Effects of Corrective Training on Drop Landing Ground Reaction Force Characteristics and Lower Limb Kinematics in Older Adults With Genu Valgus:A Randomized Controlled Trial

The aim of this study was to identify the effects of a corrective exercise program on landing ground reaction force characteristics and lower limb kinematics in older adults with genu valgus. A total of 26 older male adults with genu valgus were randomized into two groups. An experimental group conducted a 14-week corrective exercise program, whereas a control group did not perform any exercise. The experimental group displayed lower peak vertical, peak anterior and posterior, and peak medial ground reaction force components during the posttest compared with the pretest. The vertical loading rate, impulses, and free moment amplitudes were not statistically different between groups. In the experimental group, the peak knee abduction during the posttest was significantly smaller and the peak hip flexion angle was significantly greater than during the pretest. The authors suggest that this corrective exercise program may be a suitable intervention to improve landing ground reaction forces and lower limb kinematics in older male adults with genu valgus

Quantifying lower limb inter-joint coordination and coordination variability after four-month wearing arch support foot orthoses in children with flexible flat feet

Introduction: Flat feet in children negatively affect lower limb alignment and cause adverse health-related problems. The long-term application of foot orthoses (FOs) may have the potential to improve lower limb coordination and its variability. Aim: To evaluate the effects of long-term use of arch support FOs on inter-joint coordination and coordination variability in children with flexible flat feet. Methods: Thirty boys with flexible flat feet were randomly assigned to the experimental (EG) and control groups. The EG used medial arch support FOs during daily activities over a four-month period while the control group received a flat 2-mm-thick insole for the same time period. Lower-limb coordination and variability during the 3 sub-stance phases were quantified using a vector coding technique. Results: Frontal plane ankle-hip coordination in EG during mid-stance changed to an anti-phase pattern (156.9) in the post-test compared to an in-phase (221.1) in the pre-test of EG and posttest of CG (222.7). Frontal plane knee-hip coordination in EG during loading response (LR) changed to an anti-phase pattern (116) in the post-test compared to an in-phase (35.5) in the pre-test of EG and post-test of CG (35.3). Ankle inversion/eversion-knee internal/external rotation joint coupling angle in EG changed to an in-phase pattern (59) in the post-test compared to a proximal phase (89) in the pre-test. Coupling angle variability increased in the post-test of EG for sagittal plane ankle-hip during push-off, transverse plane ankle-hip during LR and mid-stance, and transverse plane knee-hip during LR and mid-stance compared to pre-test of EG and post-test of CG. Conclusion: The long-term use of arch support FOs proved to be effective to alter lower limb coordination and coordination variability during walking in children with flexible flat feet. This new insight into coordinative function may be useful for improving corrective exercise strategies planned for children with flat feet

Corrigendum to "Quantifying lower limb inter-joint coordination and coordination variability after four-month wearing arch support foot orthoses in children with flexible flat feet" [Human Movement Science 70 (2020) 102593]

The authors regret: The first line under section 2.4 Calculation of coordination and coordination variability should read: • ‘The following equations are based on the step by step approach devised and reported by Needham et al. (2014)’. • Cite Chang et al. (2008) in addition to Sparrow et al. (1987) for equation, 4. Chang et al. (2008) already cited in paper. • Cite Batschelet (1981) in addition to Hamill et al., (2000). Batschelet, E., 1981. Circular Statistics in Biology. Academic Press, New York. The authors would like to apologise for any inconvenience caused.</p

A Kinematic Analysis of Upper Extremity Joint when Punching by Three Different Methods in Athletes of Different Skill Levels

Objective: The aim of this study was to comare the Kinematics Analysis of attackting arm of Boxors when they perform punching using three techniques: shadow boxing, punch against punching bag and punch against guard of opponent. The influence of technical skill level was also investigated by comparing two groups: elite Boxors and Amateurs. Methods: The study was carried out on 10 elite Boxors and 10 Amateurs with healthy shoulder and elbow joint in dominant arm. Each participant was asked to perfom six shadow punching (punch to virtual opponent), six punches against punching bag and six punch against guard of opponent as hard as possible, while Kinematics variable of punching arm and forearm was recorded by using four vicon cameras at 200 HZ. A repeated measures ANOVA was performed to test the effect of three techniques and the effect of group was tested through a multivariate ANOVA with significant level set at p &le; 0/05. Results: The effect of technique was found to be significant (p=0.000). The punch against guard of opponent and shadow boxing produced maximum and minimum of angular velocity in both attackting arm and forearm, respectively. The effect of group was also significant (p=0.000). &nbsp;Indicating that elite Boxors presented higher arm and forearm angular velocity during punch. Conclusion: It seems that when there is not a real target for punching, such as in shadow boxing condition, Amateurs were confused dealing with this circumstance and had minor arm forearm angular velocity and Imuls in attacking arm. The results obtained suggest the presence of a skill-dependent activation strategy in the execution of the three punch technique. As, a reciprocal effect exist between the factors of different skill level and punching technique

The long-term use of foot orthoses affects walking kinematics and kinetics of children with flexible flat feet: A randomized controlled trial.

BACKGROUND:Due to inconclusive evidence on the effects of foot orthoses treatment on lower limb kinematics and kinetics in children, studies are needed that particularly evaluate the long-term use of foot orthoses on lower limb alignment during walking. Thus, the main objective of this study was to evaluate the effects of long-term treatment with arch support foot orthoses versus a sham condition on lower extremity kinematics and kinetics during walking in children with flexible flat feet. METHODS:Thirty boys aged 8-12 years with flexible flat feet participated in this study. While the experimental group (n = 15) used medial arch support foot orthoses during everyday activities over a period of four months, the control group (n = 15) received flat 2-mm-thick insoles (i.e., sham condition) for the same time period. Before and after the intervention period, walking kinematics and ground reaction forces were collected. RESULTS:Significant group by time interactions were observed during walking at preferred gait speed for maximum ankle eversion, maximum ankle internal rotation angle, minimum knee abduction angle, maximum knee abduction angle, maximum knee external rotation angle, maximum knee internal rotation angle, maximum hip extension angle, and maximum hip external rotation angle in favor of the foot orthoses group. In addition, statistically significant group by time interactions were detected for maximum posterior, and vertical ground reaction forces in favor of the foot orthoses group. CONCLUSIONS:The long-term use of arch support foot orthoses proved to be feasible and effective in boys with flexible flat feet to improve lower limb alignment during walking

Combining valgus knee brace and lateral foot wedges reduces external forces and moments in osteoarthritis patients

Osteoarthritis progression can be related to the external knee adduction and flexion moments during walking. Lateral foot wedges and knee braces have been used as treatment for osteoarthritis, but little is known about their influence on knee joint moments generated in the sagittal and frontal planes. Therefore, the aim of the present study was determine the effects of the isolated and combined use of valgus knee brace and lateral wedge foot orthotic on peak forces and moments during gait in knee osteoarthritis patients. Twenty four males (age: 62.1 +/- 2.0 years) with varus alignment, symptomatic medial compartment knee osteoarthritis participated in this study. Subjects walked over ground at preferred speed in four conditions: (1) no assistive device (control); (2) using lateral wedges, (3) using knee braces, and (4) using both lateral wedges and knee braces. Ground reaction forces (GRF) and moments, as well as lower limb kinematics were recorded. Peak GRF, vertical loading rate, free moment, external knee adduction and flexion moments were compared across conditions. The concurrent use of lateral wedge and knee brace reduced the first peak GRF in the vertical (6%, p = 0.002), anteriorposterior (30%, p = 0.028) and medial-lateral directions (44%, p = 0.029). Moreover, the use of these devices reduced the peak external knee adduction moment (25%, p = 0.019), but not the external flexion moment and free moment (p > 0.05). The combined use of lateral wedges and knee braces can reduce medial-lateral knee joint loading, but despite reduced peak forces in the sagittal plane, these device do not reduce joint moments

A comparison of running kinetics in children with and without genu varus: A cross sectional study

<div><p>Introduction</p><p>Varus knee alignment has been identified as a risk factor for the progression of medial knee osteoarthritis. However, the underlying mechanisms have not been elucidated yet in children. Thus, the aims of the present study were to examine differences in ground reaction forces, loading rate, impulses, and free moment values during running in children with and without genu varus.</p><p>Methods</p><p>Thirty-six boys aged 9–14 volunteered to participate in this study. They were divided in two age-matched groups (genu varus versus healthy controls). Body weight adjusted three dimensional kinetic data (Fx, Fy, Fz) were collected during running at preferred speed using two Kistler force plates for the dominant and non-dominant limb.</p><p>Results</p><p>Individuals with knee genu varus produced significantly higher (<i>p</i> = .01; <i>d</i> = 1.09; 95%) body weight adjusted ground reaction forces in the lateral direction (Fx) of the dominant limb compared to controls. On the non-dominant limb, genu varus patients showed significantly higher body weight adjusted ground reaction forces values in the lateral (<i>p</i> = .01; <i>d</i> = 1.08; 86%) and medial (<i>p</i> < .001; <i>d</i> = 1.55; 102%) directions (Fx). Further, genu varus patients demonstrated 55% and 36% greater body weight adjusted loading rates in the dominant (<i>p</i> < .001; <i>d</i> = 2.09) and non-dominant (<i>p <</i> .<i>001</i>; <i>d</i> = 1.02) leg, respectively. No significant between-group differences were observed for adjusted free moment values (<i>p</i>>.05).</p><p>Discussion</p><p>Higher mediolateral ground reaction forces and vertical loading rate amplitudes in boys with genu varus during running at preferred running speed may accelerate the development of progressive joint degeneration in terms of the age at knee osteoarthritis onset. Therefore, practitioners and therapists are advised to conduct balance and strength training programs to improve lower limb alignment and mediolateral control during dynamic movements.</p></div

The long-term use of foot orthoses affects walking kinematics and kinetics of children with flexible flat feet

Background Due to inconclusive evidence on the effects of foot orthoses treatment on lower limb kinematics and kinetics in children, studies are needed that particularly evaluate the long-term use of foot orthoses on lower limb alignment during walking. Thus, the main objective of this study was to evaluate the effects of long-term treatment with arch support foot orthoses versus a sham condition on lower extremity kinematics and kinetics during walking in children with flexible flat feet. Methods Thirty boys aged 8–12 years with flexible flat feet participated in this study. While the experimental group (n = 15) used medial arch support foot orthoses during everyday activities over a period of four months, the control group (n = 15) received flat 2-mm-thick insoles (i.e., sham condition) for the same time period. Before and after the intervention period, walking kinematics and ground reaction forces were collected. Results Significant group by time interactions were observed during walking at preferred gait speed for maximum ankle eversion, maximum ankle internal rotation angle, minimum knee abduction angle, maximum knee abduction angle, maximum knee external rotation angle, maximum knee internal rotation angle, maximum hip extension angle, and maximum hip external rotation angle in favor of the foot orthoses group. In addition, statistically significant group by time interactions were detected for maximum posterior, and vertical ground reaction forces in favor of the foot orthoses group. Conclusions The long-term use of arch support foot orthoses proved to be feasible and effective in boys with flexible flat feet to improve lower limb alignment during walking

Time-normalized traces of the ground reaction forces for both groups during the stance phase of a running cycle.

<p>Reaction forces (Fx, Fy, Fz) are demonstrated for the (a) dominant and (b) non-dominant lower limbs. “IP”, “AP”, “BP” and “PP” represent abbreviations that stand for “Impact Peak”, “Active Peak”, “Braking Peak” and “Propulsion Peak”, respectively. The solid lines represent the mean values, whereas the dashed lines indicate standard deviation values.</p

A comparison of running kinetics in children with and without genu varus: A cross sectional study - Fig 4

<p>Means and standard deviations of (a) impulse x, (b) impulse y, and (c) impulse z values for both groups during the stance phase of a running cycle.</p