60 results on '"Tucker, Kylie"'
Search Results
2. The Volitional Control of Individual Motor Units Is Constrained within Low-Dimensional Neural Manifolds by Common Inputs.
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Rossato, Julien, Avrillon, Simon, Tucker, Kylie, Farina, Dario, and Hug, François
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MOTOR unit ,DIMENSIONAL reduction algorithms ,KNEE joint ,ANKLE joint ,VASTUS lateralis ,VASTUS medialis - Abstract
The implementation of low-dimensional movement control by the central nervous system has been debated for decades. In this study, we investigated the dimensionality of the control signals received by spinal motor neurons when controlling either the ankle or knee joint torque. We first identified the low-dimensional latent factors underlying motor unit activity during torque-matched isometric contractions in male participants. Subsequently, we evaluated the extent to which motor units could be independently controlled. To this aim, we used an online control paradigm in which participants received the corresponding motor unit firing rates as visual feedback. We identified two main latent factors, regardless of the muscle group (vastus lateralis-medialis and gastrocnemius lateralis-medialis). The motor units of the gastrocnemius lateralis could be controlled largely independently from those of the gastrocnemius medialis during ankle plantarflexion. This dissociation of motor unit activity imposed similar behavior to the motor units that were not displayed in the feedback. Conversely, it was not possible to dissociate the activity of the motor units between the vastus lateralis and medialis muscles during the knee extension tasks. These results demonstrate that the number of latent factors estimated from linear dimensionality reduction algorithms does not necessarily reflect the dimensionality of volitional control of motor units. Overall, individual motor units were never controlled independently of all others but rather belonged to synergistic groups. Together, these findings provide evidence for a low-dimensional control of motor units constrained by common inputs, with notable differences between muscle groups. [ABSTRACT FROM AUTHOR] more...
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- 2024
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3. Comparison of physiological and behavioral nutrition-related factors in people with and without adolescent idiopathic scoliosis, from cohort data at 8 to 20 years.
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Ng, Phoebe T T, Tucker, Kylie, Zahir, Syeda Farah, Izatt, Maree T, Straker, Leon, and Claus, Andrew
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ADOLESCENT idiopathic scoliosis ,EATING disorders in adolescence ,BODY composition ,BONE density ,EATING disorders ,LEAN body mass ,BODY mass index - Abstract
Nutrition-related variables including lower body mass index (BMI), lower bone mineral density (BMD), altered body composition and hormone levels have been reported in adolescent idiopathic scoliosis (AIS). The aims of this study were to determine if physiological and behavioral nutrition-related factors differ between people with and without AIS, and to quantify their relationship with AIS, in unbiased cohort sample. BMI, presence of an eating disorder, leptin, adiponectin, BMD, vitamin D, lean mass, and fat mass were compared between those with and without AIS at ages 8, 10, 14, 17, and 20 years, and multiple logistic regression was performed between these variables and AIS. Lower total body BMD (median, 1.0 g/cm
2 vs 1.1 g/cm2 ; p = .03) and lean mass (median, 38.8 kg vs 46.0 kg; p = .04) at age 20 years were observed in those with AIS compared to those without scoliosis. At age 20, the odds of AIS were 3.23 times higher for adolescents with an eating disorder compared to those with no eating disorder (95% CI, 1.02–8.63) when adjusted for BMI. Every 1 kg/m2 increase in BMI decreased the odds of AIS by 0.88 times (95% CI, 0.76–0.98), after adjusting for eating disorder diagnosis. In conclusion, lower BMI in mid-adolescence and presence of eating disorder outcomes, lower BMD, and lower lean mass in late adolescence were associated with the presence of AIS. Current data do not explain the mechanisms for these associations but suggest that serum leptin, adiponectin, and vitamin D are unlikely to be contributing factors. Conclusive determination of the prevalence of eating disorders in AIS will require further studies with larger sample sizes. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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4. Quantifying Muscle Size Asymmetry in Adolescent Idiopathic Scoliosis Using Three-dimensional Magnetic Resonance Imaging.
- Author
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Duncombe, Phoebe, Izatt, Maree T., Pivonka, Peter, Claus, Andrew, Little, J. Paige, and Tucker, Kylie
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- 2023
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5. Reproducibility of Hypermobility Assessment Scales for Children When Performed Using Telehealth versus In-Person Modes.
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Hornsby, Elizabeth A., Tucker, Kylie, and Johnston, Leanne M.
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RESEARCH evaluation ,CONFIDENCE intervals ,STATISTICAL reliability ,JOINT instability ,PEDIATRICS ,INTRACLASS correlation ,DESCRIPTIVE statistics ,REPEATED measures design ,MEDICAL appointments ,DATA analysis software ,TELEMEDICINE ,HOSPITAL care of children ,MEASUREMENT errors ,CHILDREN - Abstract
Evaluate reproducibility of hypermobility assessments using in-person versus telehealth modes. Hypermobility of 20 children (7–12 years) was evaluated using the Beighton Score, Upper Limb Hypermobility Assessment Tool (ULHAT), and Lower Limb Assessment Score (LLAS) via in-person and telehealth modes. Agreement between the two modes was examined using percentage of exact agreement (%EA and %EA ± 2), Limits of Agreement (LoA) and Smallest detectable change (SDC). Reliability was calculated using intra-class correlation coefficients (ICCs). Agreement between modes for total Scores was best for the Beighton (%EA = fair, %EA ± 2 = good), then the ULHAT (%EA = poor, %EA ± 2 = excellent), and LLAS (%EA = poor, %EA ± 2 = fair). Total scores for all scales showed wide LoA, large SDC (25-31%), and fair to good reliability (ICC = 0.54–0.61). Exact agreement for Generalized Joint Hypermobility classification was excellent for the Beighton (≥7/9 threshold) and fair for the ULHAT and LLAS (≥7/12 threshold). Percentage of individual test items with good/excellent agreement was highest for the Beighton (78%, 7/9 items), then the ULHAT (58%, 14/24) and LLAS (42%, 10/24). Total Scores of hypermobility scales showed low exact agreement between in-person and telehealth, but fair–excellent agreement within two points. Classification using the Beighton ≥7/9 threshold was excellent. Research is recommended to increase accuracy of online assessments. [ABSTRACT FROM AUTHOR] more...
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- 2023
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6. Neuromechanical Properties of the Vastus Medialis and Vastus Lateralis in Adolescents With Patellofemoral Pain.
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Crouzier, Marion, Hug, François, Sheehan, Frances T., Collins, Natalie J., Crossley, Kay, and Tucker, Kylie
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QUADRICEPS muscle physiology ,KNEE joint ,ANALYSIS of variance ,CROSS-sectional method ,MAGNETIC resonance imaging ,TENDONS ,DESCRIPTIVE statistics ,QUESTIONNAIRES ,RESEARCH funding ,PLICA syndrome ,BIOMECHANICS ,ELECTROMYOGRAPHY ,DATA analysis software ,ADOLESCENCE - Abstract
Background: An alteration in the force distribution among quadriceps heads is one possible underlying mechanism of patellofemoral pain. However, this hypothesis cannot be directly tested as there are currently no noninvasive experimental techniques to measure individual muscle force or torque in vivo in humans. In this study, the authors considered a combination of biomechanical and muscle activation measures, which enabled us to estimate the mechanical impact of the vastus medialis (VM) and vastus lateralis (VL) on the patella. Purpose/Hypothesis: The purpose of this study was to determine whether the relative index of torque distribution for the VM and VL differs between adolescents with and without patellofemoral pain. It was hypothesized that, relative to the VL, the VM would contribute less to knee extension torque in adolescents with patellofemoral pain compared with controls. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Twenty adolescents with patellofemoral pain and 20 matched control participants were included (38 female; age, 15.3 ± 1.8 years; weight, 58 ± 13 kg; height, 164 ± 8 cm). Muscle volumes and resting moment arms were quantified from magnetic resonance images, and fascicle lengths were obtained from panoramic B-mode ultrasonography. Muscle activation was estimated using surface electromyography during submaximal isometric tasks (wall-squat and seated tasks). Muscle torque was estimated as the product of muscle physiological cross-sectional area (ie, muscle volume/fascicle length), muscle activation (normalized to maximal activation), and moment arm. Results: Across tasks and force levels, the relative contribution of the VM to the overall medial and lateral vastii torque was 31.0% ± 8.6% for controls and 31.5 ± 7.6% for adolescents with patellofemoral pain (group effect, P >.34). Conclusion: For the tasks and positions investigated in this study, the authors found no evidence of lower VM torque generation (relative to the VL) in adolescents with patellofemoral pain compared with controls. [ABSTRACT FROM AUTHOR] more...
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- 2023
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7. Comparison of a Wearable Accelerometer/Gyroscopic, Portable Gait Analysis System (LEGSYS+ TM) to the Laboratory Standard of Static Motion Capture Camera Analysis.
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Homes, Ryan, Clark, Devon, Moridzadeh, Sina, Tosovic, Danijel, Van den Hoorn, Wolbert, Tucker, Kylie, and Midwinter, Mark
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MOTION capture (Human mechanics) ,TREADMILLS ,GAIT in humans ,CAMERAS ,WALKING speed ,BLAND-Altman plot - Abstract
Examination of gait patterns has been used to determine severity, intervention triage and prognostic measures for many health conditions. Methods that generate detailed gait data for clinical use are typically logistically constrained to a formal gait laboratory setting. This has led to an interest in portable analysis systems for near clinical or community-based assessments. The following study assessed with the wearable accelerometer/gyroscopic, gait analysis system (LEGSYS+
TM ) and the standard of static motion capture camera (MOCAP) analysis during a treadmill walk at three different walking speeds in healthy participants (n = 15). To compare each speed, 20 strides were selected from the MOCAP data and compared with the LEGSYS+ strides at the same time point. Both scatter and bland-Altman plots with accompanying linear regression analysis for each of the parameters. Each stride parameter showed minimal or a consistent difference between the LEGSYS+ and MOCAP, with the phase parameters showing inconsistencies between the systems. Overall, LEGSYS+ stride parameters can be used in the clinical setting, with the utility of phase parameters needing to be taken with caution. [ABSTRACT FROM AUTHOR] more...- Published
- 2023
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8. Evaluating validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) Clinical Test of Sensory Integration of Balance (CTSIB) criteria to categorise stance postural control of ambulant children with CP.
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Dewar, Rosalee M., Tucker, Kylie, Claus, Andrew P., van den Hoorn, Wolbert, Ware, Robert S., and Johnston, Leanne M.
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RESEARCH evaluation ,RESEARCH methodology evaluation ,POSTURAL balance ,RESEARCH methodology ,STANDING position ,TEST validity ,PSYCHOMETRICS ,DESCRIPTIVE statistics ,RESEARCH funding ,CEREBRAL palsy - Abstract
Evaluate the validity of the Clinical Test of Sensory Integration of Balance (CTSIB) scored using Kids-Balance Evaluation Systems Test (Kids-BESTest) criteria compared to laboratory measures of postural control. Participants were 58 children, 7–18 years, 17 with ambulant cerebral palsy (CP) (GMFCS I–II), and 41 typically developing (TD). Postural control in standing was assessed using CTSIB items firm and foam surfaces, eyes open (EO) then closed (EC). Face validity was evaluated comparing clinical Kids-BESTest scores between groups. Correlating force plate centre-of-pressure (CoP) data and clinical scores allowed evaluation of concurrent and content validity. Face validity: TD children scored higher for all CTSIB conditions when compared to children with CP. Concurrent validity: the agreement between clinical and CoP derived scores was poor to excellent (Firm-EO = 76%, Firm-EC = 76%, Foam-EO = 59%, Foam-EC = 94%). Clinical scores of "2-unstable" and "3-stable" were not distinguished reliably by force plate measures. Content validity: significant correlations were found between clinical scores and CoP data for the two intermediate conditions (Firm-EC: r
s −0.40 to −0.72; Foam-EO: rs −0.12 to −0.50), but not the easier (Firm-EO: rs −0.41 to −0.36) or harder conditions (Foam-EC: rs −0.25 to −0.27). Face validity of Kids-BESTest CTSIB criteria was supported. Content and concurrent validity were partially supported. Improved Kids-BESTest scoring terms were recommended to describe postural characteristics of "2-unstable." Face validity of the Kids-BESTest criteria for the CTSIB was confirmed. The Kids-BESTest criteria for the CTSIB can identify children with atypical postural control. Concurrent validity and content validity were partially supported, since children with CP resorted to a range of different balance strategies when "unstable." To improve CTSIB Kids-BESTest criteria, new terms were recommended to better describe postural characteristics of "2-unstable." [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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9. Adolescent perspectives on participating in a feasibility trial investigating shoe inserts for patellofemoral pain.
- Author
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O'Sullivan, Isobel C., da Costa, Nathalia Cordeiro, Franettovich Smith, Melinda M., Vicenzino, Bill, Crossley, Kay M., Kamper, Steven J., van Middelkoop, Marienke, Menz, Hylton B., Tucker, Kylie, O'Leary, Karina T., and Collins, Natalie J. more...
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TEENAGERS ,SPORTS participation ,KNEE pain ,PATELLA ,THEMATIC analysis - Abstract
Background: Patellofemoral pain (PFP) affects one-quarter of adolescents, yet there are few evidence-informed recommendations to treat PFP in this population. HAPPi Kneecaps! is a randomised, controlled, participant- and assessor-blind, parallel-group feasibility trial of shoe inserts for adolescents with PFP. The aim of this qualitative study was to explore adolescents' perspectives of participating in HAPPi Kneecaps!. Methods: All 36 adolescents with PFP from the HAPPi Kneecaps! study were invited to participate in semi-structured interviews. We used a descriptive qualitative methodology underpinned by a relativist framework to investigate adolescents' perspectives on participating in the trial. Inductive thematic analysis was used to examine patterns regarding how each adolescent experienced the HAPPi Kneecaps! study within their social, cultural, and historical contexts. Results: 14 out of 36 HAPPi Kneecaps! participants provided consent and participated in interviews (12 females; mean [SD] age 14.9 [2.4] years). Overall, most adolescents responded positively when discussing their experience, such as improvements in their knee pain and satisfaction with how the study was run. Major themes that were generated from the analysis and feedback were: (1) shoe inserts require little effort to use; (2) perceptions of the program were generally positive; (3) participation in the trial could be made easier; (4) warm weather matters; and (5) life happens. Conclusion: Adolescents with PFP who participated in the HAPPi Kneecaps! study found that shoe inserts were easy to wear. Most adolescents experienced an improvement in their symptoms and enhanced participation in sport and exercise. Adolescents with PFP prefer an option for warmer climates (e.g. flip flops or sandals), access to online logbooks, and clinicians who are easily accessible. Trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12619000957190. Date registered: 8/07/2019. [ABSTRACT FROM AUTHOR] more...
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- 2022
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10. Less common synaptic input between muscles from the same group allows for more flexible coordination strategies during a fatiguing task.
- Author
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Rossato, Julien, Tucker, Kylie, Avrillon, Simon, Lacourpaille, Lilian, Holobar, Aleš, and Hug, François
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RECTUS femoris muscles ,VASTUS medialis ,VASTUS lateralis ,MUSCLE fatigue ,MOTOR unit ,NEUROMUSCULAR system - Abstract
This study aimed to determine whether neural drive is redistributed between muscles during a fatiguing isometric contraction, and if so, whether the initial level of common synaptic input between these muscles constrains this redistribution. We studied two muscle groups: triceps surae (14 participants) and quadriceps (15 participants). Participants performed a series of submaximal isometric contractions and a torque-matched contraction maintained until task failure. We used high-density surface electromyography to identify the behavior of 1,874 motor units from the soleus, gastrocnemius medialis (GM), gastrocnemius lateralis (GL), rectus femoris, vastus lateralis (VL), and vastus medialis (VM). We assessed the level of common drive between muscles in the absence of fatigue using a coherence analysis. We also assessed the redistribution of neural drive between muscles during the fatiguing contraction through the correlation between their cumulative spike trains (index of neural drive). The level of common drive between VL and VM was significantly higher than that observed for the other muscle pairs, including GL-GM. The level of common drive increased during the fatiguing contraction, but the differences between muscle pairs persisted. We also observed a strong positive correlation of neural drive between VL and VM during the fatiguing contraction (r = 0.82). This was not observed for the other muscle pairs, including GL-GM, which exhibited differential changes in neural drive. These results suggest that less common synaptic input between muscles allows for more flexible coordination strategies during a fatiguing task, i.e., differential changes in neural drive across muscles. The role of this flexibility on performance remains to be elucidated. NEW & NOTEWORTHY Redundancy of the neuromuscular system theoretically allows for a redistribution of the neural drive across muscles (i.e., between-muscle compensation) during a fatiguing contraction. Our results suggest that a high level of common input between muscles (e.g., vastus lateralis and medialis) represents a neural constraint making it less likely to redistribute the neural drive across these muscles. In this way, redistribution was only observed across muscles that share little common synaptic input (e.g., gastrocnemius lateralis and medialis). [ABSTRACT FROM AUTHOR] more...
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- 2022
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11. Automatic quadriceps and patellae segmentation of MRI with cascaded U2‐Net and SASSNet deep learning model.
- Author
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Cheng, Ruida, Crouzier, Marion, Hug, François, Tucker, Kylie, Juneau, Paul, McCreedy, Evan, Gandler, William, McAuliffe, Matthew J., and Sheehan, Frances T.
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DEEP learning ,RECTUS femoris muscles ,QUADRICEPS muscle ,VASTUS medialis ,VASTUS lateralis ,MUSCULOSKELETAL system ,PATELLA - Abstract
Purpose: Automatic muscle segmentation is critical for advancing our understanding of human physiology, biomechanics, and musculoskeletal pathologies, as it allows for timely exploration of large multi‐dimensional image sets. Segmentation models are rarely developed/validated for the pediatric model. As such, autosegmentation is not available to explore how muscle architectural changes during development and how disease/pathology affects the developing musculoskeletal system. Thus, we aimed to develop and validate an end‐to‐end, fully automated, deep learning model for accurate segmentation of the rectus femoris and vastus lateral, medialis, and intermedialis using a pediatric database. Methods: We developed a two‐stage cascaded deep learning model in a coarse‐to‐fine manner. In the first stage, the U2‐Net roughly detects the muscle subcompartment region. Then, in the second stage, the shape‐aware 3D semantic segmentation method SASSNet refines the cropped target regions to generate the more finer and accurate segmentation masks. We utilized multifeature image maps in both stages to stabilize performance and validated their use with an ablation study. The second‐stage SASSNet was independently run and evaluated with three different cropped region resolutions: the original image resolution, and images downsampled 2× and 4× (high, mid, and low). The relationship between image resolution and segmentation accuracy was explored. In addition, the patella was included as a comparator to past work. We evaluated segmentation accuracy using leave‐one‐out testing on a database of 3D MR images (0.43 × 0.43 × 2 mm) from 40 pediatric participants (age 15.3 ± 1.9 years, 55.8 ± 11.8 kg, 164.2 ± 7.9 cm, 38F/2 M). Results: The mid‐resolution second stage produced the best results for the vastus medialis, rectus femoris, and patella (Dice similarity coefficient = 95.0%, 95.1%, 93.7%), whereas the low‐resolution second stage produced the best results for the vastus lateralis and vastus intermedialis (DSC = 94.5% and 93.7%). In comparing the low‐ to mid‐resolution cases, the vasti intermedialis, vastus medialis, rectus femoris, and patella produced significant differences (p = 0.0015, p = 0.0101, p < 0.0001, p = 0.0003) and the vasti lateralis did not (p = 0.2177). The high‐resolution stage 2 had significantly lower accuracy (1.0 to 4.4 dice percentage points) compared to both the mid‐ and low‐resolution routines (p value ranged from < 0.001 to 0.04). The one exception was the rectus femoris, where there was no difference between the low‐ and high‐resolution cases. The ablation study demonstrated that the multifeature is more reliable than the single feature. Conclusions: Our successful implementation of this two‐stage segmentation pipeline provides a critical tool for expanding pediatric muscle physiology and clinical research. With a relatively small and variable dataset, our fully automatic segmentation technique produces accuracies that matched or exceeded the current state of the art. The two‐stage segmentation avoids memory issues and excessive run times by using a first stage focused on cropping out unnecessary data. The excellent Dice similarity coefficients improve upon previous template‐based automatic and semiautomatic methodologies targeting the leg musculature. More importantly, with a naturally variable dataset (size, shape, etc.), the proposed model demonstrates slightly improved accuracies, compared to previous neural networks methods. [ABSTRACT FROM AUTHOR] more...
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- 2022
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12. HAPPi Kneecaps! A double-blind, randomised, parallel group superiority trial investigating the effects of sHoe inserts for adolescents with patellofemoral PaIn: phase II feasibility study.
- Author
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O'Sullivan, Isobel C., Crossley, Kay M., Kamper, Steven J., van Middelkoop, Marienke, Vicenzino, Bill, Franettovich Smith, Melinda M., Menz, Hylton B., Smith, Anne J., Tucker, Kylie, O'Leary, Karina T., Costa, Nathalia, and Collins, Natalie J. more...
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TEENAGERS ,FOOT orthoses ,QUALITY of life ,VOLUNTEER recruitment ,ADULTS ,KNEE ,FOOT ,TEENAGE girls - Abstract
Background: Patellofemoral pain (PFP) affects one-third of adolescents and can persist into adulthood, negatively impacting health and quality of life. Foot orthoses are a recommended treatment for adults with PFP, but have not been evaluated in adolescents. The primary objective was to determine the feasibility of conducting a full-scale randomised controlled trial (RCT) evaluating effects of contoured, prefabricated foot orthoses on knee pain severity and patient-perceived global change, compared to flat insoles. The secondary objective was to describe outcomes on a range of patient-reported outcome measures. Methods: We recruited adolescents aged 12–18 years with PFP of ≥2 months duration into a double-blind, randomised, parallel-group feasibility trial. Participants were randomised to receive prefabricated contoured foot orthoses or flat shoe insoles, and followed for 3 months. Participants and outcome assessors were blinded to group allocation. Primary outcomes were feasibility of a full-scale RCT (number of eligible/enrolled volunteers; recruitment rate; adherence with the intervention and logbook completion; adverse effects; success of blinding; drop-out rate), and credibility and expectancy of interventions. Secondary outcomes were patient-reported measures of pain, symptoms, function, quality of life, global rating of change, patient acceptable symptom state, and use of co-interventions. Results: 36 out of 279 (12.9%) volunteers (27 female, mean (SD) age 15 (2) years, body mass 60 (13) kg) were eligible and enrolled, at a recruitment rate of 1.2 participants/week. 17 participants were randomised to receive foot orthoses, and 19 to flat insoles. 15 participants returned logbooks; 7/15 (47%) adhered to the intervention. No serious adverse events were reported. 28% (10/36, 4 pandemic-related) of participants dropped out before 3 months. Blinding was successful. Both groups found the inserts to be credible. Conclusions: Based on a priori criteria for feasibility, findings suggest that a full-scale RCT comparing contoured foot orthoses to flat insoles in adolescents with PFP would not be feasible using the current protocol. Prior to conducting a full-scale RCT, feasibility issues should be addressed, with protocol modifications to facilitate participant retention, logbook completion and shoe insert wear. Trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12619000957190. Date registered: 8/07/2019. [ABSTRACT FROM AUTHOR] more...
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- 2021
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13. "Taking action" to reduce pain—Has interpretation of the motor adaptation to pain been too simplistic?
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Bergin, Michael, Tucker, Kylie, Vicenzino, Bill, and Hodges, Paul W.
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Movement adapts during acute pain. This is assumed to reduce nociceptive input, but the interpretation may not be straightforward. We investigated whether movement adaptation during pain reflects a purposeful search for a less painful solution. Three groups of participants performed two blocks (Baseline, Experimental) of wrist movements in the radial-ulnar direction. For the Control group (n = 10) both blocks were painfree. In two groups, painful electrical stimulation was applied at the elbow in Experimental conditions when the wrist crossed radial-ulnar neutral. Different stimulus intensities were given for specific wrist angles in a secondary direction (flexion-extension) as the wrist passed radial-ulnar neutral (Pain 5–1 group:painful stimulation at ~5 or ~1/10—n = 21; Pain 5–0 group:~5 or 0(no stimulation)/10—n = 6)). Participants were not informed about the less painful alternative and could use any strategy. We recorded the percentage of movements using the wrist flexion/extension alignment that evoked the lower intensity noxious stimulus, movement variability, and change in wrist/forearm alignment during pain. Participants adapted their strategy of wrist movement during pain provocation and reported less pain over time. Three adaptations of wrist movement were observed; (i) greater use of the wrist alignment with no/less noxious input (Pain 5–1, n = 8/21; Pain 5–0, n = 2/6); (ii) small (n = 9/21; n = 3/6) or (iii) large (n = 4/21; n = 1/6) change of wrist/forearm alignment to a region that was not allocated to provide an actual reduction in noxious stimulus. Pain reduction was achieved with "taking action" to relieve pain and did not depend on reduced noxious stimulus. [ABSTRACT FROM AUTHOR] more...
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- 2021
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14. Foot Orthoses and Footwear for the Management of Patellofemoral Osteoarthritis: A Pilot Randomized Trial.
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Wyndow, Narelle, Crossley, Kay M., Vicenzino, Bill, Tucker, Kylie, and Collins, Natalie J.
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FOOT orthoses ,FOOT abnormalities ,FOOTWEAR ,PATELLOFEMORAL joint diseases ,OSTEOARTHRITIS treatment - Abstract
Objective: To determine the feasibility of a full‐scale randomized controlled trial (RCT) comparing foot orthoses and footwear to footwear alone in individuals with patellofemoral (PF) osteoarthritis (OA). Methods: This 4‐month, parallel, 2‐arm pilot trial took place in Brisbane, Queensland and Hobart, Tasmania (August 2014 to October 2016). Forty‐six individuals with PF OA were randomized by concealed allocation to foot orthoses plus prescribed footwear (n = 24) or prescribed footwear alone (n = 22). Study feasibility was the primary outcome (e.g., recruitment rate, adherence, adverse events, dropout rate). Secondary outcomes included patient‐reported outcome measures of pain, function, and quality of life. Effect sizes with 95% confidence intervals were calculated at the 4‐month primary end point (standardized mean differences for between‐group effects; standardized response mean for within‐group effects). Results: From 782 volunteers, 47 were eligible (6%), and 46 participated. One participant withdrew (2%), and 1 (2%) was lost to follow‐up. Intervention adherence was high for both groups (9–10 hours of wear per day). No serious adverse events were reported. More than 80% of questionnaires were completed at 4 months. Between‐group effect sizes for patient‐reported outcome measures were typically small, while moderate‐to‐large within‐group response effects were observed in both groups. Conclusion: A full‐scale RCT for PF OA is feasible with modifications to eligibility criteria. However, our observed small between‐group effect sizes, combined with moderate‐to‐large within‐group responses for both interventions, indicate that a full‐scale trial is unlikely to find clinically meaningful differences. Secondary outcomes suggest that both interventions can be recommended for individuals with PF OA. [ABSTRACT FROM AUTHOR] more...
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- 2021
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15. Muscles from the same muscle group do not necessarily share common drive: evidence from the human triceps surae.
- Author
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Hug, François, Vecchio, Alessandro Del, Avrillon, Simon, Farina, Dario, and Tucker, Kylie
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MOTOR unit ,MUSCLES ,TRICEPS ,MUSCLE contraction ,CENTRAL nervous system ,DEGREES of freedom - Abstract
It has been proposed that movements are produced through groups of muscles, or motor modules, activated by common neural commands. However, the neural origin of motor modules is still debated. Here, we used complementary approaches to determine: 1) whether three muscles of the same muscle group [soleus, gastrocnemius medialis (GM), and gastrocnemius lateralis (GL)] are activated by a common neural drive, and 2) whether the neural drive to GM and GL could be differentially modified by altering the mechanical requirements of the task. Eighteen human participants performed an isometric standing heel raise and submaximal isometric plantarflexions (10%, 30%, and 50% of maximal effort). High-density surface electromyography recordings were decomposed into motor unit action potentials and coherence analysis was applied on the motor unit spike trains. We identified strong common drive to each muscle but minimal common drive between the muscles. Further, large between-muscle differences were observed during the isometric plantarflexions, such as a delayed recruitment time of GL compared with GM and soleus motor units and opposite time-dependent changes in the estimates of neural drive to muscles during the torque plateau. Finally, the feet position adopted during the heel-raise task (neutral vs. internally rotated) affected only the GL neural drive with no change for GM. These results provide conclusive evidence that not all anatomically defined synergist muscles are controlled by strong common neural drive. Independent drive to some muscles from the same muscle group may allow for more flexible control to comply with secondary goals such as joint stabilization. NEW & NOTEWORTHY In this study, we demonstrated that the three muscles composing the human triceps surae share minimal common drive during isometric contractions. Our results suggest that reducing the number of effectively controlled degrees of freedom may not always be the strategy used by the central nervous system to control movements. Independent control of some, but not all, synergist muscles may allow for more flexible control to comply with secondary goals (e.g., joint stabilization). [ABSTRACT FROM AUTHOR] more...
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- 2021
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16. HAPPi Kneecaps! Protocol for a participant- and assessor-blinded, randomised, parallel group feasibility trial of foot orthoses for adolescents with patellofemoral pain.
- Author
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O'Sullivan, Isobel C., Crossley, Kay M., Kamper, Steven J., van Middelkoop, Marienke, Vicenzino, Bill, Franettovich Smith, Melinda M., Menz, Hylton B., Smith, Anne J., Tucker, Kylie, O'Leary, Karina T., and Collins, Natalie J. more...
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FOOT orthoses ,TEENAGERS ,RANDOMIZED controlled trials ,PATELLA ,KNEE pain ,PATELLOFEMORAL joint - Abstract
Background: Patellofemoral pain (PFP) is a common cause of knee pain in adolescents, but there are limited evidence-based treatment options for this population. Foot orthoses can improve pain and function in adults with PFP, and may be effective for adolescents. The primary aim of this study is to determine the feasibility of conducting a full-scale randomised controlled trial (RCT) evaluating the effects of contoured foot orthoses on knee pain severity and patient-perceived global change, compared to flat shoe insoles, in adolescents with PFP. The secondary aim is to provide an estimate of treatment effects for foot orthoses, compared to flat insoles, in adolescents with PFP. Methods: This randomised, controlled, participant- and assessor-blinded, feasibility trial has two parallel groups. Forty adolescents (aged 12–18 years) with clinical symptoms of PFP will be recruited from Queensland, Australia. Participants will be randomised to receive either prefabricated contoured foot orthoses or flat shoe insoles. Both interventions will be fit by a physiotherapist, and worn for 3 months. Feasibility will be evaluated through assessing willingness of volunteers to enrol, number of eligible participants, recruitment rate, adherence with the study protocol, adverse effects, success of blinding, and drop-out rate. Secondary outcomes will evaluate knee-related pain, symptoms, function, quality of life, global rating of change, patient acceptable symptom state, and use of co-interventions, at 6 weeks and 3 months. Primary outcomes will be reported descriptively, while estimates of standard deviation and between-group differences (with 95% confidence intervals) will be reported for secondary outcomes. Discussion: Findings of this study will inform the feasibility of a full-scale RCT investigating the efficacy of contoured foot orthoses in adolescents with PFP. This full-scale study is necessary to improve the evidence base for management of adolescent PFP, and enhance outcomes for this population. Trial registration: ACTRN12619000957190. [ABSTRACT FROM AUTHOR] more...
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- 2020
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17. Force-sharing within the Triceps Surae: An Achilles Heel in Achilles Tendinopathy.
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CROUZIER, MARION, TUCKER, KYLIE, LACOURPAILLE, LILIAN, DOGUET, VALENTIN, FAYET, GUILLEMETTE, DAUTY, MARC, and HUG, FRANÇOIS
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- 2020
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18. Does adding hip exercises to quadriceps exercises result in superior outcomes in pain, function and quality of life for people with knee osteoarthritis? A systematic review and meta-analysis.
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Craig Hislop, Andrew, Collins, Natalie J., Tucker, Kylie, Deasy, Margaret, Semciw, Adam Ivan, and Hislop, Andrew Craig
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HIP exercises ,META-analysis ,PLICA syndrome ,EXERCISE ,STRENGTH training ,OSTEOARTHRITIS ,QUADRICEPS muscle physiology ,OSTEOARTHRITIS treatment ,KNEE diseases ,RESISTANCE training ,PAIN ,SYSTEMATIC reviews ,QUALITY of life ,MUSCLE strength ,EXERCISE therapy - Abstract
Objectives: To determine, in people with knee osteoarthritis (KOA): i) the effectiveness of adding hip strengthening exercises to quadriceps exercises and ii) the type of hip strengthening exercise with the greatest evidence for improving pain, function and quality of life.Design: Systematic review with meta-analysis.Data Sources: Medline, Embase, Cochrane, CINAHL and SportDiscus databases were searched from inception to January 2018.Eligibility Criteria For Selecting Studies: Randomised controlled trials investigating the effect of adding hip exercises to quadriceps exercises in people with KOA on pain, function and/or quality of life were included. Three subgroups of hip exercises were included: resistance, functional neuromuscular or multimodal exercise.Results: Eight studies were included. Pooled data provide evidence that combined hip and quadriceps exercise is significantly more effective than quadriceps exercise alone for improving walking function (standardised mean difference -1.06, 95% CI -2.01 to -0.12), but not for outcomes of pain (-0.09, 95% CI -0.96 to 0.79), patient-reported function (-0.74, 95% CI -1.56 to 0.08) or stair function (-0.7, 95% CI -1.67 to 0.26). Subgroup analyses reveal that hip resistance exercises are more effective than functional neuromuscular exercises for improving pain (p<0.0001) and patient-reported function (p<0.0001). Multimodal exercise is no more effective than quadriceps strengthening alone for pain (0.13, 95% CI -0.31 to 0.56), patient-reported function (-0.15, 95% CI -0.58 to 0.29) or stair function (0.13, 95% CI -0.3 to 0.57).Conclusion: Walking improved after the addition of hip strengthening to quadriceps strengthening in people with KOA. The addition of resistance hip exercises to quadriceps resulted in greater improvements in patient-reported pain and function. [ABSTRACT FROM AUTHOR] more...- Published
- 2020
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19. Individuals have unique muscle activation signatures as revealed during gait and pedaling.
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Hug, François, Vogel, Clément, Tucker, Kylie, Dorel, Sylvain, Deschamps, Thibault, Le Carpentier, Éric, and Lacourpaille, Lilian
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QUADRICEPS muscle ,RECTUS femoris muscles ,SUPPORT vector machines ,TIBIALIS anterior ,MUSCLE contraction ,CYCLING ,GAIT in humans ,SKELETAL muscle - Abstract
Although it is known that the muscle activation patterns used to produce even simple movements can vary between individuals, these differences have not been considered to prove the existence of individual muscle activation strategies (or signatures). We used a machine learning approach (support vector machine) to test the hypothesis that each individual has unique muscle activation signatures. Eighty participants performed a series of pedaling and gait tasks, and 53 of these participants performed a second experimental session on a subsequent day. Myoelectrical activity was measured from eight muscles: vastus lateralis and medialis, rectus femoris, gastrocnemius lateralis and medialis, soleus, tibialis anterior, and biceps femoris-long head. The classification task involved separating data into training and testing sets. For the within-day classification, each pedaling/gait cycle was tested using the classifier, which had been trained on the remaining cycles. For the between-day classification, each cycle from day 2 was tested using the classifier, which had been trained on the cycles from day 1. When considering all eight muscles, the activation profiles were assigned to the corresponding individuals with a classification rate of up to 99.28% (2,353/2,370 cycles) and 91.22% (1,341/1,470 cycles) for the withinday and between-day classification, respectively. When considering the within-day classification, a combination of two muscles was sufficient to obtain a classification rate _80% for both pedaling and gait. When considering between-day classification, a combination of four to five muscles was sufficient to obtain a classification rate _80% for pedaling and gait. These results demonstrate that strategies not only vary between individuals, as is often assumed, but are unique to each individual. NEW & NOTEWORTHY We used a machine learning approach to test the uniqueness and robustness of muscle activation patterns. We considered that, if an algorithm can accurately identify participants, one can conclude that these participants exhibit discernible differences and thus have unique muscle activation signatures. Our results show that activation patterns not only vary between individuals, but are unique to each individual. Individual differences should, therefore, be considered relevant information for addressing fundamental questions about the control of movement. [ABSTRACT FROM AUTHOR] more...
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- 2019
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20. Do individual differences in the distribution of activation between synergist muscles reflect individual strategies?
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Crouzier, Marion, Hug, François, Dorel, Sylvain, Deschamps, Thibault, Tucker, Kylie, and Lacourpaille, Lilian
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INDIVIDUAL differences ,LEG ,MUSCLES ,ELECTROMYOGRAPHY ,PLANTARFLEXION - Abstract
Individual differences in the distribution of activation between synergist muscles have been reported during a wide variety of tasks. Whether these differences represent actual individual strategies is unknown. The aims of this study were to: (i) test the between-day reliability of the distribution of activation between synergist muscles, (ii) to determine the robustness of these strategies between tasks, and to (iii) describe the inter-individual variability of activation strategies in a large sample size. Eighty-five volunteers performed a series of single-joint isometric tasks with their dominant leg [knee extension and plantarflexion at 25% of maximal voluntary contraction (MVC)] and locomotor tasks (pedalling and walking). Of these participants, 62 performed a second experimental session that included the isometric tasks. Myoelectrical activity of six lower limb muscles (the three superficial heads of the quadriceps and the three heads of the triceps surae) was measured using surface electromyography (EMG) and normalized to that measured during MVC. When considering isometric contractions, distribution of normalized EMG amplitude among synergist muscles, considered here as activation strategies, was highly variable between individuals (15.8% < CV < 42.7%) and robust across days (0.57 < ICC < 0.82). In addition, individual strategies observed during simple single-joint tasks were correlated with those observed during locomotor tasks [0.37 < r < 0.76 for quadriceps (n = 83); 0.30 < r < 0.66 for triceps surae (n = 82); all P < 0.001]. Our results provide evidence that people who bias their activation to a particular muscle do so during multiple tasks. Even though inter-individual variability of EMG signals has been well described, it is often considered noise which complicates the interpretation of data. This study provides evidence that variability results from actual differences in activation strategies. [ABSTRACT FROM AUTHOR] more...
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- 2019
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21. Location-specific responses to nociceptive input support the purposeful nature of motor adaptation to pain.
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Gallina, Alessio, Salomoni, Sauro E., Hall, Leanne M., Tucker, Kylie, Garland, S. Jayne, Hodges, Paul W., and Tucker, K
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- 2018
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22. Shear-wave velocity of the patellar tendon and quadriceps muscle is increased immediately after maximal eccentric exercise.
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Heales, Luke J., Badya, Rohitha, Ziegenfuss, Brandon, Hug, François, Coombes, Jeff S., van den Hoorn, Wolbert, Tucker, Kylie, and Coombes, Brooke K.
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TENDONS ,QUADRICEPS muscle ,KNEE ,EXTENSOR muscles ,JOINT stiffness ,KNEE physiology ,EXERCISE physiology ,EXERCISE tests ,MUSCLE contraction ,MUSCLE strength ,PATELLAR tendon ,SKELETAL muscle ,RECTUS femoris muscles - Abstract
Purpose: To determine whether stiffness of the patellar tendon and quadriceps muscles is altered immediately after and 48 h after a single bout of maximal eccentric exercise of the knee extensor muscles.Methods: Thirteen healthy individuals [group mean (SD) age 22.4 (3.5) years; 7 female] performed a single bout of maximal eccentric exercise of the non-dominant knee extensors, using an isokinetic dynamometer. Shear-wave velocity (an index of tissue stiffness) was recorded from the patellar tendon, vastus medialis (VM), rectus femoris (RF) and vastus lateralis (VL), before, following (post0), and 48 h after (post48) exercise. To investigate features of exercise induced muscle damage, maximal voluntary isometric contraction (MVIC) and self-reported pain and stiffness (numerical rating scales 0 = no pain/stiffness to 100 = worst imaginable pain/stiffness) were measured before, post0, and post48 exercise. Serum creatine kinase (CK) was measured before and post48 exercise.Results: Compared to preexercise, MVIC decreased and self-reported pain and stiffness increased at post0 and post48 and CK levels increased at post48 (all p < 0.01). Compared to preexercise, shear-wave velocity was greater at post0 for the patellar tendon [15.9 (24.6)%, p = 0.01] and RF [23.6 (16.7)%, p < 0.001], each returning to baseline by post48. No significant differences were observed for VL or VM post0 or post48 exercise.Conclusion: Maximal eccentric exercise produced an immediate increase in the stiffness of the patellar tendon and RF, resolving by 48 h. As this change was not observed in VL and VM, future studies may explore heterogeneity within synergist muscles following eccentric exercise. [ABSTRACT FROM AUTHOR] more...- Published
- 2018
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23. Muscle tone assessments for children aged 0 to 12 years: a systematic review.
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Goo, Miran, Tucker, Kylie, and Johnston, Leanne M.
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MUSCLE tone ,APRAXIA ,NEWBORN infants ,CEREBRAL palsy ,SYSTEMATIC reviews ,BRAIN injuries ,DEVELOPMENTAL disabilities ,MUSCLE diseases ,SKELETAL muscle ,DISEASE complications - Abstract
Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
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- 2018
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24. Adductor magnus: An EMG investigation into proximal and distal portions and direction specific action.
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Benn, Matthew L., Pizzari, Tania, Rath, Leanne, Tucker, Kylie, and Semciw, Adam I.
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- 2018
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25. Effect of experimental muscle pain on the acquisition and retention of locomotor adaptation: different motor strategies for a similar performance.
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Bouffard, Jason, Salomoni, Sauro E., Mercier, Catherine, Tucker, Kylie, Roy, Jean-Sébastien, van den Hoorn, Wolbert, Hodges, Paul W., and Bouyer, Laurent J.
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MYALGIA ,FOOT pain ,FOOT movements ,PAIN management ,MOTOR learning ,HYPERTONIC saline solutions ,TIBIALIS anterior - Abstract
As individuals with musculoskeletal disorders often experience motor impairments, contemporary rehabilitation relies heavily on the use of motor learning principles. However, motor impairments are often associated with pain. Although there is substantial evidence that muscle pain interferes with motor control, much less is known on its impact on motor learning. The objective of the present study was to assess the effects of muscle pain on locomotor learning. Two groups (Pain and Control) of healthy participants performed a locomotor adaptation task (robotized ankle-foot orthosis perturbing ankle movements during swing) on two consecutive days. On day 1 (acquisition), hypertonic saline was injected in the tibialis anterior (TA) muscle of the Pain group participants, while Control group participants were pain free. All participants were pain free on day 2 (retention). Changes in movement errors caused by the perturbation were assessed as an indicator of motor performance. Detailed analysis of kinematic and electromyographic data provided information about motor strategies. No between-group differences were observed on motor performance measured during the acquisition and retention phases. However, Pain group participants had a residual movement error later in the swing phase and smaller early TA activation than Control group participants, thereby suggesting a reduction in the use of anticipatory motor strategies to overcome the perturbation. Muscle pain did not interfere with global motor performance during locomotor adaptation. The different motor strategies used in the presence of muscle pain may reflect a diminished ability to anticipate the consequences of a perturbation. [ABSTRACT FROM AUTHOR] more...
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- 2018
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26. Heterogeneity of passive elastic properties within the quadriceps femoris muscle-tendon unit.
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Coombes, Brooke K., Ziegenfuss, Brandon, David, Michael, Badya, Rohitha, van den Hoorn, Wolbert, Hug, François, and Tucker, Kylie
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QUADRICEPS muscle physiology ,TENDON physiology ,ELASTICITY (Physiology) ,MUSCLE strength ,ELECTROMYOGRAPHY ,PATELLA ,PATELLAR tendon ,ELASTICITY ,MUSCLE contraction ,PHYSIOLOGY - Abstract
Purpose: The purpose of this study was to compare regional elastic properties between anterior and posterior regions of the patellar tendon, and individual quadriceps muscles, over a range of knee flexion angles.Methods: An isokinetic dynamometer passively positioned the non-dominant knee of 19 young, healthy participants, at 25°, 40°, 55°, 70° and 85° flexion. Shear wave velocity (SWV, an index of tissue elasticity) was measured using ultrasound shear wave elastography in a relaxed (passive) state, confirmed by electromyography.Results: SWV of the patellar tendon and quadriceps muscles increased with knee flexion (longer muscle-tendon unit; P < 0.001). Within the proximal third of the patellar tendon, SWV was lower in the posterior than anterior region at 70° (P = 0.002) and 85° (P < 0.001), but not at 25°, 40° or 55° (region-by-angle interaction, P = 0.007). No differences were found between anterior and posterior regions within the middle third of the patellar tendon (P = 0.332). For the quadriceps muscles, a significant muscle-by-angle (P < 0.001) interaction was also observed. SWV of VL was greater than VM at 55° (P = 0.005), 70° (P = 0.001) and 85° (P < 0.001), but not at 25° or 40°. SWV of RF was lower than VL at all angles (all P < 0.002) and lower than VM at 55°, 70° and 85° (all P < 0.002).Conclusions: Passive knee flexion at and beyond 70° was associated with non-uniform elastic properties within the proximal patellar tendon and between individual quadriceps muscles. To what extent this heterogeneity of passive elastic properties contributes to injury remains unknown. [ABSTRACT FROM AUTHOR] more...- Published
- 2018
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27. Muscle Coordination and the Development of Musculoskeletal Disorders.
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Hug, François and Tucker, Kylie
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- 2017
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28. A single-blinded, randomized, parallel group superiority trial investigating the effects of footwear and custom foot orthoses versus footwear alone in individuals with patellofemoral joint osteoarthritis: a phase II pilot trial protocol.
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Wyndow, Narelle, Crossley, Kay M., Vicenzino, Bill, Tucker, Kylie, and Collins, Natalie J.
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OSTEOARTHRITIS treatment ,CLINICAL trials ,FOOTWEAR ,FOOT orthoses ,PATELLOFEMORAL joint diseases - Abstract
Background: Patellofemoral joint osteoarthritis is a common condition, yet information regarding conservative management is lacking. Foot orthoses are an effective intervention for improving pain and function in younger individuals with patellofemoral pain and may be effective in those with patellofemoral osteoarthritis. This pilot study will seek to establish the feasibility of a phase III randomised controlled trial to investigate whether foot orthoses worn in prescribed motion controlled footwear are superior to prescribed motion control footwear alone in the management of patellofemoral osteoarthritis. Methods/design: This phase II pilot clinical trial is designed as a randomized, single-blind, parallel group, two arm, superiority trial. The trial will recruit 44 participants from Queensland and Tasmania, Australia. Volunteers aged 40 years and over must have clinical symptoms and radiographic evidence of patellofemoral osteoarthritis to be eligible for inclusion. Those eligible will be randomized to receive either foot orthoses and prescribed motion control shoes, or prescribed motion control shoes alone, to be worn for a period of 4 months. The feasibility of a phase III clinical trial will be evaluated by assessing factors such as recruitment rate, number of eligible participants, participant compliance with the study protocol, adverse events, and drop-out rate. A secondary aim of the study will be to determine completion rates and calculate effect sizes for patient reported outcome measures such as knee-related symptoms, function, quality of life, kinesiophobia, self-efficacy, general and mental health, and physical activity at 2 and 4 months. Primary outcomes will be reported descriptively while effect sizes and 95% confidence intervals will be calculated for the secondary outcome measures. Data will be analysed using an intention-to-treat principle. Discussion: The results of this pilot trial will help determine the feasibility of a phase III clinical trial investigating whether foot orthoses plus motion control footwear are superior to motion control footwear alone in individuals with patellofemoral osteoarthritis. A Phase III clinical trial will help guide footwear and foot orthoses recommendations in the clinical management of this disorder. [ABSTRACT FROM AUTHOR] more...
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- 2017
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29. Motor adaptations to local muscle pain during a bilateral cyclic task.
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Brøchner Nielsen, Niels-Peter, Tucker, Kylie, Dorel, Sylvain, Guével, Arnaud, and Hug, François
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MYALGIA ,ELECTROMYOGRAPHY ,MOTOR ability ,CYCLIC loads ,TASK performance ,DIAGNOSIS - Abstract
The aim of this study was to determine how unilateral pain, induced in two knee extensor muscles, affects muscle coordination during a bilateral pedaling task. Fifteen participants performed a 4-min pedaling task at 130 W in two conditions (Baseline and Pain). Pain was induced by injection of hypertonic saline into the vastus medialis (VM) and vastus lateralis (VL) muscles of one leg. Force applied throughout the pedaling cycle was measured using an instrumented pedal and used to calculate pedal power. Surface electromyography (EMG) was recorded bilaterally from eight muscles to assess changes in muscle activation strategies. Compared to Baseline, during the Pain condition, EMG amplitude of muscles of the painful leg (VL and VM-the painful muscles, and RF-another quadriceps muscle with no pain) was lower during the extension phase [(mean ± SD): VL: −22.5 ± 18.9%; P < 0.001; VM: −28.8 ± 19.9%; P < 0.001, RF: −20.2 ± 13.9%; P < 0.001]. Consistent with this, pedal power applied by the painful leg was also lower during the extension phase (−16.8 ± 14.2 W, P = 0.001) during Pain compared to Baseline. This decrease was compensated for by an 11.3 ± 8.1 W increase in pedal power applied by the non-painful leg during its extension phase ( P = 0.04). These results support pain adaptation theories, which suggest that when there is a clear opportunity to compensate, motor adaptations to pain occur to decrease load within the painful tissue. Although the pedaling task offered numerous possibilities for compensation, only between-leg compensations were systematically observed. This finding is discussed in relation to the mechanical and neural constraints of the pedaling task. [ABSTRACT FROM AUTHOR] more...
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- 2017
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30. Is There a Biomechanical Link Between Patellofemoral Pain and Osteoarthritis? A Narrative Review.
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Wyndow, Narelle, Collins, Natalie, Vicenzino, Bill, Tucker, Kylie, and Crossley, Kay
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FOOT physiology ,KNEE physiology ,KNEE radiography ,LEG physiology ,ANKLE physiology ,QUADRICEPS muscle physiology ,HAMSTRING muscle physiology ,HIP joint physiology ,TORSO physiology ,PATELLA ,ANTHROPOMETRY ,ARTICULAR cartilage ,BIOMECHANICS ,KINEMATICS ,KNEE diseases ,MAGNETIC resonance imaging ,MEDLINE ,MUSCLE contraction ,MUSCLE strength ,MUSCULAR atrophy ,NEUROPHYSIOLOGY ,ONLINE information services ,OSTEOARTHRITIS ,PHYSIOLOGICAL stress ,SYSTEMATIC reviews ,EVIDENCE-based medicine ,NEUROMUSCULAR system ,PLICA syndrome ,DISEASE progression ,KNEE pain ,SYMPTOMS ,PHYSIOLOGY - Abstract
The patellofemoral (PF) joint is the knee compartment most commonly affected by osteoarthritis (OA). Even mild PF OA is associated with considerable pain and functional limitations. Despite its prevalence and impact, little is understood of the etiology or structural and functional features of PF OA. The clinical symptoms of PF OA, such as anterior knee pain during stair ambulation and squatting, share many similarities with PF pain in adolescents and young adults. PF joint OA is most commonly diagnosed in people aged >40 years, many of whom report a history of PF pain. As such, there is growing evidence that PF pain and PF OA form a continuum of disease. This review explores the possible relationship between the presence of PF pain and the development of PF OA. We review the evidence for altered neuromotor control and biomechanical factors that may be associated with altered PF loading in people with PF pain and PF OA. In doing so, we highlight similarities and differences that may evolve along the continuum. By improving our understanding of the neuromotor and biomechanical links between PF pain and PF OA, we may highlight potential targets for new rehabilitation strategies. [ABSTRACT FROM AUTHOR] more...
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- 2016
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31. Reduced Maximal Force during Acute Anterior Knee Pain Is Associated with Deficits in Voluntary Muscle Activation.
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Salomoni, Sauro, Tucker, Kylie, Hug, François, McPhee, Megan, and Hodges, Paul
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KNEE pain ,MUSCLE contraction ,ISOMETRIC exercise ,SALINE injections ,ELECTROMYOGRAPHY - Abstract
Although maximal voluntary contraction (MVC) force is reduced during pain, studies using interpolated twitch show no consistent reduction of voluntary muscle drive. The present study aimed to test if the reduction in MVC force during acute experimental pain could be explained by increased activation of antagonist muscles, weak voluntary activation at baseline, or changes in force direction. Twenty-two healthy volunteers performed maximal voluntary isometric knee extensions before, during, and after the effects of hypertonic (pain) and isotonic (control) saline injections into the infrapatellar fat pad. The MVC force, voluntary activation, electromyographic (EMG) activity of agonist, antagonist, and auxiliary (hip) muscles, and pain cognition and anxiety scores were recorded. MVC force was 9.3% lower during pain than baseline (p < 0.001), but there was no systematic change in voluntary activation. Reduced MVC force during pain was variable between participants (SD: 14%), and was correlated with reduced voluntary activation (r = 0.90), baseline voluntary activation (r = − 0.62), and reduced EMG amplitude of agonist and antagonist muscles (all r > 0.52), but not with changes in force direction, pain or anxiety scores. Hence, reduced MVC force during acute pain was mainly explained by deficits in maximal voluntary drive. [ABSTRACT FROM AUTHOR] more...
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- 2016
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32. Motor Adaptations to Pain during a Bilateral Plantarflexion Task: Does the Cost of Using the Non-Painful Limb Matter?
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Hug, François, Hodges, Paul W., Carroll, Timothy J., De Martino, Enrico, Magnard, Justine, and Tucker, Kylie
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MOTOR ability ,PAIN management ,PLANTARFLEXION ,COST analysis ,EXTREMITIES (Anatomy) - Abstract
During a force-matched bilateral task, when pain is induced in one limb, a shift of load to the non-painful leg is classically observed. This study aimed to test the hypothesis that this adaptation to pain depends on the mechanical efficiency of the non-painful leg. We studied a bilateral plantarflexion task that allowed flexibility in the relative force produced with each leg, but constrained the sum of forces from both legs to match a target. We manipulated the mechanical efficiency of the non-painful leg by imposing scaling factors: 1, 0.75, or 0.25 to decrease mechanical efficiency (Decreased efficiency experiment: 18 participants); and 1, 1.33 or 4 to increase mechanical efficiency (Increased efficiency experiment: 17 participants). Participants performed multiple sets of three submaximal bilateral isometric plantarflexions with each scaling factor during two conditions (Baseline and Pain). Pain was induced by injection of hypertonic saline into the soleus. Force was equally distributed between legs during the Baseline contractions (laterality index was close to 1; Decreased efficiency experiment: 1.16±0.33; Increased efficiency experiment: 1.11±0.32), with no significant effect of Scaling factor. The laterality index was affected by Pain such that the painful leg contributed less than the non-painful leg to the total force (Decreased efficiency experiment: 0.90±0.41, P<0.001; Increased efficiency experiment: 0.75±0.32, P<0.001), regardless of the efficiency (scaling factor) of the non-painful leg. When compared to the force produced during Baseline of the corresponding scaling condition, a decrease in force produced by the painful leg was observed for all conditions, except for scaling 0.25. This decrease in force was correlated with a decrease in drive to the soleus muscle. These data highlight that regardless of the overall mechanical cost, the nervous system appears to prefer to alter force sharing between limbs such that force produced by the painful leg is reduced relative to the non-painful leg. [ABSTRACT FROM AUTHOR] more...
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- 2016
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33. The relationship of foot and ankle mobility to the frontal plane projection angle in asymptomatic adults.
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Wyndow, Narelle, De Jong, Amy, Rial, Krystal, Tucker, Kylie, Collins, Natalie, Vicenzino, Bill, Russell, Trevor, and Crossley, Kay
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FOOT ,ANKLE ,KNEE ,LEG ,RANGE of motion of joints - Abstract
Background: The frontal plane projection angle (FPPA) is frequently used as a measure of dynamic knee valgus during functional tasks, such as the single leg squat. Increased dynamic knee valgus is observed in people with knee pathologies including patellofemoral pain and anterior cruciate injury. As the foot is the primary interface with the support surface, foot and ankle mobility may affect the FPPA. This study investigated the relationship between foot and ankle mobility and the FPPA in asymptomatic adults. Methods: Thirty healthy people (aged 18-50 years) performed 5 single leg squats. Peak FPPA and FPPA excursion were determined from digital video recordings. Foot mobility was quantified as the difference in dorsal midfoot height or midfoot width, between non-weightbearing and bilateral weightbearing positions. Ankle joint dorsiflexion range was measured as the maximum distance in centimetres between the longest toe and the wall during a knee-to-wall lunge. Linear regressions with generalised estimating equations were used to examine relationships between variables. Results: Higher midfoot width mobility was associated with greater peak FPPA (β 0.90, p < 0.001, odds ratio [OR] 2.5), and FPPA excursion (β 0.67, p < 0.001, OR 1.9). Lower midfoot height mobility was associated with greater peak FPPA (β 0.37, p = 0.030, OR 1.4) and FPPA excursion (β 0.30, p = 0.020, OR 1.3). Lower ankle joint dorsiflexion was also associated with greater peak FPPA (β 0.61, p = 0.008, OR 1.8) and greater FPPA excursion (β 0.56, p < 0.001, OR 1.7). Conclusions: Foot and ankle mobility was significantly related to the FPPA during the single leg squat in healthy individuals. Specifically, higher midfoot width mobility, or lower ankle joint dorsiflexion range and midfoot height mobility, were associated with a greater FPPA. These foot mobility factors should be considered in the clinical management of knee-related disorders that are associated with a high FPPA. [ABSTRACT FROM AUTHOR] more...
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- 2016
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34. Cortical activity differs between position- and force-control knee extension tasks.
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Poortvliet, Peter, Tucker, Kylie, Finnigan, Simon, Scott, Dion, Sowman, Paul, and Hodges, Paul
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ELECTROENCEPHALOGRAPHY ,KNEE physiology ,ELECTROMYOGRAPHY ,NEURAL development ,ELECTRODES - Abstract
Neural control differs between position- and force-control tasks as evident from divergent effects of fatigue and pain. Unlike force-control tasks, position-control tasks focus on a postural goal to maintain a joint angle. Cortical involvement is suggested to be less during postural control, but whether this differs between position- and force-control paradigms remains unclear. Coherence estimates the functional communication between spatially distinct active regions within the cortex (cortico-cortical coherence; CCC) and between the cortex and muscles (corticomuscular coherence; CMC). We investigated whether cortical involvement differed between force-control and more posturally focused, position-control tasks. Seventeen adults performed position- and force-control knee extensor efforts at a submaximal load (10 % maximum voluntary contraction). Surface electromyography was recorded from the right knee extensor and flexor muscles and brain activity using electroencephalography (EEG). CCC and CMC in the beta (13-30 Hz) and gamma (30-45 Hz) frequency bands were calculated between combinations of intra- and inter-hemispheric pairs of electrodes, and between four EEG electrodes that approximated the left motor cortical area, and right knee extensor EMG, respectively. Differences in EEG power and muscle activity were also calculated. CCC was greater across distributed regions in the force-control task. Beta EEG power in the left hemisphere was higher for the position-control task. Although averaged CMC data differed between tasks, there was no task difference for individual CMC data. Muscle activity and force did not differ between tasks. The results demonstrate differential cortical contributions to control force- versus position-control tasks. This might contribute to differences in performance outcomes of these tasks that have been shown previously. [ABSTRACT FROM AUTHOR] more...
- Published
- 2015
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35. Movement Evoked Pain and Mechanical Hyperalgesia after Intramuscular Injection of Nerve Growth Factor: A Model of Sustained Elbow Pain.
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Bergin, Michael Joseph Gerard, Hirata, Rogerio, Mista, Christian, Christensen, Steffan Wittrup, Tucker, Kylie, Vicenzino, Bill, Hodges, Paul, and Graven-Nielsen, Thomas
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TENNIS elbow treatment ,NERVE growth factor ,ANALYSIS of variance ,CONFIDENCE intervals ,HYPERALGESIA ,INTRAMUSCULAR injections ,PAIRED comparisons (Mathematics) ,RESEARCH funding ,SCALE analysis (Psychology) ,STATISTICAL hypothesis testing ,STATISTICS ,T-test (Statistics) ,DATA analysis ,TASK performance ,PAIN measurement ,RANDOMIZED controlled trials ,VISUAL analog scale ,REPEATED measures design ,ALGOMETRY ,DATA analysis software ,DIARY (Literary form) ,DESCRIPTIVE statistics ,MANN Whitney U Test ,THERAPEUTICS - Abstract
Objective. Lateral epicondylalgia presents as lateral elbow pain provoked by upper limb tasks. An experimental model of elbow pain provoked by movement/ muscle contraction and maintained over several days is required to better understand the mechanisms underlying sustained elbow pain. This study investigated the time course and pain location induced by nerve growth factor (NGF) injection into a wrist extensor muscle, and whether movement and muscle contraction/stretch provoked pain. Methods. On Day 0 twenty-six painfree volunteers were injected with NGF (N513) or isotonic saline (randomized) into the extensor carpi radialis brevis (ECRB) muscle of the dominant arm. On Day 2 pain was induced in all participants by hypertonic saline injection into ECRB. A Likert scale and patientrated tennis elbow evaluation (PRTEE) was used to assess pain and functional limitation (Days 0-10). Pain intensity during contraction/stretch of ECRB, and pressure pain thresholds (PPTs) were recorded before and after injections on Days 0 and 2, and Days 4 and 10. Results. Compared with isotonic saline, NGF evoked: i) greater Likert pain ratings from 12 hours postinjection until Day 6, ii) greater PRTEE scores on Days 2 and 4, iii) greater pain during ECRB contraction/ stretch on Day 2, and iv) lower PPTs on Day 4. Conclusions. This article presents a novel experimental human pain model suitable to study the sustained effects of lateral elbow pain on sensorimotor function and to probe the mechanisms underlying persistent musculoskeletal pain. [ABSTRACT FROM AUTHOR] more...
- Published
- 2015
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36. Elastography for Muscle Biomechanics: Toward the Estimation of Individual Muscle Force.
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François Hug, Tucker, Kylie, Gennisson, Jean-Luc, Tanter, Mickaël, and Nordez, Antoine
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- 2015
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37. Muscle Force Cannot Be Directly Inferred From Muscle Activation: Illustrated by the Proposed Imbalance of Force Between the Vastus Medialis and Vastus Lateralis in People With Patellofemoral Pain.
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HUG, FRANÇOIS, HODGES, PAUL W., and TUCKER, KYLIE
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QUADRICEPS muscle physiology ,BIOMECHANICS ,ELECTROMYOGRAPHY ,MUSCLE contraction ,MUSCLE strength ,MUSCLE tone ,DIAGNOSIS of musculoskeletal system diseases ,NEUROPHYSIOLOGY ,NEUROMUSCULAR system ,PLICA syndrome ,MEDICAL equipment reliability - Abstract
* SYNOPSIS: Muscle force cannot be directly inferred from neural drive assessed using electromyography (EMG). Although the limitations associated with inferring force from EMG are well known, this has received little attention in the clinical literature. This commentary discusses these limitations within the context of the imbalance of force production between the vastus medialis (VM) and vastus lateralis (VL) muscles, which has been speculated to contribute to the development and/ or persistence of patellofemoral pain. The balance of neural drive between vasti muscles is most frequently measured with 2 approaches: (1) the onset of VM EMG relative to that of the VL, and (2) the ratio of the EMG signal amplitude of the VM and VL. Here, we demonstrate that this classical approach cannot determine whether an imbalance of force exists between the VM and VL. Considerations such as altered electromechanical delay (time between the onsets of muscle activation and patellar motion) in people with patellofemoral pain may lead to a reconsideration of the classical interpretation of the onset of VM EMG signal relative to that of the VL. Also, beyond the amplitude of the neural drive, muscle force depends on several biomechanical factors (eg, specific tension and physiological cross-sectional area). Therefore, the VL/ VM activation ratio does not provide information about the VL/VM force ratio, which is ultimately the most important information from a clinical perspective. Although the literature includes defenses for both the existence and absence of this force imbalance in people with patellofemoral pain, a reconsideration of the methods used to assess this imbalance is needed. [ABSTRACT FROM AUTHOR] more...
- Published
- 2015
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38. Deloading Tape Reduces Muscle Stress at Rest and during Contraction.
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HUG, FRANÇOIS, OUELLETTE, ADAM, VICENZINO, BILL, HODGES, PAUL W., and TUCKER, KYLIE
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- 2014
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39. Between-muscle differences in the adaptation to experimental pain.
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Hug, François, Hodges, Paul W., van den Hoorn, Wolbert, and Tucker, Kylie
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MUSCLE strength measurement ,QUADRICEPS muscle physiology ,VASTUS lateralis ,PHYSIOLOGICAL stress ,MYALGIA - Abstract
This study aimed to determine whether muscle stress (force per unit area) can be redistributed between individual heads of the quadriceps muscle when pain is induced into one of these heads. Elastography was used to measure muscle shear elastic modulus (an index of muscle stress). Electromyography (EMG) was recorded from vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF). In experiment I (n = 20), participants matched a knee extension force, and thus any reduction of stress within the painful muscle would require compensation by other muscles. In experiment II (n = 13), participants matched VL EMG amplitude and were free to vary external force such that intermuscle compensation would be unnecessary to maintain the experimental task. In experiments I and II, pain was induced by injection of hypertonic saline into VM or RF. Experiment III aimed to establish whether voluntary drive to the individual muscles could be controlled independently. Participants (n = 13) were asked to voluntarily reduce activation of VM or RF while maintaining knee extension force. During VM pain, there was no change in shear elastic modulus (experiments I and II) or EMG amplitude of VM (experiment II). In contrast, RF pain was associated with a reduction in RF elastic modulus (experiments I and II: -8 to -17%) and EMG amplitude (experiment II). Participants could voluntarily reduce EMG amplitude of RF (-26%; P = 0.003) but not VM (experiment III). These results highlight between-muscle differences in adaptation to pain that might be explained by their function (monoarticular vs. biarticular) and/or the neurophysiological constraints associated to their activation. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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40. Comparison of location, depth, quality, and intensity of experimentally induced pain in 6 low back muscles.
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Tucker, Kylie J, Fels, Matthew, Walker, Scott R, and Hodges, Paul W
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- 2014
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41. Task dependency of motor adaptations to an acute noxious stimulation.
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Hug, François, Hodges, Paul W., and Tucker, Kylie
- Subjects
TASK analysis ,DEPENDENCY (Psychology) ,MOTOR ability ,ADAPTABILITY (Personality) ,NEURAL stimulation - Abstract
This study explored motor adaptations in response to an acute noxious stimulation during three tasks that differed in the number of available degrees of freedom. Fifteen participants performed three isometric forcematched tasks (single leg knee extension, single leg squat, and bilateral leg squat) in three conditions (Control, Pain, and Washout). Pain was induced by injection of hypertonic saline into the vastus medialis muscle (VM; left leg). Supersonic shear imaging was used to measure muscle shear elastic modulus as this is considered to be an index of muscle stress. Surface electromyography (EMG) was recorded bilaterally from six muscles to assess changes in neural strategies. During tasks with fewer degrees of freedom (knee extension and single leg squat task), there was no change in VM EMG amplitude or VM shear elastic modulus. In contrast, during the bilateral leg squat, VM (-32.9 ± 15.8%; P < 0.001) and vastus lateralis (-28.7 ± 14.8%; P < 0.001) EMG amplitude decreased during Pain. This decrease in activation was associated with reduced VM shear elastic modulus (-17.6 ± 23.3%; P = 0.029) and reduced force produced by the painful leg (-10.0 ± 10.2%; P = 0.046). This work provides evidence that when an obvious solution is available to decrease stress on painful tissue, this option is selected. It confirms the fundamental assumption that motor adaptations to pain aim to alter load on painful tissue to protect for further pain and/or injury. The lack of adaptation observed during force-matched tasks with fewer degrees of freedom might be explained by the limited potential to redistribute stress or a high cost induced by such a compensation. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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42. Insight into motor adaptation to pain from between-leg compensation.
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Hug, François, Hodges, Paul, Salomoni, Sauro, and Tucker, Kylie
- Subjects
PAIN ,ELECTROMYOGRAPHY ,MYALGIA ,SKELETAL muscle injuries ,MUSCLE contraction - Abstract
Purpose: Although it appears obvious that we change movement behaviors to unload the painful region, non-systematic motor adaptations observed in simple experimental tasks with pain question this theory. We investigated the effect of unilateral pain on performance of a bilateral plantarflexion task. This experimental task clearly allowed for stress on painful tissue to be reduced by modification of load sharing between legs. Methods: Fourteen participants performed a bilateral plantarflexion at 10, 30, 50 and 70 % of their MVC during 5 conditions (Baseline, Saline-1, Washout-1, Saline-2, Washout-2). For Saline-1 and -2, either isotonic saline (Iso) or hypertonic saline (Pain) was injected into the left soleus. Results: The force produced by the painful leg was less during Pain than Baseline (range −52.6 % at 10 % of MVC to −20.1 % at 70 % of MVC; P < 0.003). This was compensated by more force produced by the non-painful leg (range 18.4 % at 70 % of MVC to 70.2 % at 10 % of MVC; P < 0.001). The reduction in plantarflexion force was not accompanied by a significant decrease in soleus electromyographic activity at 10 and 30 % of MVC. Further, no significant linear relationship was found between changes in soleus electromyographic activity and change in plantarflexion force for the painful leg (with the exception of a weak relationship at 10 % of MVC, i.e., R = 0.31). Conclusion: These results show that when the nervous system is presented with an obvious solution to decrease stress on irritated tissue, this option is selected. However, this was not strongly related to a decrease in soleus (painful muscle) activity level. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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43. Does Stress within a Muscle Change in Response to an Acute Noxious Stimulus?
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Tucker, Kylie, Hodges, Paul W., Van den Hoorn, Wolbert, Nordez, Antoine, and Hug, François
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STIMULUS & response (Biology) ,MUSCLE physiology ,SHEAR waves ,BIOMECHANICS ,COGNITIVE neuroscience ,MUSCULOSKELETAL system - Abstract
Background: Altered muscle activation during pain is thought to redistribute stress within muscles and ultimately decrease the load on painful structures. However, change in muscle stress during pain has not been directly tested. The aim of the present study is to determine whether stress within muscle tissue is reduced during local acute experimental pain. Methods and Results: Ten participants attended 2 experimental sessions that each involved isometric knee extension tasks in 2 series of control trials and 1 series of test trials at ∼10%MVC. Shear elastic modulus was measured from vastus lateralis using a shear wave elastographic technique (Supersonic Shear Imaging). Prior to the test contractions, a bolus of hypertonic (Pain) or isotonic saline (No-pain) was injected into vastus lateralis. Pain intensity was 5.2±1.0 during the painful contractions. The intra-session repeatability of the shear elastic modulus determined between control trials was good (ICC: 0.95 and 0.99; SEM: 5.1 and 9.3 kPa for No-pain and Pain, respectively). Muscle shear elastic modulus did not change systematically during Pain or No-pain contractions (all main effects and interaction P>0.14). Examination of data for individual participants showed that stress either increased or decreased. If the absolute change in modulus is considered between the control and the test trials, the change during Pain (16.2±9.5 kPa) was double that observed with No pain (7.9±5.9 kPa; P = 0.046). Conclusion: This is the first study to directly determine the change in stress within a muscle (change in shear elastic modulus) during pain. We conclude that experimental pain induced by hypertonic saline does not induce a systematic reduction in muscle stress during a single-joint isometric task. Therefore, the changes in muscle activity reported previously during similar tasks are unlikely to systematically reduce load in the painful region. Whether the individual-specific increase and decrease are physiologically relevant or purposeful requires further investigation. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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44. Does movement variability increase or decrease when a simple wrist task is performed during acute wrist extensor muscle pain?
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Bergin, Michael, Tucker, Kylie, Vicenzino, Bill, Hoorn, Wolbert, and Hodges, Paul
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WRIST extension ,RANGE of motion of joints ,PHYSIOLOGIC strain ,PAIN ,MYALGIA - Abstract
Purpose: The goal of complex tasks can be maintained despite variability in the movements of the multiple body segments involved in the task (VAR). This variability increases in acute pain and may enable the nervous system to search for less painful/injurious movement options. It is unclear whether VAR increases when pain challenges simple tasks with fewer movement options, yet maintain successful attainment of the goal. We hypothesised that during acute pain related to a simple movement: (1) the task goal would be maintained; (2) VAR would be increased; and (3) if VAR increased during pain, it would decrease over time. Methods: Movements of the right wrist/forearm were recorded with a three-dimensional motion analysis system and during a repetitive radial-ulnar deviation task between two target angle ranges (the task goal). We measured success of attaining the goal (repetitions that reached the target range and total absolute error in degrees), and variability in the motion of wrist flexion-extension and forearm pronation-supination (VAR). Fourteen healthy participants performed the task in one session before, during, and after wrist extensor muscle pain induced with hypertonic saline, and in another session without pain. Results: The task goal was maintained during acute pain. However, VAR in other motion planes either reduced (pronation-supination) or did not change (flexion-extension). Thus, variability of task elements is constrained, rather than increased, in simple tasks. Conclusions: These data suggest the nervous system adapts simple tasks with limited degrees of freedom by reduction of VAR rather than the increase observed for more complex tasks. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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45. A double-blind placebo-controlled investigation into the effects of interferential therapy on experimentally induced pain using a cross-over design.
- Author
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Beatti, Abulkhair, Tucker, Kylie, and Chipchase, Lucy S.
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HYPERTONIC saline solutions ,PAIN management ,ANALYSIS of variance ,CROSSOVER trials ,ELECTRIC stimulation ,HYPERTONIC solutions ,KNEE ,HEALTH outcome assessment ,PLACEBOS ,STATISTICAL sampling ,PAIN measurement ,VISUAL analog scale ,TREATMENT effectiveness ,REPEATED measures design ,BLIND experiment ,SEVERITY of illness index ,DATA analysis software - Abstract
Objectives To investigate the analgesic effect of interferential therapy (IFT) on experimentally induced anterior knee pain. Methods A double-blind placebo-controlled investigation was undertaken on 10 healthy subjects. Anterior knee pain was induced by an injection of hypertonic saline into the medial infrapatellar fat pad. Immediately, following the injection, subjects received 20 minutes of each of the following conditions: control, placebo IFT, 4 Hz IFT, or 100 Hz IFT, in random order on four separate days. Pain severity and the size of the painful region every 30 seconds were recorded until pain ceased. The location of the pain was recorded at 2, 7, and 12 minutes after the painful injection using a standardized figure of the knee divided into nine segments. Results There was no effect of condition on pain severity, size of painful area, maximum reported pain severity, maximum size of painful area, duration of pain, total pain severity, and the total size of the painful area (all P > 0.09). There was no interaction between time and condition on pain severity and size of painful area (P > 0.05). However, the location of pain was more dispersed at 7 minutes in the control condition (8/9 segments) compared with the placebo, 4 and 100 Hz conditions (2/9, 1/9, and 3/9 segments, respectively). Discussion This preliminary study indicates that IFT is not effective at reducing acute experimentally induced pain when the severity or size of the painful area is measured. However, IFT may be effective by limiting pain spreading from the source. Further research with a larger sample size is required. [ABSTRACT FROM AUTHOR] more...
- Published
- 2012
- Full Text
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46. Similar alteration of motor unit recruitment strategies during the anticipation and experience of pain.
- Author
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Tucker K, Larsson AK, Oknelid S, Hodges P, Tucker, Kylie, Larsson, Anna-Karin, Oknelid, Stina, and Hodges, Paul
- Published
- 2012
- Full Text
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47. Similar alteration of motor unit recruitment strategies during the anticipation and experience of pain
- Author
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Tucker, Kylie, Larsson, Anna-Karin, Oknelid, Stina, and Hodges, Paul
- Published
- 2012
- Full Text
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48. The effect of pain on training-induced plasticity of the corticomotor system
- Author
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Ingham, Damian, Tucker, Kylie J., Tsao, Henry, and Hodges, Paul W.
- Subjects
NEUROPLASTICITY ,TRAINING ,EFFERENT pathways ,TRANSCRANIAL magnetic stimulation ,CENTRAL pain ,PERFORMANCE evaluation - Abstract
Abstract: Pain is thought to interfere with training-induced plasticity of corticomotor pathways. Although this implies direct interference with plastic processes, it may be explained by compromised performance in the training task during pain. Repeated finger movements can induce plasticity and change the amplitude/direction of acceleration of finger movement evoked by transcranial magnetic stimulation (TMS). We hypothesized that if pain interferes with plasticity, acceleration of finger movement would not change when the training task was painful, despite control of training task performance. TMS was applied over the optimal scalp site to evoked index finger abduction movements in nine participants. Participants then trained finger adduction with feedback of finger acceleration for three 8-min sessions, in three conditions on separate days. Conditions: first dorsal interosseus (FDI) pain and control (no-pain), with injection of 5% and 0.9% hypertonic saline, respectively, into FDI; and remote pain (5% saline injection into infrapatellar fat pad). Peak acceleration of TMS-evoked finger movement and amplitude of motor evoked potentials (MEPs) in FDI were measured at baseline, between training sessions, and at three 5-min intervals after training ceased. Plastic change was observed (reduced TMS evoked peak finger acceleration in the abduction direction) after motor training during control and FDI pain, but not during the remote pain. There was no change in FDI MEPs in any conditions. These data do not support direct effects of nociceptive input (pain) on training-induced plasticity of corticomotor pathways. Remote pain may compromise learning due to distraction from the training task or other complex central pain processes. [Copyright &y& Elsevier] more...
- Published
- 2011
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49. Changes in motor unit recruitment strategy during pain alters force direction
- Author
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Tucker, Kylie J. and Hodges, Paul W.
- Subjects
MOTOR unit ,MOTOR neurons ,PAIN measurement ,ELECTRODES ,SALINE injections ,FORCE & energy - Abstract
Abstract: Motor unit (MU) recruitment is altered (decreased discharge rate and cessation of discharge in some units, and recruitment of new units) in force-matched contractions during pain compared to contractions performed before pain. As MU’s within a motoneurone pool have different force direction properties we hypothesised that altered MU recruitment during experimental knee pain would change the force vector (total force (F
T ): amplitude and angle) generated by the quadriceps. Force was produced at two levels during 1×60-s and 3×10-s isometric contractions of knee extensors, and recorded by two force transducers at right angles. This enabled calculation of both FE (extension force) and FT . MU recruitment was recorded from the medial and lateral vastii with four fine-wire electrodes. Pain was induced by hypertonic saline injection in the infra-patella fat pad. Nine subjects matched FE and six subjects also matched both medial and lateral forces (FT ) before and during pain. Changes in MU discharge pattern (decreased discharge rate (P <0.001), complete cessation of firing, and recruitment of new units) during pain were associated with a ∼5° change in absolute force angle. As force angle changed in both directions (left/right) for individual subjects with pain there was no change in average FT amplitude between conditions. When both medial and lateral forces were matched MU discharge rate decreased (P <0.001) with pain, but, fewer units ceased firing or were newly recruited during pain. Change in motoneurone recruitment during pain alters direction of muscle force. This may be a strategy to avoid pain or protect the painful part. [ABSTRACT FROM AUTHOR] more...- Published
- 2010
- Full Text
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50. Experimentally induced low back pain from hypertonic saline injections into lumbar interspinous ligament and erector spinae muscle
- Author
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Tsao, Henry, Tucker, Kylie J., Coppieters, Michel W., and Hodges, Paul W.
- Published
- 2010
- Full Text
- View/download PDF
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