bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Tibial Rotation on the Presence of Instability in the Anterior Cruciate Ligament Deficient Knee
Authors: Samukawa Mina , Magee David , Katayose Masaki
Published: August 2016

Context:

The effects of tibial rotation after ACL injury have not yet been well determined.

Objective:

To show whether clinical outcomes such as the amount of tibial rotation can affect functional outcomes in normal and ACL deficient knees.

Design:

Case control study.

Setting:

Research laboratory.

Participants:

Twenty normal subjects (Control) and 20 subjects with ACL deficient knees (ACL).

Main Outcome Measures:

Tibial rotation at 30 and 90 degrees of knee flexion was measured using an inclinometer. One-legged hop, crossover hop, figure-of-eight running and 10-m running tests were used and determined the effect(s) of tibial rotation on the outcome of the functional tests.

Results:

There were significant between-group differences in internal and external rotation. The relationship between external tibial rotation and the figure-of-eight index was significantly negatively correlated.

Conclusions:

The amount of tibial rotation is greater in ACL ruptured knees than in uninjured knees, and these greater amounts of tibial rotation affected the figure-of-eight running index.
Fauls Stretching Routine Produces Acute Gains in Throwing Shoulder Mobility in Collegiate Baseball Players
Authors: Sauers Eric , August Anna , Snyder Alison
Published: August 2016

Context:

Stretching prior to activity or as a rehabilitative intervention may promote increased throwing shoulder range of motion (ROM) in baseball pitchers.

Objective:

To evaluate the acute effects of Fauls modified passive stretching routine on throwing shoulder mobility in collegiate baseball players.

Design:

Repeated measures.

Setting:

Laboratory.

Participants:

Thirty collegiate baseball players with unimpaired shoulders.

Interventions:

Fauls modified passive stretching routine was performed on the throwing shoulder of each subject.

Outcome Measures:

Shoulder complex and passive isolated glenohumeral internal and external rotation ROM were measured with a goniometer, and posterior shoulder tightness was assessed with the Tyler’s test method using a carpenter’s square. Measurements were made bilaterally.

Results:

The dominant shoulder displayed significant increases in glenohumeral and shoulder complex internal and external rotation ROM and significantly decreased posterior shoulder tightness following the stretching routine.

Conclusion:

Application of the Fauls modified passive shoulder stretching routine results in acute gains in throwing shoulder mobility of collegiate baseball players.
Return to Exercise Training after Heat Exhaustion
Authors: Armstrong Lawrence E. , Lopez Rebecca M.
Published: August 2016

Context:

Exertional heat exhaustion (HEX) is the most common form of heat illness experienced by athletes, laborers, and military personnel. Both dehydration stemming from a water and/or salt deficiency and a high ambient temperature must exist for HEX to occur. In the field, appropriate therapy can reduce recovery time.

Objective:

This manuscript provides clinical guidance regarding return to activity. The primary focus of this paper is to describe the evaluation of residual effects and the underlying personal characteristics that initially predispose the athlete to HEX. Attention to these factors will reduce the risk of future episodes.
Heart Rate Variability before and after Knee Surgery in Amateur Soccer Players
Authors: Olivier Nicolas , Legrand Renaud , Rogez Jacques , Gamelin FX , Berthoin Serge , Weissland Thierry
Published: August 2016

Objective:

To analyze the consequences on heart rate variability (HRV) of a hospitalization period due to surgery of the knee in sportsmen.

Patients:

Ten soccer players who had undergone knee surgery took part in this study.

Design:

HRV was measured before and after hospitalization within a 7-day interval.

Results:

After the hospitalization phase, heart rate at rest increased significantly (3 beats/minute). A significant decrease of 7% in the cardiac inter beat interval (R-R interval), P < 0.05 and a 66% decrease in total power spectral density: −66%, P < 0.05 were observed. The disturbance of the autonomic nervous system could be due to a variation in cardiac vagal activity resulting in a 64% decrease in the high frequencies (P < 0.05). This variation was not associated with a modification in normalized markers (LFn.u., HFn.u.) and LF/HF ratio (P > 0.05).

Conclusion:

In sportsmen, a hospitalization period led to an increase in resting heart rate and was associated with a disturbance of the autonomic nervous system.
The Relationship between Grading and Instrumented Measurements of Anterior Knee Joint Laxity
Authors: Hurley Wendy L. , Denegar Craig , Buckley William E.
Published: August 2016

Context:

The relationship between clinical judgments of anterior knee laxity and instrumented measurement of anterior tibial translation is unclear.

Objective:

To examine the relationship between certified athletic trainers’ grading of anterior knee laxity and instrumented measurements of anterior tibial translation.

Design:

Randomized, blinded, clinical assessment.

Setting:

Laboratory.

Participants:

Model patients receiving evaluation of anterior knee laxity.

Intervention:

Twelve model patients were evaluated using a MEDmetric® KT1000™ knee ligament Arthrometer® to establish instrumented measurements of anterior translation values at the tibio-femoral joint. Twenty-two certified athletic trainers were provided with operational definitions of potential laxity grades and examined the model patients to make judgments of anterior knee laxity.

Main Outcome Measures:

Correlation between clinical judgments and instrumented measurements of anterior tibial translation.

Results:

Clinical judgments and instrumented measurements were mutually independent.

Conclusions:

Anterior tibial translation grading by certified athletic trainers should be interpreted with caution during clinical decision-making.
Subcutaneous Tissue Thickness Alters the Effect of NMES
Authors: Miller Michael G. , Cheatham Christopher C. , Holcomb William R. , Ganschow Rosealin , Michael Timothy J. , Rubley Mack D.
Published: August 2016

Context:

No direct research has been conducted on the relationship between subcutaneous tissue thickness and neuromuscular electrical stimulation (NMES).

Objective:

The purpose of this study was to determine the effects of subcutaneous tissue thickness on NMES amplitude and NMES force production of the quadriceps.

Design:

Simple fixed design, testing the independent variable of subcutaneous thickness (skinfold) groups with the dependent variables of NMES amplitude and force production.

Setting:

Athletic Training Laboratory.

Participants:

29 healthy women.

Intervention:

NMES to produce at least 30% of maximal voluntary isometric contractions (MVIC) of the quadriceps.

Main Outcome Measure:

Maximal NMES amplitude and percentage of MVIC using NMES.

Results:

A significant skinfold category difference F2,28 = 3.92, P = .032 on NMES amplitude was found. Post hoc revealed the thinnest skinfold category tolerated less amplitude compared to the thickest category. A significant correlation was found between NMES amplitude skinfold category R = .557, P = .002.

Conclusion:

Higher NMES amplitudes are needed for the thickest skinfold category compared to the thinnest skinfold category.
Contribution of the Multifidus Muscle for Control of Upright Posture in Subjects with Spina Bifida Occulta
Authors: Chang Shin-Tsu , Ku Chih-Hung , Hsieh Ming-Fu , Chen Liang-Cheng , Chu Heng-Yi , Chang Cheng-Chiang , Tsai Kao-Chung
Published: August 2016

Context:

The multifidus muscle plays a role in controlling lumbosacral position and postural sway. One of its attachment sites is the exact site of spina bifida occulta (SBO).

Objective:

To investigate the role of the muscle for postural control in SBO.

Design:

Cross-sectional cohort.

Participants:

Eighty subjects with SBO (38 in minor; 42 in major) and controls.

Interventions:

N/A.

Main Outcome Measures:

Subjects stood upright on a platform at 0° and on an inclined surface (10° and 20°) with feet in plantarflexion/dorsiflexion, together with eyes open and closed. The platform system measured posture to obtain sway area and sway mean for statistics.

Results:

Upon sway area/mean, the group differences of major/minor SBO vs. control were all significant. Sway means of minor SBO were lower than those of major SBO at corresponding inclined degrees.

Conclusions:

Subjects with SBO demonstrated increased sway as compared to controls.
Reliability of a Digital-Photographic-Goniometric Method for Coronal-Plane Lower Limb Measurements
Authors: Moncrieff Matthew J. , Livingston Lori A.
Published: August 2016

Context:

Structural and coronal-plane-alignment characteristics of the lower limb are frequently cited as factors contributing to knee pathologies.

Objective:

The purpose of this study was to determine the accuracy and reliability characteristics of a digital-photographic-goniometric method (DPGM) of measurement for 2-dimensional (2D) coronal-plane lower limb measurements of the quadriceps (Q) angle, tibiofemoral (TF) angle, and femur length in human participants adopting a self-selected- or Romberg-stance position.

Design:

Reliability study.

Setting:

University motion-analysis laboratory.

Participants:

A convenience sample of 20 healthy young adult men and women.

Main Outcome Measures:

Intraclass correlation coefficients (ICCs), 95% confidence intervals, and standard error of the measurements.

Results:

Intratester- and intertester-reliability coefficients for the Q angle (ICCs .458–845 and .257–737) were consistently lower than those for the TF angle (ICCs .627–.904 and .700–.839) or femur length (ICCs .867–.958 and .866–.944). Q angles were also significantly larger (13.4%) in the Romberg- vs self-selected-stance position (P < .001) and larger (20.2%) in the left limb than the right limb.

Conclusions:

The DPGM has the potential to produce accurate and reliable measurements of selected 2D lower limb measures. However, the reliability characteristics depend on the ability of the testers to correctly and repeatably landmark the anatomical sites used to define the measurements of interest and might be influenced by other factors such as the stance position adopted, the complexity of the variable (ie, number of anatomical landmarks and segments), and the size of the captured image. Further investigation of these latter factors is warranted.
Evaluating Patellar Kinematics Through Magnetic Resonance Imaging During Open- and Closed-Kinetic-Chain Exercises
Authors: Felicio Lílian Ramiro , Saad Marcelo Camargo , Liporaci Rogério Ferreira , Baffa Augusto do Prado , Santos Antônio Carlos dos , Bevilaqua-Grossi Débora
Published: August 2016

Purpose:

To evaluate patellar kinematics of volunteers without knee pain at rest and during isometric contraction in open- and closed-kinetic-chain exercises.

Methods:

Twenty individuals took part in this study. All were submitted to magnetic resonance imaging (MRI) during rest and voluntary isometric contraction (VIC) in the open and closed kinetic chain at 15°, 30°, and 45° of knee flexion. Through MRI and using medical e-film software, the following measurements were evaluated: sulcus angle, patellar-tilt angle, and bisect offset. The mixed-effects linear model was used for comparison between knee positions, between rest and isometric contractions, and between the exercises.

Results:

Data analysis revealed that the sulcus angle decreased as knee flexion increased and revealed increases with isometric contractions in both the open and closed kinetic chain for all knee-flexion angles. The patellar-tilt angle decreased with isometric contractions in both the open and closed kinetic chain for every knee position. However, in the closed kinetic chain, patellar tilt increased significantly with the knee flexed at 15°. The bisect offset increased with the knee flexed at 15° during isometric contractions and decreased as knee flexion increased during both exercises.

Conclusion:

VIC in the last degrees of knee extension may compromise patellar dynamics. On the other hand, it is possible to favor patellar stability by performing muscle contractions with the knee flexed at 30° and 45° in either the open or closed kinetic chain.
Change in Glenohumeral Rotation and Scapular Position After Competitive High School Baseball
Authors: Thomas Stephen J. , Swanik Kathleen A. , Swanik Charles “Buz” , Huxel Kellie C. , Kelly John D.
Published: August 2016

Context:

Pathologies such as anterior instability and impingement are common in baseball and have been linked to decreases in internal rotation (IR) and concurrent increases in external rotation (ER). In addition, alterations to scapular position have been identified in this population, but the chronology of these adaptations is uncertain.

Objectives:

To determine whether there is a change in range of motion and scapular position after a single baseball season.

Design:

Prospective cohort.

Setting:

High school.

Participants:

19 high school baseball players (age 16.6 ± 0.8 y, mass 78.6 ± 12.0 kg, height 180.3 ± 6.2 cm).

Interventions:

Subjects were measured for all dependent variables at preseason and postseason.

Main Outcome Measures:

Participants were measured for glenohumeral (GH) IR and ER with the scapula stabilized. Total GH range of motion was calculated as the sum of IR and ER. Scapular upward rotation was measured at 0°, 60°, 90°, and 120° of GH abduction in the scapular plane, and scapular protraction, at 0°, hands on hips, and 90° of GH abduction.

Results:

Overall, the dominant arm had significantly less GH IR (11.4°, P = .005) and significantly more ER (4.7°, P = .001) than the nondominant arm. Total motion in the dominant arm was significantly less than in the nondominant arm (6.7°, P = .001). Scapular upward rotation in the dominant arm significantly increased at 0° (2.4°, P = .002) and significantly decreased at 90° (3.2°, P = .001) and 120° (3.2°, P < .001) of abduction from preseason to postseason. Scapular protraction in the nondominant arm significantly decreased at 45° (0.32 cm, P = .017) and 90° (0.33 cm, P = .006) from preseason to postseason.

Conclusion:

These data suggest that scapular adaptations may be acquired over a relatively short period (12 wk) in a competitive baseball season. Competitive high school baseball players also presented with significant GH motion differences between their dominant and nondominant arms. Total motion was also significantly less in the dominant arm than in the nondominant arm.
Reliability of Measuring Humeral Retroversion Using Ultrasound Imaging in a Healthy Nonthrowing Population
Authors: Yoshida Makoto , Saho Yasuaki , Katayose Masaki
Published: August 2016

Context:

Studies have reported the difference in humeral retroversion (HR) between the dominant and nondominant side in throwing athletes. However, there are few data concerning HR for the rest of the population. In addition, the relationship between HR and external (ER) and internal rotation (IR) at 90° shoulder abduction has not been thoroughly investigated.

Objectives:

To investigate the reliability of ultrasound methodology to measure HR. In addition, using ultrasonography, the authors compare HR between the dominant and nondominant sides in healthy adult men and determine the relationship between HR and ER and IR at 90° of shoulder abduction.

Design:

Descriptive study.

Setting:

Laboratory.

Participants:

Thirty-seven healthy male subjects (age 21.9 ± 2.4 y, height 172.9 ± 5.3 cm, weight 66.0 ± 7.2 kg) with no history of shoulder or elbow injury, recruited from a convenience sample, volunteered for the study.

Main Outcome Measures:

Subjects were bilaterally examined for HR, ER, and IR. HR was measured by ultrasonography.

Results:

The intrarater reliability of the ultrasound methodology was .91−.98, and the interrater reliability was .97. The HR angle on the dominant side (mean ± SD: 68.5° ± 10.0°) was significantly greater than that of the nondominant side (58.0° ± 8.4°; P < .001). ER on the dominant side was significantly greater than on the nondominant side (P < .001), whereas IR on the dominant side was significantly smaller than on the nondominant side (P < .001). Total arc of motion for the dominant side was not significantly different from that of the nondominant side (P = .335).

Conclusion:

In the current study, ultrasound methodology to measure HR showed high interrater reliability, as well as high intrarater reliability. In addition, this study indicates that healthy Japanese adult men have side-to-side differences in HR.
Health-Related Quality of Life Differs Between Adolescent Athletes and Adolescent Nonathletes
Authors: Snyder Alison R. , Martinez Jessica C. , Bay R. Curtis , Parsons John T. , Sauers Eric L. , McLeod Tamara C. Valovich
Published: August 2016

Context:

Patient-oriented outcome measures such as the Medical Outcomes Short Form (SF-36) and the Pediatric Outcomes Data Collection Instrument (PODCI) are important tools for determining the impact of events like sport-related injury on health-related quality of life (HRQoL). Unfortunately, there are no published studies using these instruments that compare adolescent athletes with their nonathlete peers, making interpretations of these measures in this population difficult.

Objective:

To compare HRQoL in adolescent athletes and nonathletes using 2 common instruments.

Design:

Cross-sectional.

Setting:

7 high schools.

Participants:

219 athletes and 106 nonathletes.

Intervention:

None.

Main Outcome Measures:

The SF-36 and the PODCI were completed in a counterbalanced manner during 1 session. Dependent variables included the 8 subscale and 2 composite scores of the SF-36 and the 5 subscale scores and 1 global score of the PODCI.

Results:

On the SF-36, athletes reported higher scores on the physical function, general health, social functioning, and mental health subscales and the mental composite score and lower scores on the bodily pain subscale than nonathletes. On the PODCI, athletes reported higher scores on the sport and physical function and happiness subscales and lower scores on the pain/comfort subscale.

Conclusions:

Athletes reported higher scores on a number of SF-36 and PODCI subscales related to mental, emotional, and physical well-being than nonathletes. Our findings suggest that athletic involvement may be a benefit to the overall health status of adolescents and imply that athletes may be a distinct adolescent group requiring their own normative values when using the SF-36 and PODCI.
Comparative Effects of 6-Week Balance, gluteus Medius Strength, and Combined Programs on Dynamic Postural Control
Authors: Leavey Vincent J. , Sandrey Michelle A. , Dahmer Greg
Published: August 2016

Context:

There are few outcomes-based studies that address hip strategy and gluteus medius strength (GMS) for maintaining dynamic postural control.

Objective:

To determine whether GMS training, proprioception training, or a combination of the 2 has an effect on dynamic postural control.

Design:

Pretest-posttest, repeated measures.

Setting:

Sports-medicine clinic.

Participants:

48 healthy male and female college students obtained via sample of convenience.

Interventions:

Three 6-wk programs including exercises for proprioception, GMS, and combined.

Main Outcomes Measures:

Eight Star Excursion Balance Test (SEBT) reach distances and GMS for the dominant leg.

Results:

There was no significant difference between groups. The combination group demonstrated the most improvements in SEBT reach distances, whereas the GMS group demonstrated the most improvement in GMS.

Conclusion:

Use of exercises for proprioception, GMS, or a combination of the 2 will help improve dynamic postural control in healthy, active individuals.
Paraspinal Muscle Activity During Symmetrical and Asymmetrical Weight Training in Idiopathic Scoliosis
Authors: Schmid Annina B. , Dyer Linda , Böni Thomas , Held Ulrike , Brunner Florian
Published: August 2016

Context:

Various studies report decreased muscle activation in the concavity of the curve in patients with scoliosis. Such decreased muscle-performance capacity could lead to sustained postural deficits.

Objective:

To investigate whether specific asymmetrical sports therapy exercises rather than symmetrical back strengthening can increase EMG amplitudes of paraspinal muscles in the concavity of the curve.

Design:

Cross-sectional.

Setting:

Laboratory.

Participants:

16 patients with idiopathic scoliosis.

Interventions:

Patients performed 4 back-strengthening exercises (front press, lat pull-down, roman chair, bent-over barbell row) during 1 test session. Each exercise was performed in a symmetrical and asymmetrical variant and repeated 3 times.

Main Outcome Measure:

EMG amplitudes of the paraspinal muscles were recorded in the thoracic and lumbar apexes of the scoliotic curve during each exercise. Ratios of convex- to concave-side EMG activity were calculated.

Results:

Statistical analysis revealed that the asymmetrical variants of front press at the lumbar level (P = .002) and roman chair and bent-over barbell row at the thoracic level (P < .0001, .001 respectively) were superior in increasing EMG amplitudes in the concavity of the scoliotic curve.

Conclusions:

Specific asymmetrical exercises increase EMG amplitudes of paraspinal muscles in the concavity. If confirmed in longitudinal studies measuring improvements of postural deficits, these exercises may advance care of patients with scoliosis.
Low Back Pain in Athletes
Authors: Kahler David M.
Published: August 2016

The complaint of persistent low back pain in an athlete is usually related to an identifiable structural disorder. As with all other medical conditions, effective treatment relies on an accurate diagnosis. Certain sporting activities are associated with characteristic acquired lesions; this knowledge, when combined with a thorough history and physical examination, will often dictate when the clinician should refer an athlete for further testing. Most causes of back pain in athletes can be treated nonsurgically if they are identified early and treated appropriately. The common congenital abnormalities, acquired conditions, and overuse syndromes causing low back pain in athletes will be discussed, along with appropriate diagnostic tests and treatment regimens.
Hormonal Ergogenic Aids
Authors: Rogol Alan D.
Published: August 2016

Most hormonal agents used for nonmedical purposes in athletes have legitimate medical uses. This review introduces each compound by its pharmacology, clinical pharmacology, and legitimate medical use and reviews information on its abuse. Human growth hormone is presently available in virtually unlimited quantities due to its production by recombinant DNA technology. Its use in athletes is considered for its muscle-building, fat-depleting properties. Erythropoietin is a kidney hormone that increases red cell mass. It is used for renal dialysis patients to avoid blood transfusions. Its use in athletes is to raise red blood cell mass in an attempt to augment maximal oxygen capacity and the ability to do endurance work. Human chorionic gonadotropin has the biological activity of luteinizing hormone to increase testosterone synthesis and to maintain (partially) testicular volume when exogenous androgens are taken. Clenbuterol is a beta2adrenergic agonist with muscle-building properties that are seemingly specific to striated muscle; clenbuterol may cause reduction in body fat.
Fracture of the First Rib in a Collegiate Soccer Player
Authors: Fruh Jean M.
Published: August 2016

This paper discusses the case of an 18-year-old collegiate soccer player who developed right shoulder and scapular pain following a preseason practice session. Initial evaluation revealed tenderness of the right trapezius muscle but no swelling, deformity, loss of range of motion, or neurological signs. Subsequent radiographic examination revealed a fracture of the first rib. Although uncommon in sports, a nontraumatic fracture of the first rib may result from a sudden violent contraction of the scalenus anterior muscle. Symptoms of a first rib fracture include an acute, knifelike pain in the anterior neck, a dull ache in the shoulder or scapular region, a “snapping” sensation in the shoulder, and possible neurological symptoms due to involvement of the brachial plexus. Proper care includes application of ice, use of a sling for immobilization, and careful attention to the possibility of complications. Rehabilitation consists of a gradual range of motion and strengthening program.
Gluteus Medius Muscle Activation During Isometric Muscle Contractions
Authors: O’Dwyer Catriona , Sainsbury David , O’Sullivan Kieran
Published: August 2016

Context:

Functional subdivisions are proposed to exist in the gluteus medius (GM) muscle. Dysfunction of the GM, in particular its functional subdivisions, is commonly implicated in lower limb pathologies. However, there is a lack of empirical evidence examining the role of the subdivisions of the GM.

Objectives:

To compare the activation of the functional subdivisions of the GM (anterior, middle, and posterior) during isometric hip contractions.

Design:

Single-session, repeated-measures observational study.

Setting:

University research laboratory.

Participants:

Convenience sample of 15 healthy, pain-free subjects.

Intervention:

Subjects performed 3 maximal voluntary isometric contractions for hip abduction and internal and external rotation on an isokinetic dynamometer with simultaneous recording of surface electromyography (sEMG) activity of the GM subdivisions.

Main Outcome Measures:

sEMG muscle activity for each functional subdivision of the GM during each hip movement was analyzed using a 1-way repeated-measures ANOVA (post hoc Bonferroni).

Results:

The response of GM subdivisions during the 3 different isometric contractions was significantly different (interaction effect; P = .003). The anterior GM displayed significantly higher activation across all 3 isometric contractions than the middle and posterior subdivisions (main effect; both P < .001). The middle GM also demonstrated significantly higher activation than the posterior GM across all 3 isometric contractions (main effect; P = .027). There was also significantly higher activation of all 3 subdivisions during both abduction and internal rotation than during external rotation (main effect; both P < .001).

Conclusions:

The existence of functional subdivisions in the GM appears to be supported by the findings. Muscle activation was not homogeneous throughout the entire muscle. The highest GM activation was found in the anterior GM subdivision and during abduction and internal rotation. Future studies should examine the role of GM functional subdivisions in subjects with lower limb pathologies.
The Effect of Gender on Foot Anthropometrics in Older People
Authors: de Castro Alessandra Paiva , Rebelatto José Rubens , Aurichio Thaís Rabiatti
Published: August 2016

Context:

Some questions remain regarding the anthropometric differences between the feet of young men and women, but the gap is much greater when dealing with older adults. No studies were found concerning these differences in an exclusively older adult population, which makes it difficult to manufacture shoes based on the specific anthropometric measurements of the older adult population and according to gender differences.

Objective:

To identify differences between the anthropometric foot variables of older men and women.

Design:

Cross-sectional.

Participants:

154 older women (69.0 ± 6.8 y) and 131 older men (69.0 ± 6.5 y).

Main Outcome Measures:

The foot evaluations comprised the variables of width, perimeter, height, length, 1st and 5th metatarsophalangeal angles, the Arch Index (AI), and the Foot Posture Index (FPI). A data analysis was performed using t test and a post hoc power analysis.

Results:

Women showed significantly higher values for the width and perimeter of the toes, width of the metatarsal heads, and width of the heel and presented significantly lower values for the height of the dorsal foot after normalization of the data to foot length. The 1st and 5 th metatarsophalangeal angles were smaller in the men. There were no differences between men and women with respect to AI and FPI.

Conclusions:

Overall, the current study shows evidence of differences between some of the anthropometric foot variables of older men and women that must be taken into account for the manufacture of shoes for older adults.
Difference in Response Latency of the Peroneus Longus Between the Dominant and Nondominant Legs
Authors: Knight Adam C. , Weimar Wendi H.
Published: August 2016

Context:

The latency of the peroneus longus in response to an inversion perturbation is a key component in the prevention of lateral ankle sprains. In addition, the dominant ankle is sprained more frequently than the nondominant ankle, but the cause of this has not been examined.

Objective:

To investigate the combination of these 2 research-supported statements, the purpose of this study was to use an inversion perturbation that replicates the mechanism of a lateral ankle sprain to determine whether there is a difference in the latency of the peroneus longus between the dominant and nondominant legs.

Design:

Repeated-measures single-group design.

Setting:

University laboratory.

Participants:

15 physically active healthy volunteers with no previous history of an ankle sprain or lower extremity surgery or fracture.

Interventions:

Outer sole with fulcrum was used to cause 25° of inversion at the subtalar joint on landing from a 27-cm step-down task. Participants performed 10 trials on both the dominant and nondominant leg.

Main Outcome Measures:

2 latency measures of the peroneus longus of both the dominant and nondominant leg, calculated as the amount of time from the moment of touchdown of the fulcrum until muscle activity exceeded 5 and 10 SD above baseline muscle activity.

Results:

The latency of the peroneus longus of the nondominant leg was significantly shorter when using both 5 SD (F1,14 = 9.34, P = .009, d = .895) and 10 SD (F1,14 = 18.56, P = .001, d = .920) above baseline muscle activity.

Conclusions:

This difference in latency may be a result of the different demands placed on the dominant and nondominant legs during activity and may predispose the dominant ankle to a greater number of ankle sprains than the nondominant ankle.
Cardiorespiratory Responses During Underwater and Land Treadmill Exercise in College Athletes
Authors: Brubaker Peter , Ozemek Cemal , Gonzalez Alimer , Wiley Stephen , Collins Gregory
Published: August 2016

Context:

Underwater treadmill (UTM) exercise is being used with increased frequency for rehabilitation of injured athletes, yet there has been little research conducted on this modality.

Objective:

To determine the cardiorespiratory responses of UTM vs land treadmill (LTM) exercise, particularly with respect to the relationship between heart rate (HR) and oxygen consumption (VO2).

Design and Setting:

This quantitative original research took place in sports medicine and athletic training facilities at Wake Forest University.

Participants:

11 Wake Forest University student athletes (20.8 ± 0.6 y, 6 women and 5 men).

Intervention:

All participants completed the UTM and LTM exercise-testing protocols in random order. After 5 min of standing rest, both UTM and LTM protocols had 4 stages of increasing belt speed (2.3, 4.9, 7.3, and 9.6 km/h) followed by 3 exercise stages at 9.6 km/h with increasing water-jet resistance (30%, 40%, and 50% of jet capacity) or inclines (1%, 2%, and 4% grade).

Main Outcome Measures:

A Cosmed K4b2 device with Polar monitor was used to collect HR, ventilation (Ve), tidal volume (TV), breathing frequency (Bf), and VO2 every minute. Ratings of perceived exertion (RPE) were also obtained each minute.

Results:

There was no significant difference between UTM and LTM for VO2 at rest or during any stage of exercise except stage 3. Furthermore, there were no significant differences between UTM and LTM for HR, Ve, Bf, and RPE on any exercise stage. Linear regression of HR vs VO2, across all stages of exercise, indicates a similar relationship in these variables during UTM (r = .94, y = .269x − 10.86) and LTM (r = .95, y = .291x − 12.98).

Conclusions:

These data indicate that UTM and LTM exercise elicits similar cardiorespiratory responses and that HR can be used to guide appropriate exercise intensity for college athletes during UTM.
Associations Between Single-Leg Postural Control and Drop-Landing Mechanics in Healthy Women
Authors: Durall Christopher J. , Kernozek Thomas W. , Kersten Melissa , Nitz Maria , Setz Jonathan , Beck Sara
Published: August 2016

Context:

Impaired postural control in single-limb stance and aberrant drop-landing mechanics have been implicated separately as risk factors for noncontact anterior cruciate ligament (ACL) injury, but associations between these variables has not been reported.

Objective:

To determine whether there are associations between single-limb postural control and drop-landing mechanics.

Setting:

University motion-analysis laboratory.

Design:

Single-leg-landing kinematic and kinetic data were collected after participants dropped from a hang bar. Postural-control variables COP excursion and velocity were assessed during single-leg barefoot standing on a force platform.

Participants:

A convenience sample of 24 healthy women.

Main Outcome Measures:

Pearson product–moment correlation coefficients.

Results:

Strong associations were measured between maximal knee-abduction moment and COP excursion (r = .529, P = .003) and average COP velocity (r = .529, P = .003). Strong inverse associations were measured between minimum hip-flexion angle and COP excursion (r = −.521, P = .003) and average COP velocity (r = −.519, P = .003).

Conclusions:

Participants with decreased postural control had higher knee-abduction moments and a more extended hip on landing, which have been implicated separately as risk factors for ACL injury. A longitudinal prospective analysis is needed to determine whether force-platform postural-control measures can identify athletes at risk for ACL injury.
Knee-Extension Exercise’s Lack of Immediate Effect on Maximal Voluntary Quadriceps Torque and Activation in Individuals With Anterior Knee Pain
Authors: Park Jihong , Grindstaff Terry L. , Hart Joe M. , Hertel Jay N. , Ingersoll Christopher D.
Published: August 2016

Context:

Weight-bearing (WB) and non-weight-bearing (NWB) exercises are commonly used in rehabilitation programs for patients with anterior knee pain (AKP).

Objective:

To determine the immediate effects of isolated WB or NWB knee-extension exercises on quadriceps torque output and activation in individuals with AKP.

Design:

A single-blind randomized controlled trial.

Setting:

Laboratory.

Participants:

30 subjects with self-reported AKP.

Interventions:

Subjects performed a maximal voluntary isometric contraction (MVIC) of the quadriceps (knee at 90°). Maximal voluntary quadriceps activation was quantified using the central activation ratio (CAR): CAR = MVIC/(MVIC + superimposed burst torque). After baseline testing, subjects were randomized to 1 of 3 intervention groups: WB knee extension, NWB knee extension, or control. WB knee-extension exercise was performed as a sling-based exercise, and NWB knee-extension exercise was performed on the Biodex dynamometer. Exercises were performed in 3 sets of 5 repetitions at approximately 55% MVIC. Measurements were obtained at 4 times: baseline and immediately and 15 and 30 min postexercise.

Main Outcome Measures:

Quadriceps torque output (MVIC: N·m/Kg) and quadriceps activation (CAR).

Results:

No significant differences in the maximal voluntary quadriceps torque output (F2,27 = 0.592, P = .56) or activation (F2,27 = 0.069, P = .93) were observed among the 3 treatment groups.

Conclusions:

WB and NWB knee-extension exercises did not acutely change quadriceps torque output or activation. It may be necessary to perform exercises over a number of sessions and incorporate other disinhibitory interventions (eg, cryotherapy) to observe acute changes in quadriceps torque and activation.
Duration of Electrically Induced Muscle Cramp Increased by Increasing Stimulation Frequency
Authors: Miller Kevin C. , Knight Kenneth L. , Wilding Steven R. , Stone Marcus B.
Published: August 2016

Context:

Electrically induced muscle cramps (EIMC) do not last long enough to study many cramp treatments. Increasing stimulation frequency lengthens cramp duration; it is unknown which frequency elicits the longest EIMC.

Objective:

To determine which stimulation frequency elicits the longest EIMC and whether cramp duration and stimulation frequency are correlated.

Design:

Randomized, crossover.

Setting:

Laboratory.

Participants:

20 participants (12 male, 8 female; age 20.7 ± 0.6 y; height 174.9 ± 1.9 cm; mass 76.6 ± 2.2 kg) with a self-reported history of muscle cramps in their lower extremities within the 6 mo before the study.

Interventions:

The dominant leg’s tibial nerve was percutaneously stimulated with 2-s-duration electrical stimuli trains starting at a frequency of 4 Hz. After 1 min of rest, stimulation frequency increased in 2-Hz increments until a cramp occurred in the flexor hallucis brevis. The stimulation frequency at which a cramp occurred was termed cramp threshold frequency (TF). Cramp duration was determined using strict clinical criteria (loss of hallux rigidity and return of hallux neutral). On the next 4 consecutive days, participants were stimulated at 5, 10, 15, or 20 Hz above TF, and cramp duration was reassessed.

Main Outcome Measures:

Cramp TF and duration.

Results:

Cramp TF was 16.9 ± 5.1 Hz. Cramp duration was longer at 15 and 20 Hz above TF (77.9 ± 37.6 s and 69.5 ± 36.9 s, respectively) than at TF (40.8 ± 34.0 s; P < .05). Cramp duration and TF were highly correlated (r = .90). Conclusions: Stimulating at 15 and 20 Hz above cramp TF produces the longest-lasting EIMC.
The Value of Balance-Assessment Measurements in Identifying and Monitoring Acute Postural Instability Among Concussed Athletes
Authors: Cripps Andrea , Livingston Scott C.
Published: August 2016

Clinical Scenario:

Sport-related concussions are a significant health issue due to the high incidence of concussions sustained each sports season. Current approaches to the evaluation of acutely concussed athletes include the use of balance assessments to identify and monitor underlying postural instability arising from concussion. Balance assessment has been recommended as a primary measurement tool for monitoring recovery and for making return-to-play decisions. Balance impairments have been shown to occur in the initial postconcussion period (ie, 1–10 d). Numerous clinical and laboratory measures have been used in the assessment of balance immediately after concussion, and clinicians are faced with deciding which measures to use.

Focused Clinical Question:

How do clinical or field-based balance-assessment tools compare to laboratory-based balance measures in identifying deficits in postural stability among acutely concussed athletes?
Effect of Eccentric Strengthening After Anterior Cruciate Ligament Reconstruction on Quadriceps Strength
Authors: Lepley Lindsey K. , Palmieri-Smith Riann M.
Published: August 2016

Clinical Scenario:

Interventions aimed at safely overloading the quadriceps muscle after anterior cruciate ligament (ACL) reconstruction are essential to reducing quadriceps muscle weakness that often persists long after the rehabilitation period. Despite the best efforts of clinicians and researchers to improve ACL rehabilitation techniques, a universally effective intervention to restore preinjury quadriceps strength has yet to be identified. A muscle’s force-producing capacity is most optimal when an external force exceeds that of the muscle while the muscle lengthens. Hence, the potential to improve muscle strength by overloading the tissue is greater with eccentric strengthening than with concentric strengthening. Traditionally, the application of early postoperative high-intensity eccentric resistance training to the ACL-reconstructed limb has been contraindicated, as there is potential for injury to the ACL graft, articular cartilage, or surrounding soft-tissue structures. However, recent evidence suggests that the application of early, progressive, high-force eccentric resistance exercises to the involved limb can be used to safely increase muscle volume and strength in ACL-reconstructed individuals. As a result, eccentric strengthening may be another attractive alternative to traditional concentric strengthening to improve quadriceps strength after ACL reconstruction.

Focused Clinical Question:

In patients who have undergone ACL reconstruction, is there evidence to suggest that eccentric exercise positively affects postoperative quadriceps strength?
The Effects of Early Aggressive Rehabilitation on Outcomes After Anterior Cruciate Ligament Reconstruction Using Autologous Hamstring Tendon: A Randomized Clinical Trial
Authors: Christensen Jesse C. , Goldfine Laura R. , West Hugh S.
Published: August 2016

Study Design:

Prospective randomized clinical trial.

Methods and Measures:

Thirty-six patients who had a primary anterior cruciate ligament reconstruction (ACL-R) with a semitendinosus-gracilis (STG) autograft from a single orthopedic surgeon were prospectively randomized into 2 groups. Nineteen patients were randomized to the aggressive group (53% male, mean age 30.1 + 10.5 y) and 17 to the nonaggressive group (88% male, mean age 33.1 + 10.9 y). Impairment measures of anteroposterior (A-P) knee laxity, range of motion (ROM), and peak isometric force (PIF) values were obtained 12 wk postoperatively. Subjective response to the International Knee Documentation Committee knee form (IKDC) was collected 1, 12, and 24 wk postoperatively. One-way ANOVA was used to analyze differences between groups at 12 wk for A-P knee laxity, ROM, and PIF. Differences between the groups for the IKDC scores were determined using 1-way ANOVA with repeated measures 1, 12, and 24 wk postoperatively. Bonferroni adjustment was used for multiple comparisons.

Results:

There were no differences between the groups for the baseline characteristics (P > .05). There was no difference found between the groups in respect to A-P knee laxity, ROM, or PIF at 12 wk (P > .05). Further analysis also showed no significant differences in the IKDC scores between groups at 12 or 24 wk (P > .05).

Conclusions:

No differences were found between early aggressive and nonaggressive rehabilitation after an isolated ACL-R using STG autografts for the primary outcomes of A-P knee laxity and subjective IKDC score. In addition, no differences were observed for secondary outcomes between groups for differences in ROM and PIF values.
Negative Effects on Postural Control After Anterior Cruciate Ligament Reconstruction as Measured by the Balance Error Scoring System
Authors: Smith Mason D. , Bell David R.
Published: August 2016

Context:

Anterior cruciate ligament (ACL) reconstruction is the standard of care for individuals with ACL rupture. Balance deficits have been observed in patients with ACL reconstruction (ACLR) using advanced posturography, which is the current gold standard. It is unclear if postural-control deficits exist when assessed by the Balance Error Scoring System (BESS), which is a clinical assessment of balance.

Objective:

The purpose of this study is to determine if postural-control deficits are present in individuals with ACLR as measured by the BESS.

Participants:

Thirty participants were included in this study. Fifteen had a history of unilateral ACLR and were compared with 15 matched controls.

Interventions:

The BESS consists of 3 stances (double-limb, single-limb, and tandem) on 2 surfaces (firm and foam). Participants begin in each stance with hands on their hips and eyes closed while trying to stand as still as possible for 20 s.

Main Outcome Measures:

Each participant performed 3 trials of each stance (18 total), and errors were assessed during each trial and summed to create a total score.

Results:

We observed a significant group × stance interaction (P = .004) and a significant main effect for stance (P < .001). Post hoc analysis revealed that the ACLR group had worse balance on the single-leg foam stance than did controls. Finally, the reconstructed group had more errors when total BESS score was examined (P = .02).

Conclusions:

Balance deficits exist in individuals with ACLR as measured by the BESS. Total BESS score was different between groups. The only condition that differed between groups was the single-leg stance on the unstable foam surface.
Relationship Between Gluteal Muscle Strength, Corticospinal Excitability, and Jump-Landing Biomechanics in Healthy Women
Authors: Lepley Adam S. , Strouse Allison M. , Ericksen Hayley M. , Pfile Kate R. , Gribble Phillip A. , Pietrosimone Brian G.
Published: August 2016

Context:

Components of gluteal neuromuscular function, such as strength and corticospinal excitability, could potentially influence alterations in lower extremity biomechanics during jump landing.

Objective:

To determine the relationship between gluteal muscle strength, gluteal corticospinal excitability, and jump-landing biomechanics in healthy women.

Setting:

University laboratory.

Design:

Descriptive laboratory study.

Participants:

37 healthy women (21.08 ± 2.15 y, 164.8 ± 5.9 cm, 65.4 ± 12.0 kg).

Interventions:

Bilateral gluteal strength was assessed through maximal voluntary isometric contractions (MVIC) using an isokinetic dynamometer. Strength was tested in the open chain in prone and side-lying positions for the gluteus maximus and gluteus medius muscles, respectively. Transcranial magnetic stimulation was used to elicit measures of corticospinal excitability. Participants then performed 3 trials of jump landing from a 30-cm box to a distance of 50% of their height, with an immediate rebound to a maximal vertical jump. Each jump-landing trial was video recorded (2-D) and later scored for errors.

Main Outcome Measures:

MVICs normalized to body mass were used to assess strength in the gluteal muscles of the dominant and nondominant limbs. Corticospinal excitability was assessed by means of active motor threshold (AMT) and motor-evoked potentials (MEP) elicited at 120% of AMT. The Landing Error Scoring System (LESS) was used to evaluate jump-landing biomechanics.

Results:

A moderate, positive correlation was found between dominant gluteus maximus MEP and LESS scores (r = .562, P = .029). No other significant correlations were observed for MVIC, AMT, or MEP for the gluteus maximus and gluteus medius, regardless of limb.

Conclusions:

The findings suggest a moderate relationship between dominant gluteus maximus corticospinal excitability and a clinical measure of jump-landing biomechanics. Further research is required to substantiate the findings and expand our understanding of the central nervous system’s role in athletic movement.