapping with the injury time period nor of sufficient magnitude to lead to an injury. [ABSTRACT FROM AUTHOR]

Background: Flat foot is a condition in which the Medial longitudinal arch (MLA) has a more flattened curve when foot makes full contact with the ground. In medical terms, flat foot is associated with the pronated foot. For people ages 20 to 60, flat foot prevalence is 13.6%. People who have weak posterior tibial tendons are more likely to have flat feet and Flat foot is one of the contributing factors to development of anterior knee pain. Purpose: To compare the effectiveness of Tibialis posterior strengthening exercise and Quadriceps strengthening exercise among people with anterior knee pain. Materials and Method: The experimental study included 170 volunteers, both male and female, aged 20-60 years, who were drawn from Martin Physiotherapy Clinic by convenience sample method. informed consent was obtained before beginning the study. The participants were divided into two groups, the Tibialis posterior (n=85) group received Tibialis posterior strengthening exercise, whereas the Quadriceps (n=85) group received Quadriceps strengthening exercise. The intervention was administered five times over the course of six weeks. Study Period: March 2023 to July 2023. Results: The collected data was statistically analysed using paired and unpaired t-test, showed significant improvement in Tibialis posterior group than quadriceps group with p<0.0001. Conclusion: The study concludes that Tibialis posterior strengthening was more effective in reducing pain and improving functional status among peoples with anterior knee pain. [ABSTRACT FROM AUTHOR]

Background and purpose. Many regularly performed spikes and serves lead to a shoulder girdle adaptation that could be sport-specific and result in traumatic events. The aim was to evaluate shoulder joints' range of movements (ROM), peak isometric strength of arm muscles, submaximal force repetition error, and upper body dynamic stability in adolescent female volleyball players. Materials and methods. 15 qualified, 17.7 ± 2.1-year-old, female volleyball players participated. The shoulder active ROM of internal rotation (IR), external rotation (ER), flexion, extension, abduction, adduction, horizontal abduction (HABD), and horizontal adduction (HADD) were measured. The peak force and the ability to repeat the same submaximal force of IR, ER, and extension were determined. Dynamic stability was detected by the Y-upper-body dynamic balance test (Y-UBDST). Results. The ER ROM was increased but the IR and HADD ROMs were decreased on both shoulders. The extension and adduction ROMs were smaller in the dominant (D) shoulder (p < 0.05). The D arm's IR, ER, and extension muscles developed greater peak forces (p < 0.05). ER/IR muscles' peak forces ratio was 0.94 ± 0.18 in both shoulders. The ER and extension muscles submaximal force repetition error was smaller in the D arm (p < 0.05). The mean score of the normalized reaching distances in the Y-UBDST was symmetrical: 95 ± 6% in the D and 94 ± 7% in the non-dominant (ND) arm. The correlation between the rotators' peak force and the Y-UBDBT was not significant. Conclusions. The shoulder girdle characteristics were optimal and adaptable for volleyball spike and serve movements in those adolescent qualified female volleyball players without pathological changes in pre-season. [ABSTRACT FROM AUTHOR]

BACKGROUND: Strength differences between performance levels remain unclear in female football. Furthermore, the relationship between fulltime training and strength has been unexplored despite increased professionalisation in the sport. OBJECTIVE: The aims of this research were to examine knee flexor/extensor and hip adductor/abductor strength differences between elite and sub-elite female footballers, and then determine the relationship of strength performance to age, years of football experience (FE), and years of fulltime training (FTT). METHODS: 15 elite and 15 sub-elite professional female footballers were tested. The main outcomes were concentric isokinetic knee flexor and extensor peak moment at 60, 180, and 300 ∘ /s, and isometric hip adductor (ADD) and abductor (ABD) force. RESULTS: The elite team had higher absolute (300 ∘ /s: 47.13–49.33 Nm vs 37.33–38.93 Nm, p < 0.05) and normalised (300 ∘ /s: 0.76–0.80 Nm/kg vs 0.59–0.62 Nm/kg, p < 0.05) knee flexor values, and higher normalised ADD (5.64–5.66 N/kg vs 4.98–5.05 N/kg, p < 0.05) and ABD force (5.80–6.00 N/kg vs 5.26–5.39 N/kg, p < 0.05), compared to the sub-elite team. Age, FE, and FTT were correlated to knee flexor values (r = 0.381–0.559, p < 0.05). Additionally, FTT was correlated with normalised ADD and ABD force (r = 0.362–0.546, p < 0.05). CONCLUSION: Sub-elite female footballers may require additional knee flexor and hip strengthening in order to make the step up to the elite level. Those who are younger or have low FTT may also be recommended additional lower limb strengthening ahead of joining a fulltime training environment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Measurements of hip abduction (ABD) and adduction (ADD) are important in strength and conditioning as well as in clinical practice. However, there is no clear consensus on how ABD and ADD compare in strength in different populations. OBJECTIVE: The aim was to perform a quantitative synthesis of comparisons between the isometric strength of ABD and ADD in different populations. METHODS: ABD and ADD strength data were collected and pooled mean values for ABD:ADD strength ratio were calculated and expressed as standardized mean differences. Forty studies of healthy adults, 5 studies of healthy older adults and 14 studies of adults with various musculoskeletal injuries were included in the analysis. RESULTS: Healthy (non-athletic) males, healthy older adults, and adults with hip and groin pathologies or osteoarthritis tend to have the same ADD and ABD strength; male athletes tend to have a stronger ADD compared with ABD; healthy females and adults with patellofemoral pain tend to have a stronger ABD compared with ADD. CONCLUSIONS: These results can serve as a database to help compare and interpret measurements of ADD and ABD strength ratio in different populations. [ABSTRACT FROM AUTHOR]

Knee abduction/adduction moment and knee internal rotation moment are known surrogate measures of anterior cruciate ligament (ACL) load during tasks like sidestepping and single-leg landing. Previous experimental literature has shown that a variety of kinematic strategies are associated or correlated with ACL injury risk; however, the optimal kinematic strategies needed to reduce peak knee moments and ACL injury are not well understood. To understand the complex, multifaceted kinematic factors underpinning ACL injury risk and to optimize kinematics to prevent the ACL injury, a musculoskeletal modeling and simulation experimental design was used. A 14-segment, 37-degree-of-freedom, dynamically consistent skeletal model driven by force/torque actuators was used to simulate whole-body single-leg jump landing kinematics. Using the residual reduction algorithm in OpenSim, whole-body kinematics were optimized to reduce the peak knee abduction/adduction and internal/external rotation moments simultaneously. This optimization was repeated across 30 single-leg jump landing trials from 10 participants. The general optimal kinematic strategy was to bring the knee to a more neutral alignment in the transverse plane and frontal plane (featured by reduced hip adduction angle and increased knee adduction angle). This optimized whole-body kinematic strategy significantly reduced the peak knee abduction/adduction and internal rotation moments, transferring most of the knee load to the hip. [ABSTRACT FROM AUTHOR]

In this study, the effects of an exercise therapy comprising yoga exercises and medial-thrust gait (YogaMT) on lower-extremity kinetics, pain, and function in patients with medial knee osteoarthritis were investigated. Fifty-nine patients were randomly allocated to three treatment groups: (a) the YogaMT group practiced yoga exercises and medial thrust gait, (b) the knee-strengthening group performed quadriceps- and hamstring-strengthening exercises, and (c) the treadmill walking group practiced normal treadmill walking in 12 supervised sessions. The adduction and flexion moments of the hip, knee, and ankle; pain intensity; and 2-min walking test were assessed before and after treatment and at 1-month follow-up. The YogaMT group experienced a significant reduction in knee adduction moment. All groups showed significant improvement in pain and function. The YogaMT may reduce medial knee load in patients with knee osteoarthritis in the short term. A larger clinical trial is required to investigate the long-term outcomes of this intervention. [ABSTRACT FROM AUTHOR]

Context: Three per thousand births have Erb's palsy. Spontaneous recovery is 50%. Co-activation yields poor outcomes. There are no objective indicators of its emergence. Aims: Analyze if 1 month Axon Viability Index (AVI) of the axillary nerve and which active movement score (AMS) measures can predict co-activation. Settings and Design: Tertiary level rehabilitation center, retrospective design. Methods and Material: The electronic medical record (EMR) was reviewed for patients with Erb's palsy with Narakas grade 2 lesions, as having co-activation or not. The one-month Axillary AVI was used with monthly AMS scores. The inclusion criteria were an AVI greater than ten percent. Exclusion criteria were bi-brachial palsy, congenital anomalies, concomitant or subsequent neurological injuries, and orthopedic injuries. Statistical Analysis Used: Descriptive statistics were used to calculate the median and interquartile values for AMS scores at each respective time point. Statistical significance for each time point was determined using a student's t-test. Results: Regarding the t-test on the AVI data, a significant P value of 0.001 was found favoring the co-activation group. AVI of the Axillary nerve between 0.1 and 0.5 at 1 month is a reliable indicator of future development of co-activation. The following were strong indicators of the emergence of co-activation respectively: month three Wrist Extension in sitting, Shoulder Abduction in supine, Shoulder Abduction in sitting, Elbow Flexion in sitting, month six Elbow Flexion in sitting, month seven Elbow Flexion in sitting. Conclusions: The axillary AVI at one month is a good predictor of future development of co-activation. The mentioned AMS items are the earliest indicators of co-activation. [ABSTRACT FROM AUTHOR]

Context: Examining the coordinated coupling of muscle recruitment patterns may provide insight into movement variability in sport-related tasks. Objective: The purpose of this study was to examine the relationship between coupled gluteus maximus and medius recruitment patterns and hip-adduction variability during single-limb step-downs. Design: Cross-sectional. Setting: Biomechanics laboratory. Participants: Forty healthy adults, including 26 women and 14 men, mean age 23.8 (1.6) years, mean body mass index 24.2 (3.1) kg/m2, participated. Interventions: Lower-extremity kinematics were acquired during 20 single-limb step-downs from a 19-cm step height. Electromyography (EMG) signals were captured with surface electrodes. Isometric hip-extension strength was obtained. Main Outcome Measures: Hip-adduction variability, measured as the SD of peak hip adduction across 20 repetitions of the step-down task, was measured. The mean amplitudes of gluteus maximus and gluteus medius EMG recruitment were examined. Determinism and entropy of the coupled EMG signals were computed with cross-recurrence quantification analyses. Results: Hip-adduction variability correlated inversely with determinism (r = −.453, P =.018) and positively with entropy (r =.409, P =.034) in coupled gluteus maximus/medius recruitment patterns but not with hip-extensor strength nor with magnitudes of mean gluteus maximus or medius recruitment (r = −.003,.081, and.035; P =.990,.688, and.864, respectively). Conclusion: Hip-adduction variability during single-limb step-downs correlated more strongly with measures of coupled gluteus maximus and medius recruitment patterns than with hip-extensor strength or magnitudes of muscle recruitment. Examining coupled recruitment patterns may provide an alternative understanding of the extent to which hip neuromuscular control modulates lower-extremity kinematics beyond examining muscle strength or EMG recruitment magnitudes. [ABSTRACT FROM AUTHOR]

Context: Patellofemoral pain (PFP) is a challenging condition, with altered kinematics and muscle activity as 2 common impairments. Single applications of patterned electrical neuromuscular stimulation (PENS) have improved both kinematics and muscle activity in females with PFP; however, the use of PENS in conjunction with a rehabilitation program has not been evaluated. Objective: To determine the effects of a 4-week rehabilitation program with PENS on lower-extremity biomechanics and electromyography (EMG) during a single-leg squat (SLS) and a step-down task (SDT) in individuals with PFP. Study Design: Double-blinded randomized controlled trial. Setting: Laboratory. Patients of Other Participants: Sixteen females with PFP (age 23.3 [4.9] y, mass 66.3 [13.5] kg, height 166.1 [5.9] cm). Intervention: Patients completed a 4-week supervised rehabilitation program with or without PENS. Main Outcome Measures: Curve analyses for lower-extremity kinematics and EMG activity (gluteus maximus, gluteus medius, vastus medialis oblique, vastus lateralis, biceps femoris, and adductor longus) were constructed by plotting group means and 90% confidence intervals throughout 100% of each task, before and after the rehabilitation program. Mean differences (MDs) and SDs were calculated where statistical differences were identified. Results: No differences at baseline in lower-extremity kinematics or EMG were found between groups. Following rehabilitation, the PENS group had significant reduction in hip adduction between 29% and 47% of the SLS (MD = 4.62° [3.85°]) and between 43% and 69% of the SDT (MD = 6.55° [0.77°]). Throughout the entire SDT, there was a decrease in trunk flexion in the PENS group (MD = 10.91° [1.73°]). A significant decrease in gluteus medius activity was seen during both the SLS (MD = 2.77 [3.58]) and SDT (MD = 4.36 [5.38]), and gluteus maximus during the SLS (MD = 1.49 [1.46]). No differences were seen in the Sham group lower-extremity kinematics for either task. Conclusion: Rehabilitation with PENS improved kinematics in both tasks and decreased EMG activity. This suggests that rehabilitation with PENS may improve muscle function during functional tasks. [ABSTRACT FROM AUTHOR]

The superficial hip adductor muscles are situated in close proximity to each other. Therefore, relative movement between the overlying skin and the muscle belly could lead to a shift in the position of surface electromyography (EMG) electrodes and contamination of EMG signals with activity from neighboring muscles. The aim of this study was to explore whether hip movements or isometric contraction could lead to relative movement between the overlying skin and 3 adductor muscles: adductor magnus, adductor longus, and adductor gracilis. The authors also sought to investigate isometric torque--EMG relationships for the 3 adductor muscles. Ultrasound measurement showed that EMG electrodes maintained a position which was at least 5 mm within the muscle boundary across a range of hip flexion--extension angles and across different contraction levels. The authors also observed a linear relationship between torque and EMG amplitude. This is the first study to use ultrasound to track the relative motion between skin and muscle and provides new insight into electrode positioning. The findings provide confidence that ultrasound-based positioning of EMG electrodes can be used to derivemeaningful information on output from the adductor muscles and constitute a step toward recognized guidelines for surface EMG measurement of the adductors. [ABSTRACT FROM AUTHOR]

Background: and Purpose: Hereditary spastic paraplegias (HSP) are a group of clinically diverse genetic disorders that share the neurologic symptom of difficulty in walking due to progressive serious muscle weakness and spasticity in the legs. This study describes a physiotherapy program for improving the functional ability of a child diagnosed with complicated HSP and reports the treatment results. Methods: A 10‐year‐old boy with complicated HSP received a physiotherapy intervention that included strengthening of the leg muscles and treadmill training for 1 h per session, three to four times a week for 6 weeks. Outcome measures included sit‐to‐stand, 10‐m walk, 1‐min walk tests, and gross motor function measures (dimensions D and E). Results: After the intervention, the sit‐to‐stand, 1‐min walk, and 10‐m walk test scores improved by 6.75 times, 2.57 m, and 0.05 m/s, respectively. Furthermore, the gross motor function measure dimensions D and E scores improved by 8% (46%–54%) and 5% (22%–27%), respectively. The gains in each parameter were maintained at the 3‐ and 6‐month and 1‐year follow‐ups. Conclusion: These results suggest that structured physiotherapy programs can benefit the functional rehabilitation of children with complicated HSP. [ABSTRACT FROM AUTHOR]

Introduction: Poliomyelitis has been considered a statutory notifiable infectious disease in Hong Kong since 1948. Approximately 15% to 80% of patients suffer from post-polio syndrome (PPS) with an increased risk of falling and chronic pain. Most of them relied on the use of knee lock-type orthoses as aids. This study aimed to evaluate the effect of using a custom-fit knee robotic orthosis on their gait performance. Materials and Methods: A case series report was used for this study on a group of individuals suffering from chronic PPS who used orthoses and had a history of falling. A knee robotic orthosis was custom-fit for eight sessions of walking practice. Assessments included laboratory gait analysis, functional measures, and subjective ratings of exertional level. Pain responses were recorded to evaluate the effect of using the knee robotic orthosis on participants' gait performance. Results: Five participants completed the study in using the knee robotic orthosis. All achieved reduction in shoulder tilting and trunk swaying movement on walking at the anterior-posterior and the medial-lateral direction. A total of 80% of the study participants achieved reduction in trunk rotation movement, lower-limb circumduction, and hip hiking movement on the affected side on walking. All study participants were able to demonstrate improvement in their gait symmetry after using the knee robotic orthosis as reflected by the symmetric index improvement of kinematics. The rate of perceived exertion and the visual analog scale of pain in all study participants were reported lower when they used the knee robotic orthosis. However, the 10-m walking time achieved was longer. Conclusions: The knee robotic orthosis had a positive effect on remediating the abnormal kinematics of PPS patients using conventional lock-knee orthosis after eight sessions of training practice. Reduction in the limping gait pattern and improvement in gait symmetry was achieved in using a knee robotic orthosis for walking. The chronic pain response and the physical exertional level on walking were also reduced. However, the walking speed achieved was slower. Clinical Relevance: The application of the knee robotic orthosis for walking assist is new to most of the PPS patients. The positive outcomes achieved merit further research for future clinical practice. [ABSTRACT FROM AUTHOR]

Purpose. Sit-to-stand (STS) is functionally more critical for the independency of people with osteoarthritis (OA). During STS, OA people experience a lot of pain from high sagittal torque. This study investigated the effect of toe-out (T-O) and toe-in (T-I) on knee adduction moment (KAM) and knee flexion moment (KFM) during STS in moderate knee osteoarthritis (KOA) and healthy age-matched people. Methods. In this cross-sectional study, 19 volunteers with moderate KOA (KOA group) and 15 age-matched healthy individuals (control group) participated. KAM, KFM, peak times, and terminal knee flexion angle were measured using a motion analysis system during STS in normal foot progression angle (FPA), 10° of T-O, and 10° of T-I. The repeated-measures ANOVA was used to determine the effects of group and FPA condition and their interactions on the knee kinetic and kinematic parameters. Results. T-I reduced the peak KAM significantly in both groups (p = 0.025 and p = 0.05, respectively). Irrespective of the group, T-O and T-I significantly reduced the peak time of KAM and KFM (p = 0.003 and p = 0.035, respectively). People with KOA had significantly higher terminal knee flexion than healthy subjects in all FPA conditions. Conclusions. Ten degrees of toe-in reduced KAM in healthy and KOA people during STS; it may effectively diminish the medial knee contact force in people with KOA. [ABSTRACT FROM AUTHOR]

Background Hip adduction and abduction muscle function plays an important role for risk of groin pain in athletes. Maximal isometric strength can be obtained clinically using a handheld dynamometer. However, in very strong athletes this is challenging, as external fixation of the dynamometer is needed for reliable measures. An alternative to unilateral testing, is the long-lever hip adduction squeeze test and a novel bilateral hip abduction press test. While promising intra-tester reliability has been found for maximal strength during the long-lever hip adduction squeeze test, inter-tester reliability may be more challenging during both maximal and explosive strength measurements. Hypothesis/purpose The aim of the present study was to assess intra- and inter-tester reliability of maximal, and explosive strength during the long lever hip adduction squeeze test and the long lever hip abduction press test in healthy adults using a hand-held dynamometer. Study design Intra- and interrater reliability study. Methods Forty-nine healthy subjects were included for intra- (n=20) and inter-tester reliability (n=29). Subjects performed the hip adduction long lever squeeze test and the bilateral hip abduction press test in a randomized order. Maximal isometric strength and early (0-100 ms) and late (0-200 ms) phase rate of force development (explosive muscle strength) was obtained using a hand-held dynamometer. Relative reliability for all tests was assessed using ICC2,1 two-way mixed model with absolute agreement, thereby taking bias between testers into account. Results Maximal isometric strength showed good intra- and inter-tester reliability for adduction (ICC: 0.93-0.97) and abduction (ICC: 0.88-0.92). For 0-200 ms rate of force development, both the squeeze and press test showed good intra-tester reliability (ICC: 0.85-0.87), whereas inter-tester reliability was good for hip adduction squeeze (ICC: 0.75) and moderate for hip abduction press (ICC: 0.71). For 0-100 ms rate of force development, the hip abduction press test showed good intra-tester reliability (ICC: 0.78). Remaining tests for intra- and inter-tester reliability showed moderate reliability (ICC: 0.50-0.71). Conclusion Assessment of maximal isometric strength in hip adduction squeeze and abduction press test showed good intra- and inter-tester reliability, whereas only 0-200 ms rate of force development demonstrated good intra-tester reliability of both tests. Therefore, rate of force development should preferably be conducted by the same tester, while the long lever squeeze and press test can reliably be used within- and between testers to measure maximal isometric strength. Level of Evidence 3 [ABSTRACT FROM AUTHOR]

Background: Return-to-play (RTP) assessment after anterior cruciate ligament reconstruction (ACLR) rarely includes hip strength. Hypothesis: It was hypothesized that (1) patients after ACLR will have weaker hip abduction (AB) and adduction (AD) strength compared with the contralateral limb, with larger deficits in women, (2) there will be a correlation between hip and thigh strength ratios and patient-reported outcomes (PROs), and (3) hip AB and AD strength will improve over time. Study Design: Descriptive laboratory study. Methods: Included were 140 patients (74 male, 66 female; mean age, 24.16 ± 10.82 years) who underwent RTP assessment at 6.1 ± 1.6 months after ACLR; 86 patients underwent a second assessment at 8.2 ± 2.2 months. Hip AB/AD and knee extension/flexion isometric strength were measured and normalized to body mass, and PRO scores were collected. Strength ratios (hip vs thigh), limb differences (injured vs uninjured), sex-based differences, and relationships between strength ratios and PROs were determined. Results: Hip AB strength was weaker on the ACLR limb (ACLR vs contralateral: 1.85 ± 0.49 vs 1.89 ± 0.48 N·m/kg; P <.001) and hip AD torque was stronger (ACLR vs contralateral: 1.80 ± 0.51 vs 1.76 ± 0.52 N·m/kg; P =.004), with no sex-by-limb interaction found. Lower hip-to-thigh strength ratios of the ACLR limb were correlated with higher PRO scores (r = −0.17 to −0.25). Over time, hip AB strength increased in the ACLR limb more than in the contralateral limb (P =.01); however, the ACLR limb remained weaker in hip AB at visit 2 (ACLR vs contralateral: 1.88 ± 0.46 vs 1.91 ± 0.45 N·m/kg; P =.04). In both limbs, hip AD strength was greater at visit 2 than visit 1 (ACLR: 1.82 ± 0.48 vs 1.70 ± 0.48 N·m/kg; contralateral: 1.76 ± 0.47 vs 1.67 ± 0.47 N·m/kg; P <.01 for both). Conclusion: The ACLR limb had weaker hip AB and stronger AD compared with the contralateral limb at initial assessment. Hip muscle strength recovery was not influenced by sex. Hip strength and symmetry improved over the course of rehabilitation. Although strength differences across limbs were minor, the clinical importance of these differences is still unknown. Clinical Relevance: The evidence provided highlights the need to integrate hip strength into RTP assessments to identify hip strength deficits that may increase reinjury or lead to poor long-term outcomes. [ABSTRACT FROM AUTHOR]

Background: Increased posterior tibial slope (PTS) is a risk factor for knee pathology. Accurate measurement of PTS is predicated on a quality lateral knee radiograph; however, little is known about how the quality of the radiograph affects the measured PTS. Purposes: To (1) describe a method for measuring malalignment on lateral knee radiographs, (2) assess the effects of malpositioning of the knee on radiographic measures of malalignment, and (3) determine any correlations between malalignment and the measured PTS. Study Design: Descriptive laboratory study. Methods: Using a setup similar to that of a standard radiology suite, 25 sets of radiographs were taken using 5 sawbone models. Each set included a true lateral view and separate malpositioned radiographs at 5°, 10°, and 15° of adduction, abduction, internal rotation, and external rotation. Malalignment for each radiograph was quantified as the anterior-posterior distance (APD) and proximal-distal distance (PDD) between femoral condyles. The medial PTS was measured in duplicate, and the interrater reliability was calculated. Results: The interrater reliability was excellent, with intraclass correlation coefficients of 0.92, 0.91, and 0.96 for the APD, PDD, and PTS, respectively. Malrotation significantly affected the APD (P <.001), with a mean change of 5.6 mm per 5°. Malpositioning in abduction/adduction significantly affected the PDD (P <.001), with a mean change of 5.1 mm per 5°. There was no significant impact of rotation or APD on the PTS. Abduction/adduction did affect the PTS (P <.001) above a threshold of 5° of malpositioning. The PTS decreased as the PDD increased, moving from adduction to abduction (R 2 = 0.5687). Conclusion: The measured PTS was more sensitive to malpositioning by abduction/adduction than by malrotation. Malrotation affected the APD, while abduction/adduction affected the PDD. Thus, the accuracy of the measured PTS was compromised more by poorly aligned distal femoral condyles than it was by poorly aligned posterior femoral condyles. Clinical Relevance: To minimize the effects of malpositioning, we recommend utilizing radiographs with a |PDD| of <5 mm and an |APD| of <15 mm when measuring the PTS. [ABSTRACT FROM AUTHOR]

Background: Increased femoral anteversion (IFA) causes functional problems (i.e., tripping, frequently falling, and fatigue) by affecting the pelvis and lower extremity biomechanics. In the frontal plane, increased contralateral pelvic drop and ipsilateral hip adduction, which are mainly considered deteriorated hip abductor muscle mechanisms, are associated with hip and knee injuries. Aims: The aim of this study was to examine the effects of femoral anteversion on hip abductor weakness and frontal plane pelvis–hip biomechanics during walking. Methods: The study included nine subjects with increased femoral anteversion and a control group of eleven subjects. Maximum isometric voluntary contraction (MIVC) values of the hip abductor muscles were measured with a handheld dynamometer. Three-dimensional gait analysis was performed for kinetic, kinematic, and temporo-spatial gait parameters. Non-parametric tests were used for statistical analysis (p < 0.05). Results: There was no significant difference found between the MIVC values of the IFA and control groups (p = 0.14). Moreover, no significant difference was determined between the ipsilateral peak hip adduction (p = 0.088) and contralateral pelvic drop (p = 0.149) in the stance phase. Additionally, there was no correlation between the peak hip adduction angle in the stance phase and normalized MIVC values in the IFA group (r = −0.198, p = 0.44), or in the control group (r = −0.174, p = 0.55). The deviations of pelvic rotation (p = 0.022), hip internal rotation (p = 0.003), and internal foot progression (p = 0.022), were found to be higher in the IFA group than in the controls. Conclusions: IFA may not be associated with hip abductor muscle weakness, and it may not lead to the hip adduction and pelvic depression that can be seen in hip abductor weakness. Increased pelvic rotation and internal hip rotation during walking might be considered as a compensation for the femoral head–acetabulum alignment mechanism in the frontal plane. [ABSTRACT FROM AUTHOR]

Laryngeal carcinomas cause vocal cord (VC) mobility problems. Other than evaluation through flexible laryngoscopy, rare reports concerning CT findings for the motion of the VC or arytenoid cartilage (AC) are found. To explore a novel evaluation of the mobility of the AC in glottic carcinoma. In 39 patients with glottic carcinoma grouped upon lesion locations and AC mobilities, laryngeal CT scans were collected during inspiration and phonation. AC static position and motion data were compared between paired lesion and control sides. No significant difference showed in the group with glottic carcinoma invading the anterior 2/3 of VC. In the abnormal mobility group, significant AC position changes and weaker motion of most measurements were proved on the lesion side. Lesion invading the posterior 1/3 of VC also resulted in an adducted, medially rotated and forward-tilted AC, rotation of axial angle (RAA) was the only motion item that decreased significantly. In most glottic cancer cases, CT and laryngoscope had similar judgments for AC mobility. For lesions extending to the cartilaginous VC with laryngoscopically confirmed normal mobility, CT measurement of RAA showed the feasibility of being an indicator for the earliest motion problem. [ABSTRACT FROM AUTHOR]