Impact of hindlimb length variation on jumping dynamics in the Longshanks mouse.

Distantly related mammals (e.g. jerboa, tarsiers, kangaroos) have convergently evolved elongated hindlimbs relative to body size. Limb elongation is hypothesized to make these species more effective jumpers by increasing their kinetic energy output (through greater forces or acceleration distances), thereby increasing take-off velocity and jump distance. This hypothesis, however, has rarely been tested at the population level, where natural selection operates. We examined the relationship between limb length, muscular traits and dynamics using Longshanks mice, which were selectively bred over 22 generations for longer tibiae. Longshanks mice have approximately 15% longer tibiae and 10% longer femora compared with random-bred Control mice from the same genetic background. We collected in vivo measures of locomotor kinematics and force production, in combination with behavioral data and muscle morphology, to examine how changes in bone and muscle structure observed in Longshanks mice affect their hindlimb dynamics during jumping and clambering. Longshanks mice achieved higher mean and maximum lunge-jump heights than Control mice. When jumping to a standardized height (14 cm), Longshanks mice had lower maximum ground reaction forces, prolonged contact times and greater impulses, without significant differences in average force, power or whole-body velocity. While Longshanks mice have longer plantarflexor muscle bodies and tendons than Control mice, there were no consistent differences in muscular cross-sectional area or overall muscle volume; improved lunge-jumping performance in Longshanks mice is not accomplished by simply possessing larger muscles. Independent of other morphological or behavioral changes, our results point to the benefit of longer hindlimbs for performing dynamic locomotion.

Inertial Sensor-Based Quantification of Movement Symmetry in Trotting Warmblood Show-Jumping Horses after "Limb-by-Limb" Re-Shoeing of Forelimbs with Rolled Rocker Shoes.

Hoof care providers are pivotal for implementing biomechanical optimizations of the musculoskeletal system in the horse. Regular visits allow for the collection of longitudinal, quantitative information ("normal ranges"). Changes in movement symmetry, e.g., after shoeing, are indicative of alterations in weight-bearing and push-off force production. Ten Warmblood show jumping horses (7-13 years; 7 geldings, 3 mares) underwent forelimb re-shoeing with rolled rocker shoes, one limb at a time ("limb-by-limb"). Movement symmetry was measured with inertial sensors attached to the head, withers, and pelvis during straight-line trot and lunging. Normalized differences pre/post re-shoeing were compared to published test-retest repeatability values. Mixed-model analysis with random factors horse and limb within horse and fixed factors surface and exercise direction evaluated movement symmetry changes (p < 0.05, Bonferroni correction). Withers movement indicated increased forelimb push-off with the re-shod limb on the inside of the circle and reduced weight-bearing with the re-shod limb and the ipsilateral hind limb on hard ground compared to soft ground. Movement symmetry measurements indicate that a rolled rocker shoe allows for increased push-off on soft ground in trot in a circle. Similar studies should study different types of shoes for improved practically relevant knowledge about shoeing mechanics, working towards evidence-based preventative shoeing.

Neuromuscular fatigue and muscle damage following a simulated singles badminton match.

PURPOSE: To understand muscle damage in badminton, changes in neuromuscular function were investigated after simulated badminton singles matches performed by ten state-level male players. METHODS: Each participant played eight matches and measurements were taken before, immediately after, and 1 and 24 h after each match. Maximal voluntary isometric contraction (MVC) torque of the knee extensors and flexors, voluntary activation (VA) during MVC and torques generated by doublet (TDoublet), 20 (T20) and 80 Hz (T80) electrical stimulations of the knee extensors were measured from the dominant leg (the racket-hold arm side). Muscle soreness was assessed by a 100-mm visual analogue scale from both legs. The number of lunges performed by each participant in each match was analysed by videos, and its relations to other measures were examined. RESULTS: Pre-match knee extensor and flexor MVC torques were 278.4 ± 50.8 Nm and 143.0 ± 36.2 Nm, respectively. Knee extensor MVC torque of the dominant leg decreased immediately (12.0 ± 2.9%) and 1 h post-match (16.0 ± 3.2%), but returned to baseline at 24 h post-match. VA (11.4 ± 2.9%), TDoublet (13.1 ± 6.0%), T20 (31.1 ± 12.3%) and T80 (25.5 ± 7.9%) decreased (p < 0.01) immediately post-match but recovered by 24 h post-match. A significant correlation (r = - 0.64, p < 0.01) was observed between the total number of lunges performed in a match (160-240 times) and the magnitude of decrease in MVC torque (6.4-14.7%). Muscle soreness developed more (p < 0.05) for the dominant (51.5 ± 11.6 mm) than the non-dominant leg (18.8 ± 8.6 mm). CONCLUSION: Muscle damage induced by singles badminton matches was minimal, but the more the lunges are performed, the greater the neuromuscular fatigue.

Medial stability and lateral flexibility of the collateral ligaments during mid-range flexion in medial-pivot total knee arthroplasty patients demonstrates favorable postoperative outcomes.

PURPOSE: The objectives of the present study were to investigate the length change in different bundles of the superficial medial collateral ligament (sMCL) and lateral collateral ligament (LCL) during lunge, and to evaluate their association with Knee Society Score (KSS) following medial-pivot total knee arthroplasty (MP-TKA). METHODS: Patients with unilateral MP-TKA knees performed a bilateral single-leg lunge under dual fluoroscopy surveillance to determine the in-vivo six degrees-of-freedom knee kinematics. The contralateral non-operated knees were used as the control group. The attachment sites of the sMCL and LCL were marked to calculate the 3D wrapping length. The sMCL and LCL were divided into anterior, intermediate, and posterior portions (aMCL, iMCL, pMCL, aLCL, iLCL, pLCL). Correlations between lengths/elongation rate of ligament bundles from full extension to 100° flexion and the KSS were examined. RESULTS: The sMCL and LCL demonstrated relative stability in length at low flexion, but sMCL length decreased whereas LCL increased with further flexion on operated knees. The sMCL length increased at low flexion and remained stable with further flexion, while the LCL length decreased with flexion on the contralateral non-operated knees. The lengths of aMCL, iMCL, and pMCL showed moderate (0.5 < r < 0.7, p < 0.05) negative correlations with the KSS, and the lengths of aLCL, iLCL, and pLCL were positively correlated with the KSS at mid flexion on operated knees (p < 0.05). The elongation rates of aLCL, iLCL, and pLCL were negatively correlated with the KSS at high flexion on operated knees (p < 0.05). However, no significant correlations between the length of different bundles of sMCL or LCL with KSS were found on contralateral non-operated knees. CONCLUSIONS: The elongation pattern of sMCL/LCL on MP-TKA knees showed differences with contralateral non-operated knees. The sMCL is tense at low to middle flexion and relaxed at high flexion, while LCL is relaxed at low to middle flexion and tense at high flexion following MP-TKA. Medial stability and proper lateral flexibility during mid flexion were associated with favorable postoperative outcomes in MP-TKA patients. In contrast, lateral relaxation at deep flexion should be avoided when applying soft-tissue balancing in MP-TKA. LEVEL OF EVIDENCE: Level III.

Circle Diameter Impacts Stride Frequency and Forelimb Stance Duration at Various Gaits in Horses.

The effects of gait and diameter have been studied independently, but rarely together in equine circular exercise studies. This study aimed to determine the impact of diameter (10-m or 15-m) at various gaits (walk, trot, and canter) on stride frequency or forelimb stance duration. Nine mature horses were outfitted with Tekscan™ Hoof Sensors on their forelimbs during circular and straight-line exercise at various gaits on a clay and sand arena surface. Statistical analysis was performed in SAS 9.4 with fixed effects of exercise type, recording, leg, and breed (PROC GLIMMIX, p < 0.05 significance). At walk (p < 0.0001) and trot (p < 0.001), stride frequency was lower during circular exercise. Stride frequency was similar between forelimbs at all gaits. At walk (p < 0.001) and canter (p = 0.01), stance duration was greatest during 10-m circle exercise. At walk (p = 0.0007), trot (p < 0.001), and canter (p < 0.0001), the inside forelimb had longer stance duration than the outside forelimb. Differences between forelimb stance durations may support asymmetrical travel while horses exercise on a circle at the walk, trot, and canter. These results demonstrate diameter and gait are important factors when evaluating forelimb kinematics during circular exercise.

Weight-Bearing Exercises on Slideboard Increase Quadriceps and Hamstring Activation Levels and Improve Hip- and Knee-Flexion Angles in Physically Active Individuals.

CONTEXT: Slideboards are commonly used in exercise programs, but there is limited information about how they affect muscle activities during exercise. We aim to compare the activation levels of quadriceps and hamstring muscles and hip- and knee-flexion angles during lunge and single-leg squat exercises between normal ground and slideboard in physically active individuals. DESIGN: Cross-sectional study. METHODS: Thirty healthy individuals (age: 23.83 [2.84] y, body mass index: 21.75 [1.72] kg/m2) were included in the study. Surface electromyography was used to measure vastus medialis, vastus lateralis, biceps femoris, and semitendinosus activation levels during reaching and returning phases of the forward, lateral, and back lunges and squats that were performed on the normal ground and slideboard. Exercises were performed at a slow pace (60 beats/min). Hip- and knee-flexion angles during the exercises were evaluated by using 2-dimensional motion analysis. Repeated measures of analysis of variance were used for statistical analysis. RESULTS: Vastus medialis and vastus lateralis activation levels were greater during reaching and returning phases of the exercises on slideboard compared with normal ground (P < .05). However, semitendinosus and biceps femoris activity were greater only during the returning phase of the forward lunge (P < .001) and the returning phase of the back squat (P = .002, P = .009, respectively). Hip-to-knee flexion ratios were closer to 1 when the forward lunge (P < .001), back lunge (P = .004), and forward squat (P = .001) exercises were performed on a slideboard. CONCLUSION: In exercise programs that target the quadriceps and hamstring muscles, slideboards can be effectively used in exercise progressions as they can increase muscle activity. Moreover, squat and lunge exercises on slideboard with a slow pace may also be helpful for improving the balance between hip- and knee-flexion angles.

Intrarater and Interrater Reliability and Agreement of a Method to Quantify Lower-Extremity Kinematics Using Remote Data Collection.

CONTEXT: To assess the reliability of a remote 2D markerless motion tracking method (Kinovea) to quantify knee and hip angles during dynamic tasks. METHODS: Fourteen healthy adults performed body weight squats and lateral lunges while video recording themselves at home. Knee and hip angles were quantified in the sagittal plane for the squats and in the frontal plane for the lateral lunges. Two students each performed the video analysis procedure twice, 2 weeks apart. Intraclass correlation coefficients were used to calculate the intrarater and interrater reliability for angles at maximum depth. The intrarater and interrater agreement over the joint angle-time signals were quantified using a validation metric; an acceptable agreement threshold was set at a validation metric of 0.803 or higher. Standard error of measurement (SEM) was also calculated. RESULTS: Reliability was good to excellent (intraclass correlation coefficients = .80-.98) for all angle comparisons at maximum depth. The agreement over the entire joint angle-time signal was acceptable for all squat variables except for the interrater hip angle comparison (validation metric = 0.797). None of the lateral lunge variables met the threshold of acceptable agreement. The mean SEM across participants for all joint angle-time signal and for maximum depth was acceptable (<5°) for all measurements (SEM = 1.2°-4.9°). CONCLUSIONS: Overall, the reliability, agreement, and SEM quantified in this study support the integration of remote methods to quantify lower-extremity kinematics into research and clinical practice.

Asymmetrical tibial polyethylene geometry-cruciate retaining total knee arthroplasty does not fully restore in-vivo articular contact kinematics during strenuous activities.

PURPOSE: A new CR TKA design with concave medial and convex lateral tibial polyethylene bearing components was introduced recently to improve functional outcomes. This study aimed to investigate in-vivo articular contact kinematics in unilateral asymmetrical tibial polyethylene geometry CR TKA patients during strenuous knee flexion activities. METHODS: Fifteen unilateral CR TKA patients (68.4 ± 5.8 years; 6 male/9 female) were evaluated for both knees during sit-to-stand, single-leg deep lunges and step-ups using validated combined computer tomography and dual fluoroscopic imaging system. Medial and lateral condylar contact positions were quantified during weight-bearing flexion activities. The Wilcoxon signed-rank test was performed to determine if there is a significant difference in articular contact kinematics during strenuous flexion activities between CR TKA and the non-operated knees. RESULTS: Contact excursions of the lateral condyle in CR TKAs were significantly more anteriorly located than the contralateral non-operated knee during sit-to-stand (3.7 ± 4.8 mm vs - 7.8 ± 4.3 mm) and step-ups (- 1.5 ± 3.2 mm vs - 6.3 ± 5.8 mm). Contact excursions of the lateral condyle in CR TKAs were significantly less laterally located than the contralateral non-operated knee during sit-to-stand (21.4 ± 2.8 mm vs 24.5 ± 4.7 mm) and single-leg deep lunges (22.6 ± 4.4 mm vs 26.2 ± 5.7 mm, p < 0.05). Lateral condyle posterior rollback was not fully restored in CR TKA patients during sit-to-stand (9.8 ± 6.7 mm vs 12.9 ± 8.3 mm) and step-ups (8.1 ± 4.8 mm vs 12.2 ± 6.4 mm). Lateral pivoting patterns were observed in 80%, 73% and 69% of patients during sit-to-stand, step-ups and single-leg deep lunges respectively. CONCLUSION: Although lateral femoral rollback and lateral pivoting patterns were observed during strenuous functional daily activities, asymmetric contact kinematics still persisted in unilateral CR TKA patients. This suggests the specific investigated contemporary asymmetrical tibial polyethylene geometry CR TKA design evaluated in this study does not fully replicate healthy knee contact kinematics during strenuous functional daily activities. LEVEL OF EVIDENCE: III.

Differences of quadriceps activity during inline lunge by using FMS assessment.

[Purpose] This study assessed the exercise capacity of healthy adults while performing the inline lunge exercise by using Functional Movement Screen (FMS). Compared the difference in muscle activity of the quadriceps according to the exercise capacity. [Participants and Methods] Thirty two healthy participants (12 males, 20 females) participated in this study. The surface electromyography (sEMG) was used to measure the electrical activities for the vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL) of quadriceps. [Results] Both groups had significant difference when sitting up and getting up during the inline lunge. In scores 3 group, vastus medialis showed higher muscle activity than vastus lateralis. On contrary, in scores 2 group, vastus lateralis had higher muscle activity than vastus medialis. [Conclusion] Therefore, this study suggests that inline lunge can help to strengthen the quadriceps effectively by showing the difference of quadriceps activity according to exercise capacity.

Body size in relation to cubicle dimensions affects lying behavior and joint lesions in dairy cows.

Adequate cubicle dimensions are important for dairy cows to allow for species-appropriate lying behavior. Even though cow body size has increased in the last 2 decades, the cubicle dimensions of housing systems built many years ago have not been adjusted on most farms. Therefore, cows may be impaired in their lying behaviors, and thus the present study aimed to determine the influence of the ratio of body size to cubicle dimension on lying behavior and joint lesions. We investigated the lying behavior of 144 cows with withers heights of 140 to 163 cm on 8 Swiss dairy farms. Among the farms, the cubicle bed length varied from 187 to 200 cm and lunge space length varied from 47 to 202 cm. Specific behaviors of lying down and standing up movements, as well as lying positions, were observed on 3 d per farm. As outcome variables, the occurrences of these behaviors were calculated as proportions in relation to the respective total number of observations per cow. In addition, the presence of joint lesions was scored once. Data of the individual cows were analyzed in relation to the given cubicle dimensions on the farms by mixed-effects models. The bed length ratio [bed length (cm) on the farm/withers height (cm) of the observed cow] and the lunge space ratio [lunge space length (cm) on the farm/withers height (cm) of the observed cow] were used as explanatory variables. An increase in the bed length ratio was associated with decreased proportions of lying down movements with (1) repeated head pendulum movements, (2) repeated stepping with front legs, and (3) hitting against cubicle elements; decreased proportions of standing up movements with (1) shifting backward, (2) hesitant head lunge movements, and (3) hitting against cubicle elements; and an increased proportion of lying positions without physical contact with cubicle elements. An increase in the lunge space ratio was associated with a decreased proportion of standing up movements with sideways directed head lunge movements. Furthermore, an increase in the bed length ratio decreased the proportion of cows with tarsal joint lesions. To summarize, the lying behavior of large-framed cows was clearly modified given the cubicle dimensions in use on the study farms. In view of the consistency of the obtained results, we recommend adjusting the dimensions of cubicles so that they are suitable for cows whose body size meets the breeding goals of the farm.

Multi-radius posterior-stabilized mobile-bearing total knee arthroplasty partially produces in-vivo medial pivot during activity of daily living and high demanding motor task.

PURPOSE: The purpose of the present study was to assess the kinematical behavior of a multi-radius posterior-stabilized (PS) mobile-bearing (MB) total knee arthroplasty (TKA) during an activity of daily living (Sit-To-Stand-STS) and a high demanding motor task (Deep-Knee-Lunge-DKL) using model-based dynamic RSA. We hypothesized the achievement of medial pivoting movement in both motor tasks due to the congruent geometry of the inlay with the femoral component, which should allow good stability of the medial compartment, and to the high magnitude of rotations guaranteed by the MB on the tibial side. METHODS: Twenty-two randomly selected patients were recruited and prospectively evaluated. The PS MB cemented TKA was implanted with the standard technique (medial parapatellar approach, adjusted mechanical alignment). At minimum 9-month follow-up, patients were examined with model based Dynamic RSA developed in our Institute (BI-STAND DRX 2) during the execution of two motor tasks: STS and DKL. The motion parameters were evaluated using the Grood and Suntay decomposition and the low-point kinematics methods. RESULTS: In the extension phase of DKL femur performed a greater antero posterior translation of 3.8 mm compared to STS between 0° and 20° of knee flexion (p < 0.05). Low-point analysis showed a medial pivoting movement in both motor tasks: in 62% of patients during STS and 48% during DKL. Varus-valgus rotations were lower than 1° during all the range-of-motion in both motor tasks without differences. CONCLUSIONS: Medial pivot was partially produced by this multi-radius PS MB TKA with some differences during activity of daily living (STS) and high demanding motor task (DKL). LEVEL OF EVIDENCE: IV.

Gastrocnemius tightness: A population based observational study.

BACKGROUND: Gastrocnemius tightness is believed to be associated with multiple musculoskeletal pathologies such as back pain, plantar fasciitis and metatarsalgia. Although surgical treatment of gastrocnemius tightness is gaining popularity the objective definition of a gastrocnemius contracture has not been determined. The aim of our study was therefore to quantify gastrocnemius tightness in a normal population. METHODS: Adult participants with no obvious foot and ankle pathology were recruited. Gastrocnemius tightness was quantified using a weightbearing lunge test. Maximal ankle-foot dorsiflexion was measured on participants with the knee in full extension and flexed to 20° using a digital inclinometer. The ankle-foot dorsiflexion index or ADI (difference in ankle dorsiflexion with the knee extended and flexed) was calculated. The ADI values were plotted on a histogram to identify the distribution of values and were compared according to participant demographics. RESULTS: 800 limbs from 400 participants were examined. There was a wide distribution of absolute values of maximal ankle-foot dorsiflexion ranging from 8 to 52°. The ADI ranged from 0 to19° and approximated to a normal distribution. The mean ADI was 6.04±3.49° and was positively correlated with age (r=0.132, P<0.001) and negatively correlated with physical activity (r=-0.88, P=0.015). CONCLUSION(S): Our study is the first to quantify gastrocnemius tightness in a large healthy adult population with differences observed by age and physical activity. We have defined an easy and reproducible weightbearing test that can be used in both research and clinical settings. The majority of the population have some degree of gastrocnemius tightness and values of ADI greater than 13° (>2 SD of the mean), as measured by the lunge test, may be considered abnormal.

Weight bearing versus non-weight bearing ankle dorsiflexion measurement in people with diabetes: a cross sectional study.

BACKGROUND: Accurate measurement of ankle dorsiflexion is important in both research and clinical practice as restricted motion has been associated with many foot pathologies and increased risk of ulcer in people with diabetes. This study aimed to determine the level of association between non-weight bearing versus weight bearing ankle dorsiflexion in adults with and without diabetes, and to evaluate the reliability of the measurement tools. METHODS: One hundred and thirty-six adults with diabetes and 30 adults without diabetes underwent ankle dorsiflexion measurement non-weight bearing, using a modified Lidcombe template, and weight bearing, using a Lunge test. Pearson product-moment correlation coefficients, intraclass correlation coefficients (ICCs) with 95% confidence intervals, standard error of measurement and minimal detectable change were determined. RESULTS: There was a moderate correlation (r = 0.62-0.67) between weight and non-weight bearing tests in the non-diabetes group, and a negligible correlation in the diabetes group(r = 0.004-0.007). Intratester reliability was excellent in both groups for the modified Lidcombe template (ICC = 0.89-0.94) and a Lunge test (ICC = 0.83-0.89). Intertester reliability was also excellent in both groups for the Lidcombe template (ICC = 0.91) and a Lunge test (ICC = 0.88-0.93). CONCLUSIONS: We found the modified Lidcombe template and a Lunge test to be reliable tests to measure non-weight bearing and weight bearing ankle dorsiflexion in adults with and without diabetes. While both methods are reliable, further definition of weight bearing ankle dorsiflexion normative ranges may be more relevant for clinical practice.

[The frequency of abnormal ultrasonographic findings in the lungs of 129 calves with bronchopneumonia]. / Häufigkeit abnormer Ultraschallbefunde an der Lunge von 129 Kälbern mit Bronchopneumonie.

INTRODUCTION: The goal of this study was to analyse the frequency of ultrasonographic findings in 129 calves with bronchopneumonia and to determine how often multiple abnormalities occur in individual calves. The frequency of abnormal ultrasonographic findings ranged from 4 to 88%. Comet-tail artifacts were the most common finding (88%) followed in decreasing order by scattered echogenic foci (69%), air bronchograms (44%), superficial alveolograms (29%), pleural effusion (26%), hepatisation (23%), pleural lesions (18%), fluid bronchograms (14%), lung abscesses (6%) and fibrin deposits or fibrin strands (4%). Thoracic ultrasonography yielded a mean of 3.3 ± 1.55 abnormal findings (range, 1-6) per calf. Ultrasonography of the lungs in calves with bronchopneumonia is a useful adjunct to clinical examination and allows the determination of the type and severity of lesions.

INTRODUCTION: Dans la présente étude, la fréquence des constatations échographiques anormales recueillies sur 129 veaux souffrant de bronchopneumonie a été évaluée de manière rétrospective. Il a également été étudié combien de fois un veau présentait simultanément plusieurs découvertes. La fréquence des échographies anormales variait entre 4 et 88%. Des artefacts en queue de comète représentaient, avec 88%, les découvertes anormales les plus courantes. Ils étaient, par ordre décroissant, suivi par des réflexions de l'air (69%), des bronchogrammes aériens (44%), des alvéologrammes superficiels (29%), un épanchement pleural (26%), une hépatisation (23%), des altérations pleurales (18%), des bronchogrammes liquidiens (14%), des abcès pulmonaires (6%) et de la fibrine ou des ponts de fibrine (4%). En moyenne 3,3 ± 1,55 résultats d'échographie anormaux ont été déterminés par veau. L'examen échographique des poumons est, chez les veaux souffrant d'une bronchopneumonie, un complément précieux à l'examen clinique. Il permet de représenter la nature et la gravité des changements de bronchopneumonie et de les objectiver.

A biomechanical investigation of right-forward lunging step among badminton players.

This study presents the kinematics and plantar pressure characteristics of eight elite national-level badminton athletes and eight recreational college-level badminton players while performing a right-forward lunge movement in a laboratory-simulated badminton court. The hypothesis was that recreational players would be significantly different from elite players in kinematics and plantar pressure measures. Vicon® motion capture and Novel® insole plantar pressure measurement were simultaneously taken to record the lower extremity kinematics and foot loading during stance. Recreational players showed significantly higher peak pressure in the lateral forefoot (P = 0.002) and force time integral in the lateral forefoot (P = 0.013) and other toes (P = 0.005). Elite athletes showed higher peak pressure in the medial forefoot (P = 0.003), hallux (P = 0.037) and force time integral in the medial forefoot (P = 0.009). The difference in landing techniques for the lunge step between elite athletes and recreational players was observed with peak ankle eversion (-38.2°±2.4° for athletes and -11.1°±3.9° for players, P = 0.015); smaller knee range of motion in the coronal and transverse planes, with differences in peak knee adduction (28.9°±6.8° for athletes and 15.7°±6.2° for players, P = 0.031); peak knee internal rotation (20.3°±1.3° for athletes and 11.8°±3.2° for players, P = 0.029) and peak hip flexion (77.3°±4.1° for athletes and 91.3°±9.3° for players, P = 0.037).

Changes in lower limb muscle activity based on angle of ankle abduction during lunge exercise.

[Purpose] This study compared the activity of the quadriceps femoris muscle according to the angle of ankle abduction during a lunge exercise. [Subjects and Methods] Fifteen male healthy volunteers participated in the study. All participants performed the lunge exercise with different angles of ankle abduction (0°, 20°, 40°, 60°). The activity of the rectus femoris (RF), vastus lateralis (VL) and vastus medialis oblique (VMO) muscles were recorded for the four angles by using a surface electromyography system. [Results] There were significant differences between the rectus femoris (RF), vastus lateralis (VL) and vastus medialis oblique (VMO) with every angle of the ankle joint. The most significantly increased muscle activity was evident in the vastus medialis oblique (VMO) when the ankle abduction was 60°. [Conclusion] These findings suggest that as the ankle abduction angle increases during the lunge exercise, the muscle activity of the quadriceps femoris muscle increases and this could be helpful in the selective muscle strengthening of the vastus medialis oblique muscle (VMO) with the ankle in the 60° abduction position.

Associations between ankle dorsiflexion range of motion and foot and ankle strength in young adults.

[Purpose] This study assessed the relationships between the ankle dorsiflexion range of motion and foot and ankle strength. [Subjects and Methods] Twenty-nine healthy (young adults) volunteers participated in this study. Each participant completed tests for ankle dorsiflexion range of motion, hallux flexor strength, and ankle plantar and dorsiflexor strength. [Results] The results showed (1) a moderate correlation between ankle dorsiflexor strength and dorsiflexion range of motion and (2) a moderate correlation between ankle dorsiflexor strength and first toe flexor muscle strength. Ankle dorsiflexor strength is the main contributor ankle dorsiflexion range of motion to and first toe flexor muscle strength. [Conclusion] Ankle dorsiflexion range of motion can play an important role in determining ankle dorsiflexor strength in young adults.

Evidence for the perceptual origin of right-sided feeding biases in cetaceans.

Foraging behaviour of many cetacean species features the side biases at the population level. The origin of these behavioural lateralisations remains generally unclear. Here we explored lateralisation in aerial display of resident orcas in different behavioural contexts. Side preferences were analysed in lunging during foraging and breaching. One event of each type of displays per individually identified orca was used for analysis. Orcas showed a population-level preference to lunge on the right side when foraging (75% of lunges). In contrast, no lateralisation was found in breaching (54% of breaches to the right, 45% to the left). The right-sided bias in foraging found in orcas is in line with evidence from other whales, both baleen and toothed, and confirms the uniformity of feeding biases among cetaceans. In contrast to breaching, lunging in orcas was associated with fish pursuit, that is, with focused attention to and sensory perception of prey stimulus. The emergence of lateralisation in lunging and the absence of significant bias in breaching suggest that feeding biases in whales are underpinned by sensory lateralisation, that is, by lateralised hemispheric processing of sensory information about the prey. Evidence from orcas may be extrapolated to other cetaceans since right-sided biases in lunging during foraging is a very widespread phenomenon and likely to have a common origin. Our findings support the hypothesis that right-sided feeding biases are determined by left-hemisphere specialisation.

Effects of ankle eversion taping using kinesiology tape in a patient with ankle inversion sprain.

[Purpose] The aim of this study was to report the effects of ankle eversion taping using kinesiology tape on ankle inversion sprain. [Subject] The subject was a 21-year-old woman with Grade 2 ankle inversion sprain. [Methods] Ankle eversion taping was applied to the sprained left ankle using kinesiology tape for 4 weeks (average, 15 h/day). [Results] Ankle instability and pain were reduced, and functional dynamic balance was improved after ankle eversion taping for 4 weeks. The Cumberland Ankle Instability Tool score and reach distances in the Y-Balance and lunge tests were increased. [Conclusion] Repeated ankle eversion taping may be an effective treatment intervention for ankle inversion sprain.

Biomechanical analysis of knee and trunk in badminton players with and without knee pain during backhand diagonal lunges.

The contribution of core neuromuscular control to the dynamic stability of badminton players with and without knee pain during backhand lunges has not been investigated. Accordingly, this study compared the kinematics of the lower extremity, the trunk movement, the muscle activation and the balance performance of knee-injured and knee-uninjured badminton players when performing backhand stroke diagonal lunges. Seventeen participants with chronic knee pain (injured group) and 17 healthy participants (control group) randomly performed two diagonal backhand lunges in the forward and backward directions, respectively. This study showed that the injured group had lower frontal and horizontal motions of the knee joint, a smaller hip-shoulder separation angle and a reduced trunk tilt angle. In addition, the injured group exhibited a greater left paraspinal muscle activity, while the control group demonstrated a greater activation of the vastus lateralis, vastus medialis and medial gastrocnemius muscle groups. Finally, the injured group showed a smaller distance between centre of mass (COM) and centre of pressure, and a lower peak COM velocity when performing the backhand backward lunge tasks. In conclusion, the injured group used reduced knee and trunk motions to complete the backhand lunge tasks. Furthermore, the paraspinal muscles contributed to the lunge performance of the individuals with knee pain, whereas the knee extensors and ankle plantar flexor played a greater role for those without knee pain.