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Lower extremity and trunk sagittal plane coordination strategies and kinetic distribution during landing in males and females

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JOURNAL OF SPORTS SCIENCES 2024年第2期42卷 169-178页

作者： Dennis, Justin D. Choe, Kevin H. Montgomery, Melissa M. Lynn, Scott K. Crews, Brock M. Pamukoff, Derek N. Univ North Carolina Chapel Hill Dept Exercise & Sports Sci Chapel Hill NC USA Calif State Univ Dept Kinesiol Fullerton CA USA Whittier Coll Dept Kinesiol Whittier CA USA Excel Sports Management Dept Comp Sci Irvine CA USA Western Univ Sch Kinesiol London ON Canada Univ North Carolina Chapel Hill Dept Exercise & Sports Sci CB 8700 Fetzer Hall Chapel Hill NC 27599 USA

Force attenuation during landing requires coordinated motion of the ankle, knee, hip, and trunk, and strategies may differ between sexes. Sagittal plane coordination of the ankle/knee, knee/hip, and knee/trunk, and lower extremity and trunk kinematics and kinetics was compared throughout landing between 28 males and 28 females. Coordination was assessed with a modified vector coding technique and binning analysis. Total support moments (TSM), each joint's percent contribution, and timing of the TSM were compared. Females landed with less isolated knee flexion in the ankle/knee, knee/hip, and knee/trunk couplings, but more simultaneous ankle/knee flexion, less simultaneous knee flexion/hip extension, and more simultaneous trunk/knee flexion. Females landed with larger plantarflexion angles from 0-16% and smaller trunk flexion angles from 0-78%. In females, absolute TSM were larger from 0-6% and smaller from 42-100%, and normalized TSM were larger from 0-8% and 26-42%. Females had greater ankle contribution to the TSM from 14-15% and 29-35%, smaller absolute peak TSM, and the peak TSM occurred earlier. Females compensated for less isolated knee flexion with greater simultaneous ankle/knee flexion early in landing and knee/trunk flexion later in landing. Coordination and TSM differences may influence force attenuation strategies and have implications for knee injury disparity between sexes.

关键词： vector coding total support moment drop vertical jump knee biomechanics

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Correction of ADAMTS13 Deficiency by In Utero Gene Transfer of Lentiviral vector encoding ADAMTS13 Genes

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MOLECULAR THERAPY 2009年第1期17卷 34-41页

作者： Niiya, Masami Endo, Masayuki Shang, Dezhi Zoltick, Philip W. Muvarak, Nidal E. Cao, Wenjing Jin, Sheng-Yu Skipwith, Christopher G. Motto, David G. Flake, Alan W. Zheng, X. Long Childrens Hosp Philadelphia Dept Pathol & Lab Med Philadelphia PA 19104 USA Univ Penn Philadelphia PA 19104 USA Childrens Hosp Philadelphia Dept Surg Philadelphia PA 19104 USA Univ Iowa Dept Internal Med Iowa City IA 52242 USA

Deficiency of A Disintegrin And Metalloprotease with Thrombo Spondin (ADAMTS13) results in thrombotic thrombocytopenic purpura (TTP). Plasma infusion or exchange is the only effective treatment to date. We show in this study that an administration of a self-inactivating lentiviral vector encoding human full-length ADAMTS13 and a variant truncated after the spacer domain (MDTCS) in mice by in utero injection at embryonic days 8 and 14 resulted in detectable plasma proteolytic activity (similar to 5-70%), which persisted for the length of the study (up to 24 weeks). Intravascular injection via a vitelline vein at E14 was associated with significantly lower rate of fetal loss than intra-amniotic injection, suggesting that the administration of vector at E14 may be a preferred gestational age for vector delivery. The mice expressing ADAMTS13 and MDTCS exhibited reduced sizes of von Willebrand factor (vWF) compared to the Adamts13(-/-) mice expressing enhanced green fluorescent protein (eGFP). Moreover, the mice expressing both ADAMTS13 and MDTCS showed a significant prolongation of ferric chloride-induced carotid arterial occlusion time as compared to the Adamts13(-/-) expressing eGFP. The data demonstrate the successful correction of the prothrombotic phenotypes in Adamts13(-/-) mice by a single in utero injection of lentiviral vectors encoding human ADAMTS13 genes, providing the basis for developing a gene therapy for hereditary TTP in humans.

关键词： ADAM Proteins Animals Blotting Western Female Gene Therapy Genetic vectors Humans Immunoprecipitation Lentivirus Mice Mutant Strains Microscopy Fluorescence Purpura Thrombotic Thrombocytopenic Uterus Purpura vector coding Gene transfer ADAMTS13 gene Genetic vectors Genetic Therapy Immunoprecipitation ADAM Proteins Vitelline Vein NPAT gene Transgenes Uterus blotting

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The effect of running speed on joint coupling coordination and its variability in recreational runners

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HUMAN MOVEMENT SCIENCE 2019年 66卷 449-458页

作者： Floria, Pablo Sanchez-Sixto, Alberto Harrison, Andrew J. Ferber, Reed Univ Pablo de Olavide Phys Performance & Sports Res Seville Spain CEU San Pablo Univ Dept Sport Madrid Spain Univ Limerick Biomech Res Unit Limerick Ireland Running Injury Clin Calgary AB Canada Univ Calgary Calgary AB Canada

The purpose of this study was to examine the effect of speed on coordination and its variability in running gait using vector coding analysis. Lower extremity kinematic data were collected for thirteen recreational runners while running at three different speeds in random order: preferred speed, 15% faster and 15% lower than preferred speed. A dynamical systems approach, using vector coding and circular statistics, were used to quantify coordination and its variability for selected hip-knee and knee-ankle joint couplings. The influence of running speed was calculated from the continuous data sets of the running cycle, allowing for the identification of time percentages where differences existed. Results indicate that increases in running speed produced moderate alterations in the frequency of movement patterns which were not enough to alter classification of coordination. No effects of speed on coordination variability were observed. This study has demonstrated that coordination and coordination variability is generally stable in the range of +/- 15% around of preferred speed in recreational runners.

关键词： vector coding Circular statistics Dynamical systems Lower extremity

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Segment coordination and variability among prospectively injured and uninjured runners

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JOURNAL OF SPORTS SCIENCES 2021年第1期39卷 38-47页

作者： Desai, Gauri A. Gruber, Allison H. Indiana Univ Dept Kinesiol Sch Publ Hlth Bloomington Bloomington IN 47405 USA

Coordinative variability (CAV) and underlying coordinative patterns are potential running-related overuse injury (RROI) mechanisms, but prospective analyses are needed. This study compared lower limb CAV and coordinative patterns between prospectively injured and uninjured runners. Knee, shank, and ankle kinematics were collected for 39 recreational runners at the beginning of a 6-month follow-up period. Subjects were classified as injured (n=21) or controls (n=18) based on RROI incidence during follow-up. CAV was quantified using modified vector coding. Time spent in each coordinative pattern category was quantified using binning frequency analysis. Coordinative patterns were classified as mechanically unsound if underlying joint/segment motions opposed anatomically allowable running motion. Wilcoxon Rank-Sum tests compared CAV and binning frequencies between groups within different stance portions for knee-shank, shank-ankle, and knee-ankle couplings (alpha <= 0.05). During initial-stance, the injured group displayed significantly greater knee-ankle CAV (effect size (ES)=1.1), knee-shank CAV (ES=0.97), and greater frequency of mechanically unsound knee-shank (ES=0.72) and shank-ankle (ES=0.63) motion. During mid-stance, the injured group displayed lower frequency of mechanically sound knee-ankle motion (ES=0.31). In late-stance, the injured group displayed greater shank-ankle CAV (ES=0.11). Mechanically unsound coordinative patterns along with greater knee-ankle and shank-ankle CAV potentially lead to RROI.

关键词： Running injury vector coding coordination variability lower extremity coordination patterns

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Assessing lower extremity coordination and coordination variability in individuals with anterior cruciate ligament reconstruction during walking

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GAIT & POSTURE 2019年 67卷 154-159页

作者： Davis, Kylie Williams, John L. Sanford, Brooke A. Zucker-Levin, Audrey Univ Tennessee Ctr Hlth Sci Memphis TN 38163 USA Univ Memphis Memphis TN 38152 USA Univ Kentucky Lexington KY 40506 USA Univ Saskatchewan Saskatoon SK Canada

Background: Despite our knowledge of several biomechanical risk factors related to anterior cruciate ligament (ACL) injury, such as decreased knee flexion, increased knee abduction, and increased hip flexion, adduction and internal rotation during walking, jogging, and landing from a jump, the incidence of ACL tears remains high. Quantifying variability in the lower extremity provides a continuous measure of joint coordination and function that may elicit an additional aspect of ACL injury mechanisms. Research question: The aim of this study was to assess joint coordination patterns and variability in individuals following ACL reconstruction (ACLR). Methods: Twenty participants with unilateral ACLR and twenty uninjured participants matched by sex and body mass index (BMI) walked over-ground at self-selected speed. Two force plates embedded in the walking platform recorded ground reaction forces (GRF), and a motion capture system collected kinematic data. vector coding was used to describe coordination patterns and measure coordination variability in hip-knee and knee-ankle coupled motion. Results: Individuals with ACLR had greater variability in hip-knee coordination compared to their healthy counterparts for both the reconstructed and contralateral limbs. The individuals with ACLR also exhibited altered coordination patterns, one of which was characterized by constrained hip motion. Significance: These results are evidence that differences in joint coordination exist between individuals with and without ACLR, even after the former are cleared to return to sport. This new insight into coordinative function after ACLR may be useful for improving rehabilitation strategies as well as identifying those at risk of injury during return to sport testing.

关键词： Coordination Variability vector coding Anterior cruciate ligament reconstruction

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Adults with knee osteoarthritis use different coordinative strategies to transition from swing to stance compared to young asymptomatic adults

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GAIT & POSTURE 2021年 88卷 72-77页

作者： Hafer, Jocelyn F. Zernicke, Ronald F. Univ Delaware Dept Kinesiol & Appl Physiol Newark DE USA Univ Michigan Dept Orthopaed Surg Ann Arbor MI 48109 USA Univ Michigan Sch Kinesiol Ann Arbor MI 48109 USA Univ Michigan Dept Biomed Engn Ann Arbor MI 48109 USA

Background: Neuromuscular changes that occur with aging or joint pathology likely alter the coordinative strategies that adults use to walk and to recover from perturbations during gait. Differences in coordination patterns or in how coordination changes in response to a challenge may provide insight into neuromuscular targets for falls prevention interventions. Research question: Do young asymptomatic adults, older asymptomatic adults, and older adults with knee OA alter their lower extremity segment coordination differently in response to an increase in walking speed?. Methods: We captured lower extremity kinematics using inertial measurement units as 29 participants (10 young, 10 older, 9 older with knee osteoarthritis) walked on a treadmill at self-selected preferred and faster speeds. We calculated lower extremity segment coordination and coordination variability using vector coding. We compared coordination and its variability among groups and speeds. Results: There were no significant interactions between group and speed. Overall group or speed differences in coordination or variability occurred mostly during terminal swing or early stance. Coordination patterns differed between young adults and adults with knee osteoarthritis in all segment couples during terminal swing and at the foot vs. shank during early stance. During these same gait cycle phases for the foot vs. shank and shank vs. thigh segment couples, coordination patterns shifted towards those of young adults when participants walked faster. Where coordination variability differed by group or speed, it was lower in the young adults than in the older adults with or without knee osteoarthritis and at faster walking speed. Significance: Our results identified that older adults with knee osteoarthritis have a different strategy for transitioning from swing to stance compared to young adults, especially at distal limb segments. These results may help target fall prevention interventions to specific gait

关键词： vector coding Coordination variability Falls risk Aging Walking speed

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The effect of lumbopelvic region rotation relative flexibility on thorax-pelvis and pelvis-femur coordination during walking

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GAIT & POSTURE 2022年第0期98卷 121-127页

作者： Konishi, Rei Ozawa, Junya Kito, Nobuhiro Hiroshima Int Univ Fac Rehabil Dept Rehabil Hiroshima Japan Hiroshima Int Univ Grad Sch Med Technol & Hlth Welf Sci Major Med Engn & Technol Hiroshima Japan

Background: Lumbopelvic region rotation relative flexibility (LRRF), which is defined as lumbopelvic region that is relatively less stiffness than the hip region, is associated with low back pain (LBP) symptoms. However, how LRRF is influenced by lumbopelvic region motion during walking is unclear. Research question: What is the influence of LBP and LRRF on coorMethods: The presence of LRRF was determined based on whether the lumbopelvic rotation occurred in the first 50% of knee flexion or hip external rotation movement. Participants with LBP and LRRF were classified into the LBP group. Participants with LRRF but without LBP were classified into the early pelvis rotation (ROT) group, and those without LBP and relative flexibility were classified as controls. The thorax-pelvis coordination and pelvis-femur coordination during the stance cycles were calculated from the segmental angles obtained by three-dimensional motion analysis using a modified vector coding ***: In the sagittal plane, the thorax-pelvis coordination of the LBP group showed more anti-phase patterns at both the early stance and midstance compared with controls and the ROT group. In the sagittal and horizontal planes, pelvis-femur coordination of the LBP and ROT groups showed more in-phase patterns during the early stance and midstance compared with ***: Regardless of LBP, the presence of LRRF alters the intersegmental coordination during walking. In individuals with LRRF, stiffness of the hip may increase during walking. People who have LRRF without LBP may develop LBP in the future, and it is important for prevention to identify these differences in kinematics during walking.

关键词： Low back pain Lumbopelvic Relative flexibility vector coding Walking Coordination

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Coordination variability during running in adolescents with autism spectrum disorder

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AUTISM 2022年第5期26卷 1201-1215页

作者： Bennett, Hunter J. Jones, Taylor Valenzuela, Kevin A. Haegele, Justin A. Old Dominion Univ Norfolk VA 23529 USA Calif State Univ Long Beach Long Beach CA 90840 USA

Autistic persons exhibit variable movement, loading, and coordination patterns during walking. While much research has examined walking, little to no research exists regarding running for autistic persons despite its prevalence and benefits as a mode of physical activity. This study determined if autistic adolescents demonstrate increased coordination variability during running compared to matched controls. Seventeen autistic adolescents (aged = 13-18 years) and seventeen sex, age, and body mass index matched controls performed running at two matched speeds: self-selected of autistic adolescents and at 3.0 m/s. Modified vector coding was used to determine the patterns of movement for foot-shank, shank-thigh, left/right thigh, and contralateral arm-thigh coupling. Coordination variability, measuring cycle-to-cycle variability, was determined during loading response and pushoff phases. Mixed-model analyses of variance were used to determine group by speed interactions and main effects. Coordination variability was nearly 2x larger (all p < 0.001) in autistic adolescents compared to controls. Speed main effects were found for several sagittal plane couples during loading response. In agreement with walking analyses, this study illustrates that autistic adolescents run with increased intra-limb, inter-limb, and cross-body coordination variability. Like walking, increased coordination variability during running may negatively impact this mode of physical activity for autistic persons. Lay abstract Walking and running are popular forms of physical activity that involve the whole body (pelvis/legs and arms/torso) and are coordinated by the neuromuscular system, generally without much conscious effort. However, autistic persons tend not to engage in sufficient amounts of these activities to enjoy their health benefits. Recent reports indicate that autistic individuals tend to experience altered coordination patterns and increased variability during walking tasks when compar

关键词： autism spectrum disorder coordination variability vector coding walking

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Computation of color and brightness differences by rabbit visual cortex neurons

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Neuroscience and Behavioral Physiology 2006年第3期36卷 235-245页

作者： Polyanskii, V.B. Evtikhin, D.V. Sokolov, E.N. Department of Higher Nervous Activity and Psychophysiology M. V. Lomonosov Moscow State University Moscow Russian Federation

Extracellular recording of the activity of 54 neurons in the rabbit visual cortex in responses to substitutions of eight colored and eight monochromatic stimuli in pairs was studied. Stimuli were uniform flashes of light displayed on an SVGA monitor and illuminated the whole retina. The responses of phasic neurons showed an initial discharge (50-90 msec from the moment of the change in stimulus), associated with the brightness or color difference between the stimuli. These "discrimination discharges" were used to construct an 8 × 8 matrix for each neuron, showing the mean number of spikes per sec in responses to changes in different pairs of stimuli. Processing of the matrix by factor analysis identified the major factors determining the axes of the sensory space. A brightness space with only two dimensions, with darkness and brightness orthogonal axes, was seen for 30% of neurons. A four-dimensional color space was seen in 22% of neurons, with two color and two achromatic axes. The sensory space of these neurons was similar to the spaces obtained by analyzing the early components of visual evoked potentials in rabbits induced by changes in color stimuli and behavioral operant responses in conditioned reflex color differentiation. The fundamental coincidence of the sensory spaces obtained by different methods identifies the general nature of the principle of vector coding and the existence of special neuronal mechanisms for detection of color and brightness differences in the visual field. © 2006 Springer Science+Business Media, Inc.

关键词： Four-dimensional color space Rabbit Two-dimensional achromatic space vector coding Visual cortex neurons

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Knee-ankle kinematics and coupling responses to SportsMetrics training programs in females athletes with dynamic knee valgus: A sport-specific approach

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JOURNAL OF BODYWORK AND MOVEMENT THERAPIES 2024年 40卷 1363-1369页

作者： Rad, Niloofar Fakhraei Khosravani, Masoumeh Mohammadi, Hemn Sarvestan, Javad Univ Kurdistan Fac Humanity Sci Dept Phys Educ & Sport Sci Sanandaj Iran Univ Calgary Schulich Sch Engn Dept Biomed Engn Calgary AB Canada Univ Calgary Schulich Sch Engn Dept Geomat Engn Calgary AB Canada Univ Lisbon Fac Motricidade Humana Biomech & Funct Morphol Lab CIPER Lisbon Portugal Univ Ostrava Human Mot Diagnost Ctr Ostrava Czech Republic

Objectives: This study aimed to investigate the impact of SportsMetrics programs on knee and ankle kinematics, as well as knee-ankle coupling responses during double leg landings among female athletes with dynamic knee valgus (ligament dominance). Methods: Eighty-four female athletes, including 30 volleyball players, 30 basketball players, and 24 soccer players, were randomly divided into two equal training (TG) and a control groups (CG). The TG underwent 18 sessions of SportsMetrics exercises, while the CG maintained their regular exercise routine. Dynamic knee valgus, lower limb kinematics, and coordination were assessed using the double leg squat and landing error scoring system tests. Main outcome measures: The main outcome measures encompassed knee sagittal and frontal kinematics, ankle sagittal kinematics, as well as knee-ankle coordination and its variability. Results: Significant reduction in knee range of motion in the frontal plane was observed across all three sports during landing. The SportsMetrics program tailored for basketball players led to a specific increase in knee flexion. Conclusion: The implementation of SportsMetrics effectively modifies ACL injury risk factors, addressing dynamic knee valgus and landing techniques in female athletes. Female athletes displaying dynamic knee valgus are advised to incorporate sport-specific SportsMetrics programs into their training regimens for optimal results.

关键词： Kinematics Landing coordination vector coding Knee abduction

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