Non-dominant Hip Research Articles

Is Wrist Accelerometry Suitable for Threshold Scoring? A Comparison of Hip-Worn and Wrist-Worn ActiGraph Data in Low-Active Older Adults With Obesity.

Hip- and wrist-worn ActiGraph accelerometers are widely used in research on physical activity as they offer an objective assessment of movement intensity across the day. Herein we characterize and contrast key structured physical activities and common activities of daily living via accelerometry data collected at the hip and wrist from a sample of community-dwelling older adults. Low-active, older adults with obesity (age 60+ years) were fit with an ActiGraph GT3X+ accelerometer on their nondominant wrist and hip before completing a series of tasks in a randomized order, including sitting/standing, sweeping, folding laundry, stair climbing, ambulation at different intensities, and cycling at different intensities. Participants returned a week later and completed the tasks once again. Vector magnitude counts/second were time-matched during each task and then summarized into counts/minute (CPM). Monitors at both wear locations similarly characterized standing, sitting, and ambulatory tasks. A key finding was that light home chores (sweeping, folding laundry) produced higher and more variable CPM values than fast walking via wrist ActiGraph. Regression analyses revealed wrist CPM values were poor predictors of hip CPM values, with devices aligning best during fast walking (R2 = 0.25) and stair climbing (R2 = 0.35). As older adults spend a considerable portion of their day in nonexercise activities of daily living, researchers should be cautious in the use of simply acceleration thresholds for scoring wrist-worn accelerometer data. Methods for better classifying wrist-worn activity monitor data in older adults are needed.

The clinical assessment of hip muscle strength in professional rugby union players

Groin/hip injuries are prevalent in rugby union (RU). Assessment of hip muscle strength is important when designing bespoke injury prevention and rehabilitation programmes. ObjectiveThe primary aim of this study was to determine normative values of hip muscle strength in elite-level RU players. A secondary aim of this study was to compare the Copenhagen Hip and Groin Outcome Score (HAGOS) between players with and without a history of groin/hip injury. DesignCross-sectional cohort study. SettingProfessional RU club. Participants58 male professional RU players competing in the PRO14 league elite club level competition. Main outcome measuresHandheld dynamometry eccentric strength values of hip abduction (ABD), adduction (ADD), internal rotation (IR) and external rotation (ER), HAGOS. ResultsPlayers' dominant (DOM) and non-dominant (NDOM) hip strength values were, 2.38 and 2.34 N m/kg for ABD, 2.79 and 2.71 N m/kg for ADD, 2.69 and 2.55 N m/kg for IR, and 2.65 and 2.54 N m/kg for ER. ADD:ABD strength ratio was 1.17 ± 0.26 for the DOM limb and 1.16 ± 0.24 for the NDOM limb. There was no clinically significant difference in strength between players’ DOM and NDOM limbs. Players with a history of groin/hip injury scored lower on four of the HAGOS subscales (pain; symptoms; sport; quality of life) compared to those without a history of groin/hip injury. ConclusionsThis study may help establish normative hip strength and HAGOS values for elite-level RU players. The results presented have important implications for the assessment of hip muscle strength and could provide clinical markers for return-to-play following injury.

Lower extremity injuries in U.S. national fencing team members and U.S. fencing Olympians

ABSTRACT Introduction Fencing is growing rapidly in popularity and competitiveness with fencers beginning at a younger age and competing in more tournaments. Even though fencing has a low risk of time-loss injury, fencers are inevitably going to experience injuries if proper athletic training and prevention does not occur. We aim to describe and compare the lower extremity injuries experienced by fencers that have trained at the highest level in the sport. We hypothesized that athletes who fenced longer would suffer more knee and hip injuries and report lower IKDC and HOS scores. Methods This is an epidemiology study distributed to members of the U.S. national team and Olympic team from 1980 to 2018. The electronic survey included questions regarding age, weapon, number of years fencing, number of national and Olympic teams, injuries on the dominant and nondominant hip and knee, time missed due to injury, and methods for treatment. The survey also included the International Knee Demographic Committee (IKDC) and Hip Outcome Score (HOS). Results There were 153 national team members between July 1980 and July 2018, 110 with contact information. A total of 77 athletes submitted the survey, consisting of 30 females and 47 males. Female fencers had more hip injuries and lower IKDC and HOS scores than their male counterparts. In total, there were 71 injuries to the dominant (front) knee and 28 injuries to the nondominant (back) knee. There were 32 dominant hip injuries and 5 nondominant hip injuries. Saber fencers reported the most dominant and nondominant hip and knee injuries. Conclusion The intense, repetitive and asymmetrical movements involved in fencing affect the weight bearing leg and the nondominant leg in all weapons. Special attention should be paid to female fencers as they experience more hip and knee injuries resulting in impaired joint function.

Effects of equine riding on static and dynamic mechanical contraction of the thighs and trunk muscles in inactive women.

This study investigated whether equine riding affects static or dynamic mechanical contractions on the thighs and trunk muscles in inactive women. Participants consisted of 30 women with a mean (SD) age of 21.06 (0.44) years. They were randomly allotted as follows: equine group (EQG, n= 15) and control group (CON, n= 15). Two types of muscle contraction properties in their thighs and trunk were measured through a tensiomyography (static muscle tester) and an isokinetic device (dynamic muscle tester), respectively. Using the body weights of EQG and CON as covariates, a 2-way between-groups multivariate analysis of covariance was used to investigate group differences in the mechanical quantification of the thighs and trunk. The effectiveness of 8 weeks of equine riding was hardly observed in a static muscle test, whereas in the dynamic muscle test, the dominant and non-dominant hip extensor/flexor, the dominant hip abductor/adductor, and trunk extensor in the EQG showed a significant increase, compared to no changes in the CON. This study did not find any particular differences in a static muscle test in inactive women, but showed improvements in the dynamic mechanical properties of the thighs and trunk, which are major muscle groups related to spinal alignment.

Comparison of Energy Expenditure and Step Count Measured by ActiGraph Accelerometers Among Dominant and Nondominant Wrist and Hip Sites

Objective: To validate and compare the accuracy of energy expenditure (EE) and step counts measured by ActiGraph accelerometers (ACT) at dominant and nondominant wrist and hip sites. Methods: Thirty young adults (15 females, age 22.93 ± 3.30 years) wore four ActiGraph wGT3X accelerometers while walking and running on a treadmill for 7 min at seven different speeds (1.7, 2.5, 3.4, 4.2, 5.0, 5.5, and 6.0 mph). The EE from each ACT was calculated using the Freedson Adult equation, and the “worn on the wrist” option was selected for the wrist data. Indirect calorimetry and manually counted steps were used as criterion measures. Mean absolute percentage error and two one-sided test procedures for equivalence were used for the analyses. Results: All ACTs underestimated the EE with mean absolute percentage errors over 30% for wrist placement and over 20% for hip placement. The wrist-worn ACTs underestimated the step count with mean absolute percentage errors above 30% for both dominant and nondominant placements. The hip-worn ACTs accurately assessed steps for the whole sample and for women and men (p < .001 to .05 for two one-sided tests procedures), but not at speeds slower than 2.0 mph. Conclusion: Neither hip nor wrist placements assess EE accurately. More algorithms and methods to derive EE estimates from wrist-worn ACTs must be developed and validated. For step counts, both dominant and nondominant hip placements, but not wrist placements, lead to accurate results for both men and women.

Predictors of throwing performance in amateur male cricketers: A musculoskeletal approach

Optimal throwing speed and accuracy is built on a complex interaction of multiple variables. Although strength and power has been associated with throwing speed in cricketers, the individual muscles that contribute to optimal function of the shoulder-complex has not been adequately explored in connection with throwing performance. Consequently, this study aimed to investigate the correlation between musculoskeletal variables and overhead throwing performance in cricketers. Thirty-two amateur male cricketers were tested using a battery of 16 tests (strength, flexibility, scapula positioning) as well as a throwing speed (TS) and a novel accuracy test (TA). Only two of the sixteen tests were correlated with throwing performance in the multiple regression analysis. Non-dominant hip abduction strength correlated positively with TS (p < 0.05): on average, a strength increase of 10 newtons (N) was associated with an increase in TS of 0.60 km/h (95% CI: 0.12–1.08). Non-dominant pectoralis minor length correlated positively with TA (p < 0.01): on average, a one-centimetre increase in the length correlated to an increase, of 0.633 points (95% CI: 0.225–1.041). This cross-sectional study demonstrated that from an array of musculoskeletal variables, only non-dominant hip abduction strength correlated with TS, while only non-dominant pectoralis minor length correlated with TA in amateur cricketers.

Accelerometer Cut Points For Adults With Down Syndrome

Past research has indicated that the relationship between energy expenditure and accelerometer output is different between adults with and without Down syndrome (DS). This suggests a need for DS-specific cut points for determining levels of sedentary behavior and physical activity from accelerometer output for adults with DS. PURPOSE: To develop accelerometer output cut points for sedentary behavior and moderate and vigorous intensity physical activity for adults with DS. METHODS: Sixteen adults with DS (10 men & 6 women; age 31 ± 15 years) performed 12 tasks each lasting 6 min: sitting; playing app on tablet; drawing; folding clothes; sweeping; fitness circuit; moving a box; basketball; standing; and walking at the preferred speed and at 0.8 and 1.4 m.s-1. We measured the rate of oxygen uptake with portable indirect calorimetry (K4b2, Cosmed) and expressed it in Metabolic Equivalents (METs). Output from a triaxial accelerometer (wGT3X-BT, Actigraph) worn on the non-dominant hip was determined as Vector Magnitude. Receiver Operating Characteristic (ROC) curves were used to identify Vector Magnitude cut points for sedentary behavior and moderate (3.0 - 5.99 METs) and vigorous (≥6 METs) intensity physical activity. Overall performance of classification models was assessed with the area under the ROC curve. Optimal cut points maximizing sensitivity and specificity were selected based on Youden’s index. RESULTS: Area under the ROC curve was high for all models: (a) sedentary behavior (0.96; 95% CI: 0.93 - 0.98); (b) moderate intensity physical activity (0.92; 95% CI: 0.88 - 0.96); and (c) vigorous intensity physical activity (0.92; 95% CI: 0.85 - 0.99). The optimal Vector Magnitude cut points were: (a) sedentary behavior ≤236 counts·min-1 (sensitivity 0.98; specificity 0.90; Youden’s index 0.88); (b) moderate-intensity physical activity ≤2167 counts·min-1 (sensitivity 0.99; specificity 0.82; Youden’s index 0.81); and (c) vigorous-intensity physical activity ≥4200 counts·min-1 (sensitivity 1.00; specificity 0.84; Youden’s index 0.84). CONCLUSION: This study offers the first DS-specific accelerometer output cut-points for classifying sedentary behavior and intensity of physical activity in adults with DS. Overall classification accuracy was excellent. Supported by NIH Grant R15HD098660

Predicting Oxygen Uptake From Accelerometer Output In Adults With Down Syndrome: Vector Magnitude Vs. Vertical Axis

Adults with Down syndrome (DS) have altered movement patterns. Especially during walking, their altered mediolateral and anteroposterior body motion predicts their elevated energy cost. Triaxial accelerometers provide a metric of three-dimensional acceleration—Vector Magnitude (VM) counts—which may better estimate the rate of oxygen uptake (VO2) during physical activities and sedentary behaviors than the traditionally used Vertical Axis (VA) counts. PURPOSE: To examine if VM counts are more accurate than VA counts in estimating VO2 across different physical activities and sedentary behaviors in adults with DS. METHODS: Sixteen adults with DS (10 men; age 31 ± 15 years) performed 12 tasks: sitting; playing app; drawing; folding clothes; sweeping; fitness circuit; moving box; basketball; standing; and walking at the preferred speed and at 0.8 and 1.4 m.s-1. We measured VO2 with a spirometer (K4b2, Cosmed) and VA and VM with an accelerometer (wGT3X-BT, Actigraph) on the non-dominant hip. We used two separate multi-level regression models to predict VO2 from VA or VM. We evaluated the fit of models with the R2, and accuracy with Bland-Altman plots and absolute percent error which was compared between models across tasks using within-subject (method-by-task) ANOVA and follow-up paired-samples t-tests. RESULTS: Both VM and VA significantly predicted VO2 in separate models (p <0.001; R2 = 0.74 and 0.65, respectively). Across all tasks combined, absolute percent error was lower for the VM than the VA model (23.7 ± 26.2 and 33.6 ± 35.9, respectively). A significant method-by-task interaction in within-subject ANOVA and follow-up t-tests indicated that absolute error was lower for the VM than the VA model for sitting, playing an app, drawing, and standing (p ≤0.004), but did not differ for other tasks. Bland-Altman plots indicated zero mean error for both models; however, the limits of agreement were narrower for the VM than the VA model (-6.44 to 6.44 and -5.57 to 5.57 ml.kg-1.min-1, respectively). CONCLUSION: Both VA and VM counts predict VO2 in adults with DS; however, prediction is more accurate for a VM than a VA model during sedentary behaviors. VM counts should be used in developing accelerometer-based prediction of physical activity and sedentary behavior in adults with DS. Supported by NIH Grant R15HD098660

Judokas with low back pain have lower flexibility of the hip-spine complex: A case-control study

ObjectiveStudy whether male adult judokas with and without low back pain (LBP) have different hip-spine flexibility. DesignCross-sectional. SettingJudo training centres. ParticipantsJudokas with (n = 29) and without (n = 33) LBP. Main outcome measuresRange of motion (ROM) (passive and active rotations) of hips, lumbar spine (flexion-extension) and fingertip-to-floor distance (FTFD). ResultsThe non-dominant hips of judokas with LBP had 6.8 ± 1.2° (ES:1.45, p < 0.001) lower passive and 8.0 ± 1.3° (ES:1.55, p < 0.001) lower active internal rotation. Dominant hips of judokas with LBP had 5.1 ± 1.6° (ES: 0.81, p = 0.002) lower active internal rotation and 8.8 ± 2.9° (ES:0.79, p = 0.003) lower active total rotation. The LBP group showed 8.0 ± 2.8° (ES: 0.73, p = 0.006) lower flexion and 6.0 ± 2.2° (ES: 0.69, p = 0.009) lower extension of the lumbar spine. The FTFD in the LBP group was 7.3 ± 2.6 cm (ES: 0.72, p = 0.007) lower. The multi-level regression analyses showed passive (OR 1.54, 95%CI 1.18–2.00, p = 0.001) and active (OR 1.47, 95%CI 1.16–1.87, p = 0.001) hip internal rotation of the non-dominant leg and lumbar spinal flexion (OR 1.11, 95%CI 1.03–1.20, p = 0.006) and extension (OR 1.16, 95%CI 1.01–1.33, p = 0.035) were related to LBP. ConclusionLower hip internal rotation of the non-dominant leg (passive and active) and lower lumbar flexibility are significantly related to LBP in male adult judokas.

Predicting the rate of oxygen uptake from step counts using ActiGraph waist-worn accelerometers in adults with Down syndrome.

Step rate predicts ambulatory intensity as reflected in the rate of oxygen uptake (VO2 ) - a measure of energy expenditure. Whether step rate as measured by an accelerometer predicts VO2 in adults with Down syndrome (DS) is unknown. We examined whether step rate predicts VO2 in adults with and without DS. We also developed an equation for predicting VO2 and examined its accuracy. Sixteen adults with DS (6 women and 10 men; age 31±15years) and 19 adults without DS (9 women and 10 men; age 25±6years) performed standing and walking at their preferred speed, 0.8 and 1.4m·s-1 . We measured VO2 with a portable spirometer and step rate with a triaxial accelerometer (wGT3X-BT; ActiGraph) on the non-dominant hip, using the low-frequency extension filter. We ran multilevel regression for predicting VO2 from linear and quadratic terms for step rate, group (1=DS; 0=non-DS), body mass, height, body mass index (BMI), leg length and sex. We estimated VO2 with the resultant equation and calculated the equation's absolute per cent error, which we compared between groups. VO2 was higher in persons with than without DS only at the fast walking speed (P=0.018). DS did not predict VO2 . Step rate, step rate squared and BMI were significant predictors of VO2 (P<0.001; R2 =0.80). Absolute error across walking speeds was 13.5-18.8% and 11.7-13.4% for adults with and without DS, respectively, and did not differ between groups or speeds. Step rate, step rate squared and BMI predict VO2 in adults with and without DS. Prediction error does not differ between groups.

Comparison between the Dominant and Non-dominant Sides of Athletes with Groin Pain.

Objective To compare the difference in range of motion (ROM) between the dominant and nondominant hips of the athletes and to correlate the results with groin pain, as well as to compare the differences in ROM among the main hip injuries. Methods The participants included 75 athletes, 56 males and 19 females, aged between 20 and 46 years old, who were diagnosed with hip injury. These individuals were subdivided according to the pathologies (femoroacetabular impact or labral lesion, adductor and pubic lesions and trochanteric syndrome) and characteristics of each hip were analyzed. Results A total of 150 hips (right and left) were measured for the present analysis. When comparing the ROM of the injured hip with the healthy hip, no statistically significant differences were found. There were also no significant differences between the amplitudes of hip movement when the main pathologies were compared. Conclusion The present study did not find differences in ROM rotation between the various pathologies of the hip.

Effects of Hip Muscle Resistance Training With and Without Feedback on Trunk, Pelvis, and Lower Extremity Motions

Introduction: The present study aimed to compare hip muscle resistance training with and without feedback on trunk, pelvis, and lower extremity motions in frontal and sagittal planes among active females with dynamic valgus. Materials and Methods: Twenty-Nine active females (Mean±SD age: 22.8±2.4 years, height: 1.70±0.6 m, weight: 69±7.1 kg) were randomly assigned to a hip muscle resistance training with feedback group (n=15) or a hip muscle resistance training without feedback group (n=14). Both training programs lasted 6 weeks (3 sessions/week). The peak angles of lateral trunk flexion, contralateral pelvic drop, hip flexion, knee flexion, and valgus during single-leg drop landing and single-leg vertical drop jump were assessed in the research participants at baseline and 6 weeks post-training. Unipodal functional screening tests were captured with two standard digital video cameras. Results: After 6 weeks, significant differences were observed in knee valgus and lateral trunk flexion, contralateral pelvic drop, and knee flexion angles, i.e., compared between hip muscle resistance training with feedback and hip muscle resistance training without feedback (P&lt;0.05), except for non-dominant leg hip flexion in single-leg vertical drop jump (P&gt;0.05). Conclusion: In the explored active females with dynamic valgus, hip muscle resistance training with feedback seems to be better at improving trunk, pelvis, and lower extremity motions in frontal and sagittal planes, compared to hip muscle resistance training without feedback; however, no significant difference was observed concerning hip flexion during single-leg vertical drop jump between the study groups.

Treatment of scalene muscles with the Ergon technique can lead to greater improvement in hip abduction range of motion than local hip adductor treatment: a study on deep front line connectivity.

[Purpose] This study aimed to investigate the effects of Ergon® instrument-assisted softtissue mobilization of the upper and lower midpoints of the Deep Front Line (DFL) on hip abduction range of motion (ROM). [Participants and Methods] Forty healthy adults (29.3 ± 6.3 years; height: 175.8 ± 7.4 cm; weight: 77.2 ± 9.2 kg) were randomly divided into two groups and received a single 15-minute Ergon treatment in the upper midpoint (scalene muscles) and the lower midpoint of the DFL (hip adductors) on their dominant side. The non-dominant hip served as a control. Pre-and post-therapy active and passive hip abduction ROM at 0° and 90° flexion was examined using a goniometer. [Results] In both experimental groups, active and passive hip abduction ROM on the treated side improved significantly compared to the control side. Scalene treatment led to significantly greater improvement in active hip abduction ROM at 0° and 90° and in passive ROM at 90° compared to local hip adductor treatment. [Conclusion] The application of the Ergon technique on remote parts of the DFL may lead to a significant increase in hip abduction ROM compared to local hip adductors treatment.

THE IMMEDIATE EFFECTS OF A TOTAL MOTION RELEASE® WARM-UP ON ACTIVE ROTATIONAL HIP RANGE OF MOTION IN OVERHEAD ATHLETES

Reductions in hip range of motion (ROM) correlate with lower extremity injury and alterations in shoulder mechanics in overhead athletes. Such shifts in kinetic-chain dynamics may lead to additional stresses at common injury sites of the upper and lower extremities. Researchers have suggested that Total Motion Release® (TMR®) increases shoulder ROM more effectively than traditional warm-up methods. It is plausible that similar methods may produce increases in ROM at the hip. To explore the effects of a TMR® based intervention on active hip rotational ROM in overhead athletes compared to a traditional athletic warm-up. Randomized Control Trial. Twenty-two secondary school, NCAA Division I, III, and Club student-athlete participants (sex: 13 females, 9 males; sport: 9 javelin, 7 volleyball, 7 baseball; age = 19.3 ± 1.1 years; height = 178 ± 11.4 cm; weight = 76.4 ± 11.2 kg.) were randomly assigned to TMR® (TMRG; n = 11) and traditional warm-up (TWG; n = 11) groups. The TMRG performed three sets of forward flexed trunk twist and seated straight leg raise held for 20 seconds each to the side of ease with a 30-second rest interval. Active hip internal and external rotation was measured using the Clinometer smartphone application immediately before and after intervention. The TMRG experienced significant immediate increases in active dominant hip ER,, active nondominant hip ER, active dominant total hip rotational ROM, and active nondominant total hip rotational ROM (mean change = +6.27°, + 12.2°, + 4.8, and +11.9°), compared to the TWG (mean change = +0°, + 1.9°, -1°, and 1°) respectively. Using TMR® motions and principles as a warm-up produced meaningful changes in active hip rotational ROM bilaterally in overhead athletes. IIb.

Prediction of Energy Expenditure from Pedometer-Determined Step-Rate in Adults with and without Down Syndrome

Electronic pedometers are relatively inexpensive devices to monitor physical activity. To assess physical activity intensity using a pedometer, establishing the relationship between step-rate measured by a pedometer and the rate of oxygen uptake (VO2) is needed. This study examined the step-counting accuracy of the NL-2000i electronic pedometer and whether pedometer-measured step-rate accurately predicts the energy expenditure in adults with and without Down syndrome (DS). Participants were 15 adults with DS and 15 adults without DS. Participants completed three walking trials at: their preferred speed; 0.8 m·s−1; and 1.4 m·s−1. We measured VO2 with a portable open-circuit spirometer and step rate with NL-2000i worn on the non-dominant hip and hand-tally as the criterion. We used multi-level modeling to develop an equation predicting VO2. We computed the absolute percent error of the VO2 prediction equation and the step-counting error of the pedometer. We evaluated differences between groups across speeds for these variables using 2 × 3 (group × speed) two-way analysis of variance. Step-counting error of the NL-2000i was low, but it was higher in adults with than without DS at the preferred and fast walking speeds (p ≤ .029). An equation predicting energy expenditure included step-rate, group, and their interaction (p < .001; R2 = 0.52). The NL-2000i pedometer has high accuracy across speeds. Step-rate measured by NL-2000i predicts energy expenditure with a relatively low error in adults with and without DS.

The acute effect of match-play on hip range of motion and isometric strength in elite tennis players.

BackgroundGroin injuries are some of the most common injuries tennis players suffer. Several factors (e.g., post-match decrease in hip adductor (ADD) strength) have been proposed as possible mechanisms for increasing the incidence of this type of injury. However, the risk factors of developing groin injuries after a tennis match have not yet been delineated.ObjectiveThe aim of this study was to determine the effect of tennis match-play on isometric ADD and abductor (ABD) strength and passive hip range of motion (ROM).MethodsTwenty-six male tennis players (20.30 ± 4.98 years) took part in this study. Participants completed an evaluation of strength and flexibility hip measurements before and after a simulated tennis match. Dominant and non-dominant passive hip ROM, ADD and ABD isometric strength, and the ADD/ABD strength ratio were measured before and immediately post-match. A global positioning system (GPS) and a session rating of perceived exertion (RPE) were used to assess the locomotive demands and internal match load.ResultsIsometric dominant ADD strength (17.8%, p ≤ 0.01) and ADD/ABD strength ratio (11.6%, p = 0.04) were lower post-match compared to the pre-match values. No between-limbs differences were observed for isometric ADD strength, ABD strength, and passive hip ROM tests. RPE showed an expected increase between pre- vs. post-match (pre- vs. post-warming-up, 3.42 ± 2.08 vs. 5.62 ± 2.29, p < 0.01). In addition, a significant relationship between ADD strength and the volume of tennis practice per week was found, stablishing that tennis players with lower volume of training per week suffered a reduction in ADD strength in their dominant limb after match-play (r = 0.420, p = 0.04).ConclusionThe assessment of ADD strength and the ADD/ABD strength ratio in the dominant limb may be considered a post-match tool that can be used to identify players who require rest and additional recovery strategies before competing again.

Shoulder Pain and Rotational Range of Motion of the Trunk, Shoulder, and Hip in Baseball Players.

Deficient glenohumeral rotational range of motion (ROM) is a risk factor for shoulder pain. Adapted ROM of the trunk and hip in response to loss of glenohumeral ROM has been suggested, as the nature of baseball leads to ROM adaptations. To compare the bilateral rotational ROM values of the trunk and glenohumeral and hip joints in adolescent baseball players with or without shoulder pain and to measure the correlation between shoulder-pain intensity and bilateral rotational ROM values for each body area. Cross-sectional study. Research laboratory. Ninety-five adolescent baseball players (60 with shoulder pain, 35 without shoulder pain). Bilateral trunk rotation and internal rotation, external rotation, and total rotation of the dominant and nondominant glenohumeral and hip joints. Glenohumeral and hip ROM did not differ between groups, and pain intensity and rotational ROM were not related in either joint. Trunk rotational ROM was greater in the pain group than in the control group (dominant side = 48.8° ± 14.2° versus 41.8° ± 11.9°, respectively; nondominant side = 45.1° ± 14.2° versus 38.9° ± 7.7°, respectively; P values < .05), although the difference was clinically small (mean differences = 7.0° ± 2.7° [95% confidence interval = 1.7, 12.4] on the dominant side, P = .01, and 6.1° ± 2.7° [95% confidence interval = 0.8, 11.5] on the nondominant side, P = .03). Positive but low correlations in all players (ρ = 0.27, P = .01) and in those with shoulder pain (ρ = 0.36, P = .001) were present between shoulder-pain intensity and trunk rotational ROM toward the dominant side. We found no clinical relationship between shoulder pain and rotational ROM and no clinical differences in rotational ROM values between players with and those without shoulder pain.

Sex differences in lower extremity musculoskeletal and neuromuscular characteristics in intercollegiate soccer athletes

ABSTRACTPurpose: Establishing sex-specific musculoskeletal characteristics promotes specific and effective injury prevention. The purpose was to identify sex differences in musculoskeletal characteristics in soccer athletes.Methods: 80 collegiate male and female soccer athletes participated. Flexibility included: weight-bearing ankle dorsiflexion mobility (DFM), active ankle dorsiflexion (ADF), active knee extension (AKE), and passive hip flexion (PHF). Strength tests included: ankle dorsiflexion/inversion/eversion, knee flexion/extension, hip abduction/adduction/internal/external rotation. LE dynamic postural stability (DPS) was assessed with an accelerometer. DPS was expressed as the Dynamic Postural Stability Index composite (DPSIC) and component scores in the anterior/posterior (APSI), medial/lateral (MLSI), and vertical (VSI) directions. If normally distributed, differences were calculated using a Student’s T-test; if non-normal, a Mann–Whitney U test was utilized.Results: Flexibility tests yielded significant differences for AKE (Dominant:p = 0.008, Non-Dominant:p = 0.040) and PHF (Dominant:p < 0.000,Non-Dominant:p = 0.001). Strength tests yielded significant differences for non-dominant hip internal rotation (p = 0.002). Dynamic postural stability tests yielded significant differences for DPSIC (p = 0.0160) and APSI (p = 0.014).Conclusion: These results implicate that flexibility and DPS may be better linked to sex than strength, suggesting that they may sex-specific musculoskeletal characteristics for the purpose of effective injury prevention.

Dominant vs. non-dominant hip comparison in bone mineral density in young sporting athletes

SummaryTo explore differences in bone mineral density (BMD) between dominant and non-dominant hip within levels of sport impact. BMD was higher in the non-dominant hip in high-impact sports, whereas the dominant hip had increased BMD for low-impact sports. The side-to-side differences were relatively small and not clinically relevant.PurposeIt is unknown whether there is difference in BMD at the hip between dominant and non-dominant sides in young athletes. The aims of this study were to explore the dominant–non-dominant differences in hip BMD in young athletes participating in low- and high-impact sports and to assess the effect of ground force impact on BMD.MethodsData was collected on University of Oxford athletes and controls (CG) between 2016 and 2018. Athletes were classified into two groups: high-impact sports (HIG) and low-impact sports (LIG). Total and regional measurements of both hips’ BMD were recorded using a dual-energy X-ray absorptiometry (DXA). Linear regression method was used to assess differences in BMD between and within groups.ResultsOne hundred ninety-four athletes (HIG: n = 89, LIG: n = 105) and 48 controls were included in this study. Total hip and femoral neck BMD was higher in athletes compared to the CG (p < 0.01), with HIG recording highest levels of BMD. The BMD difference between the dominant and non-dominant sides was significant in the LIG, with BMD being higher in the dominant side. Conversly, BMD was higher in the non-dominant hip within the HIG. However, the hip asymmetries were not clinically relevant (%BMD difference < 3%). A significant interaction between side and sport group on BMD was observed.ConclusionsHigh-impact sports had significantly higher BMD compared with low-impact sports and CG. BMD in the dominant hip was significantly higher for the LIG and lower in the HIG; however, differences were not clinically relevant.

Predictors of fragility fracture and low bone mineral density in patients with a history of parental fracture

ObjectivesBone mineral density (BMD) and fragility fracture (FF) have high heritability, but few data exist on impact of other factors on families with fracture history. We aimed to evaluate predictors of FF and low BMD, in patients with family history of FF. MethodsThis was a retrospective study on patients undergoing dual energy X-ray absorptiometry at a district general hospital (DGH), 2004–2016. Parameters recorded (in addition to standard dual energy X-ray absorptiometry parameters): age, smoking, alcohol, corticosteroids, aromatase inhibitors, Depo-Provera, hormone replacement therapy, rheumatoid arthritis, polymyalgia rheumatica, breast or prostate cancer, coeliac disease, and fracture site. Logistic regression was used to model fracture risk and site, and linear regression for impact of factors on L1–4 and femoral BMD. Factor analyses with polychoric correlation matrices and calculation of Eigenvalues were applied to determine association between fracture sites and associated risk factors. ResultsA total of 6053 patients were included, 91.1% female. 2094 had sustained at least one FF. Smoking, alcoholism, increased age, height, and fat mass increased FF risk. Sites analysed: femur, tibia/fibula, humerus, forearm, ribs, and vertebrae. Alcoholism, and increasing tissue thickness and fat mass significantly increased FF risk. Decreased right femoral and vertebral BMD increased overall FF risk. ConclusionsOur study confirms the effect of certain factors on vertebral BMD, but suggests a differential effect on the upper and lower spine, as well as in the dominant and nondominant hip. Different sites of fracture are associated with different risk factors, the most common sites of fracture being the peripheral long bones and vertebrae.