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Augmented feedback and the dual-task paradigm during repeated submaximal lower limb loading
Saturday 18 October Papers / Journal of Science and Medicine in Sport 18S (2014) e136–e162
Award finalist 14 Clinical implementation of isometric exercise for patellar tendinopathy: Is it successful on the road? E. Rio 1,∗ , C. Purdam 2 , J. Cook 1 1 2
Monash University, Australia Australian Institute of Sport, Australia
Introduction: Isometric quadriceps loading has been shown to reduce patellar tendon pain significantly and immediately using a leg extension machine. The clinical utility of isometrics may be limited by access to gym equipment, especially for athletes who travel regularly for competition. This study aimed to investigate whether the KneeTT belt that loads the quadriceps isometrically demonstrates a reduction in patellar tendon pain for in-season athletes. Methods: Athletes with patellar tendinopathy (tennis, Australian football and badminton) were invited via team physiotherapists to participate in a four week in-season trial. Baseline data included the VISA-P and single leg decline squat (SDLS) (numerical pain rating score/10). The exercise consisted of an isometric squat using the belt anchored around a pillar and the participant’s lower legs for 5 × 45 s at the depth they could maintain with upright trunk. Instructions for the correct technique were provided with pictures and descriptions. Outcome measures were adherence during the four week period (number of days/week completing the exercise), mean weekly single leg decline squat pain, numbers of games or training sessions missed due to tendon pain and follow up VISA-P. No sham treatment was offered for comparison. Data were compared from baseline as patellar tendon pain is known to be recalcitrant and rarely resolves in the elite athlete during the season. Results: Pilot data is provided for six participants (two women, four men). The mean VISA-P at baseline was 71 and the mean baseline SDLS was 7.4/10. The exercise was completed on average 6 days out of 7 during each week. Follow-up mean SLDS decreased to 4/10. Follow up mean VISA-P improved to 85. Discussion: In a four week trial, the adherence to completing isometric exercise using the KneeTT belt was high. The VISA-P increased by mean 14 points, which represents the minimal clinically important difference. This study demonstrates that isometric exercise has good efficacy for in-season athletes and that it is possible to implement this in an environment without access to gym equipment. http://dx.doi.org/10.1016/j.jsams.2014.11.140 15 A new method for measuring dynamic proprioception G. Waddington ∗ , R. Adams, J. Han, J. Anson University of Canberra, Australia Historically two approaches have been used for assessing proprioceptive function, the threshold to detection of passive movement (TTDPM) and the joint position reproduction (JPR) method. During a TTDPM test, the body segment under investigation is passively moved in a predetermined direction. Participants are instructed to indicate as soon as they perceive the movement and direction. If the reported direction is wrong, the trial is discarded, and testing proceeds until 3–5 correct judgments are
e141
achieved. The JPR method is conducted under either passive or active conditions. A target joint position is passively or actively presented to the participant for a few seconds. The joint is returned to the start position, either actively or passively. Participants are then required to reproduce the target joint position. However, although both these methods provide some information about an individual’s proprioceptive status, both these approaches use non-functional slow speed movements that do not reflect real life movement patterns. A new methodology for assessing dynamic proprioception, active movement extent discrimination assessment (AMEDA) allows the assessment of proprioception to be undertaken using ‘real-life’ movements, at natural movement speeds with the participant in a normal weight bearing position. Participants are familiarised with the position of five movement stop positions of the limb being tested and undertake fifty test trials, in which all five positions are presented ten times, in a random order. After experiencing a stop position and returning to the start position, participants make a judgement as to the position number (1, 2, 3, 4 or 5) of each test movement. A complete test takes approximately 5 min. The different variables of the three protocols will be discussed in this presentation, as will the ecological validity, testing validity, data validity and ease of application of each technique. http://dx.doi.org/10.1016/j.jsams.2014.11.141 16 Augmented feedback and the dual-task paradigm during repeated submaximal lower limb loading A. Gupta ∗ , P. Clothier, K. Mudie University of Western Sydney, Australia Introduction: This study evaluated the effect of real-time augmented feedback during single-leg hopping to volitional exhaustion. Methods: Twenty seven recreationally active males (mean (SD) 22 (3) years of age, 179 (6) cm in height; 79 (12) kg) each performed on-the-spot, single-leg hopping to volitional exhaustion on a force plate. Hopping was performed with the aim to land on the audile tone of a metronome at 2.2 Hz. Real-time augmented feedback on the target hop height was provided using tactile feedback (elastic bands above the head of the participant) or visual feedback (horizontal line on a mirror in front of the participant) for each of two trials and no feedback in a third trial with the order of trials randomised. Derived variables were: duration of hop cycle, flight (tf ) and loading (tl ) phases, vertical height displacement during flight (zf ) and loading phases (zl ) and vertical stiffness (k). The duration of trials between conditions was compared using 1-way repeated measures ANOVA. Comparisons were made between the start and end of the hopping trials for each condition using 2-way repeated measures ANOVA. A Friedman 2-way ANOVA was performed to compare the percentage of trials between conditions that were maintained at 2.2 ± 5% Hz. Subsequent correlations were performed to determine if the effects were similar when providing tactile or visual feedback synchronously with the audible cue. Results: There was no difference in the duration of hopping trials between conditions (p = 0.26). Provision of augmented feedback resulted in maintenance of the tf (p ≥ 0.18), zf (p ≥ 0.14) and zl (p ≥ 0.13) between the start and end of the trials compared to hopping with no feedback (p < 0.01). With or without feedback there was no change in tl (p = 0.89) and k (p = 0.18) from start to end. Without feedback, 21 of 27 participants maintained >70% of total
e142
Saturday 18 October Papers / Journal of Science and Medicine in Sport 18S (2014) e136–e162
hops at 2.2 ± 5% Hz. However, this was significantly lower (p = 0.01) with tactile (13/21) and visual (15/21) feedback and demonstrates a dual-task interference effect. There was a strong correlation between tactile and visual feedback for duration of hopping cycle (Spearman’s r = 0.74, p ≤ 0.01), signifying that either type of feedback resulted in a similar magnitude of dual task interference. Discussion: Although feedback resulted in maintenance of the target hop height, participants were unable to maintain hopping pace. The provision of augmented feedback, commonly used as a motor learning strategy, may result in altering the motor task that was intended to remain constant. http://dx.doi.org/10.1016/j.jsams.2014.11.142
Real-time estimation of lower limb joint angles through inverse kinematics during walking using a scaled OpenSim model C. D.G. Lloyd 1
http://dx.doi.org/10.1016/j.jsams.2014.11.143 18 Lower limb kinematic changes during a fatiguing 60 min cycling time trial
17
Pizzolato 1,∗ ,
Discussion: Real-time IK produced estimates of the joint angles the same as those determined using the offline processing. The small variations present were due to the filtering of trajectories in the offline method that should not affect musculotendon forces estimates. This is the first software to calculate, in real-time, 3D joint angles using the OpenSim IK from an individually scaled anatomical model. This enables real-time estimation muscle and joint contact forces in real-time using our current EMG-driven neuromusculoskeletal models.
M.
Reggiani 2 ,
L.
Modenese 1 ,
1 Centre for Musculoskeletal Research, School of Allied Health Sciences, Griffith Health Institute, Griffith University, Australia 2 Department of Management and Engineering, University of Padua, Italy
Background: Real-time estimates of three-dimensional (3D) joint angles and musculotendon forces can potentially enable rapid patient evaluation and biofeedback for gait retraining. We have recently demonstrated real-time estimation of musculotendon forces using our electromyography (EMG)-driven neuromusculoskeletal models. However, this needs real-time estimation of 3D joint angles using inverse kinematics (IK) in OpenSim software, which involves many processing steps and other software. This preclude it is real-time use. Thus we aimed to (i) develop real-time OpenSim IK procedures, (ii) integrate this within our EMG-driven neuromusculoskeletal models, and (iii) compare the real-time estimation of 3D joint angles and musculotendon forces to those using offline processing. This will ensure real-time estimates are not compromised by marker drop and other specific operations that enable real-time processing. Method: Custom software was written in C++ to read 3D markers trajectories from Vicon motion capture system in real-time. The OpenSim IK algorithm and software was modified to accept these markers trajectories on a frame-by-frame basis. 3D gait data was acquired using a full body marker set (68 markers) for a single subject walking on a treadmill. A static calibration trial was used to initially scale the OpenSim model to the subject’s segmental dimensions. During the walking trials the custom software was used to produce and save the IK joint angles, while the marker trajectories were also saved for subsequent offline processing. The IK joint angles from hip, knee, and ankle determined using the real-time and offline pathways were then compared using a modified coefficient of multiple correlation (CMC), which assessed the similarity of waveforms where a value of 1 indicates maximum similarity. Results: We found similar hip, knee and ankle joint angle waveforms, for three consecutive gait cycles, with CMC’s of 1 for the hip and knee, and 0.998 for the ankle. A delay between the subject’s motion and the real-time calculation of joint angles was approximately 30 ms. The real-time estimation of musculotendon forces is currently being evaluated.
M. Sayers University of the Sunshine Coast, Australia Introduction: The predominant movement patterns in cycling are centred around ankle, knee and hip flexion/extension. Importantly, the cycling action also contains lower limb movements in the frontal (e.g. hip adduction/abduction and knee varus/valgus) and transverse planes (e.g. hip and knee internal/external rotation), with some researchers linking these non-sagittal movements to the relatively high incidence of lower limb overuse injuries in road cycling. Our earlier research has indicated increased variation in tibial rotation variability at the mid-drive phase position during sustained cycling, but the quantification of movement variability using discrete analyses may under, or overestimate the degree of variability present throughout the pedal stroke. Accordingly, the purpose of this study was to quantify the degree of pelvis and lower limb movement variability during sustained cycling using Normalised Root Mean Square (NoRMS) analyses. Methods: Ten experienced male road cyclists (age 36 ± 3.6 years, mass 79.8 ± 5.8 kg, and height 1.817 ± 0.046 m) performed a 60 min cycling test at a workload equivalent to 88% of onset of blood lactate accumulation (OBLA). Previous testing has indicated that this workload enabled the participants to maximise their work output during the 60 min. Three-dimensional kinematic data (200 Hz) were recorded using a 9 camera infra-red motion capture system for 20 pedal revolutions during the last minute of each 10 min period. Analyses focused on lower limb and pelvis kinematics, with NoRMS analyses being used from angle-angle data to quantify pedal stroke consistency. Results: Analysis of the angle-angle graphs indicated that the participants increased the amount of posterior pelvic tilt by approximately 3◦ during the latter stages of the test, which caused a corresponding 5◦ increase in hip flexion throughout the pedal stroke. The greatest changes in angle-angle data were in the transverse plane hip, knee and ankle graphs. Significant increases in NoRMS data were also found in transverse plane hip and knee axial rotations during the latter stages of the test. Discussion: Our results indicated that changes in pelvis orientation and non-sagittal hip and knee kinematics movement patterns occur during sustained cycling. The degree of transverse plane movement variability also increases at some joints during a sustained high intensity ride. Our results may help explain the high incidence of lower back and knee injury experienced by well trained and high performance cyclists. http://dx.doi.org/10.1016/j.jsams.2014.11.144
Award finalist 14 Clinical implementation of isometric exercise for patellar tendinopathy: Is it successful on the road? E. Rio 1,∗ , C. Purdam 2 , J. Cook 1 1 2
Monash University, Australia Australian Institute of Sport, Australia
Introduction: Isometric quadriceps loading has been shown to reduce patellar tendon pain significantly and immediately using a leg extension machine. The clinical utility of isometrics may be limited by access to gym equipment, especially for athletes who travel regularly for competition. This study aimed to investigate whether the KneeTT belt that loads the quadriceps isometrically demonstrates a reduction in patellar tendon pain for in-season athletes. Methods: Athletes with patellar tendinopathy (tennis, Australian football and badminton) were invited via team physiotherapists to participate in a four week in-season trial. Baseline data included the VISA-P and single leg decline squat (SDLS) (numerical pain rating score/10). The exercise consisted of an isometric squat using the belt anchored around a pillar and the participant’s lower legs for 5 × 45 s at the depth they could maintain with upright trunk. Instructions for the correct technique were provided with pictures and descriptions. Outcome measures were adherence during the four week period (number of days/week completing the exercise), mean weekly single leg decline squat pain, numbers of games or training sessions missed due to tendon pain and follow up VISA-P. No sham treatment was offered for comparison. Data were compared from baseline as patellar tendon pain is known to be recalcitrant and rarely resolves in the elite athlete during the season. Results: Pilot data is provided for six participants (two women, four men). The mean VISA-P at baseline was 71 and the mean baseline SDLS was 7.4/10. The exercise was completed on average 6 days out of 7 during each week. Follow-up mean SLDS decreased to 4/10. Follow up mean VISA-P improved to 85. Discussion: In a four week trial, the adherence to completing isometric exercise using the KneeTT belt was high. The VISA-P increased by mean 14 points, which represents the minimal clinically important difference. This study demonstrates that isometric exercise has good efficacy for in-season athletes and that it is possible to implement this in an environment without access to gym equipment. http://dx.doi.org/10.1016/j.jsams.2014.11.140 15 A new method for measuring dynamic proprioception G. Waddington ∗ , R. Adams, J. Han, J. Anson University of Canberra, Australia Historically two approaches have been used for assessing proprioceptive function, the threshold to detection of passive movement (TTDPM) and the joint position reproduction (JPR) method. During a TTDPM test, the body segment under investigation is passively moved in a predetermined direction. Participants are instructed to indicate as soon as they perceive the movement and direction. If the reported direction is wrong, the trial is discarded, and testing proceeds until 3–5 correct judgments are
e141
achieved. The JPR method is conducted under either passive or active conditions. A target joint position is passively or actively presented to the participant for a few seconds. The joint is returned to the start position, either actively or passively. Participants are then required to reproduce the target joint position. However, although both these methods provide some information about an individual’s proprioceptive status, both these approaches use non-functional slow speed movements that do not reflect real life movement patterns. A new methodology for assessing dynamic proprioception, active movement extent discrimination assessment (AMEDA) allows the assessment of proprioception to be undertaken using ‘real-life’ movements, at natural movement speeds with the participant in a normal weight bearing position. Participants are familiarised with the position of five movement stop positions of the limb being tested and undertake fifty test trials, in which all five positions are presented ten times, in a random order. After experiencing a stop position and returning to the start position, participants make a judgement as to the position number (1, 2, 3, 4 or 5) of each test movement. A complete test takes approximately 5 min. The different variables of the three protocols will be discussed in this presentation, as will the ecological validity, testing validity, data validity and ease of application of each technique. http://dx.doi.org/10.1016/j.jsams.2014.11.141 16 Augmented feedback and the dual-task paradigm during repeated submaximal lower limb loading A. Gupta ∗ , P. Clothier, K. Mudie University of Western Sydney, Australia Introduction: This study evaluated the effect of real-time augmented feedback during single-leg hopping to volitional exhaustion. Methods: Twenty seven recreationally active males (mean (SD) 22 (3) years of age, 179 (6) cm in height; 79 (12) kg) each performed on-the-spot, single-leg hopping to volitional exhaustion on a force plate. Hopping was performed with the aim to land on the audile tone of a metronome at 2.2 Hz. Real-time augmented feedback on the target hop height was provided using tactile feedback (elastic bands above the head of the participant) or visual feedback (horizontal line on a mirror in front of the participant) for each of two trials and no feedback in a third trial with the order of trials randomised. Derived variables were: duration of hop cycle, flight (tf ) and loading (tl ) phases, vertical height displacement during flight (zf ) and loading phases (zl ) and vertical stiffness (k). The duration of trials between conditions was compared using 1-way repeated measures ANOVA. Comparisons were made between the start and end of the hopping trials for each condition using 2-way repeated measures ANOVA. A Friedman 2-way ANOVA was performed to compare the percentage of trials between conditions that were maintained at 2.2 ± 5% Hz. Subsequent correlations were performed to determine if the effects were similar when providing tactile or visual feedback synchronously with the audible cue. Results: There was no difference in the duration of hopping trials between conditions (p = 0.26). Provision of augmented feedback resulted in maintenance of the tf (p ≥ 0.18), zf (p ≥ 0.14) and zl (p ≥ 0.13) between the start and end of the trials compared to hopping with no feedback (p < 0.01). With or without feedback there was no change in tl (p = 0.89) and k (p = 0.18) from start to end. Without feedback, 21 of 27 participants maintained >70% of total
e142
Saturday 18 October Papers / Journal of Science and Medicine in Sport 18S (2014) e136–e162
hops at 2.2 ± 5% Hz. However, this was significantly lower (p = 0.01) with tactile (13/21) and visual (15/21) feedback and demonstrates a dual-task interference effect. There was a strong correlation between tactile and visual feedback for duration of hopping cycle (Spearman’s r = 0.74, p ≤ 0.01), signifying that either type of feedback resulted in a similar magnitude of dual task interference. Discussion: Although feedback resulted in maintenance of the target hop height, participants were unable to maintain hopping pace. The provision of augmented feedback, commonly used as a motor learning strategy, may result in altering the motor task that was intended to remain constant. http://dx.doi.org/10.1016/j.jsams.2014.11.142
Real-time estimation of lower limb joint angles through inverse kinematics during walking using a scaled OpenSim model C. D.G. Lloyd 1
http://dx.doi.org/10.1016/j.jsams.2014.11.143 18 Lower limb kinematic changes during a fatiguing 60 min cycling time trial
17
Pizzolato 1,∗ ,
Discussion: Real-time IK produced estimates of the joint angles the same as those determined using the offline processing. The small variations present were due to the filtering of trajectories in the offline method that should not affect musculotendon forces estimates. This is the first software to calculate, in real-time, 3D joint angles using the OpenSim IK from an individually scaled anatomical model. This enables real-time estimation muscle and joint contact forces in real-time using our current EMG-driven neuromusculoskeletal models.
M.
Reggiani 2 ,
L.
Modenese 1 ,
1 Centre for Musculoskeletal Research, School of Allied Health Sciences, Griffith Health Institute, Griffith University, Australia 2 Department of Management and Engineering, University of Padua, Italy
Background: Real-time estimates of three-dimensional (3D) joint angles and musculotendon forces can potentially enable rapid patient evaluation and biofeedback for gait retraining. We have recently demonstrated real-time estimation of musculotendon forces using our electromyography (EMG)-driven neuromusculoskeletal models. However, this needs real-time estimation of 3D joint angles using inverse kinematics (IK) in OpenSim software, which involves many processing steps and other software. This preclude it is real-time use. Thus we aimed to (i) develop real-time OpenSim IK procedures, (ii) integrate this within our EMG-driven neuromusculoskeletal models, and (iii) compare the real-time estimation of 3D joint angles and musculotendon forces to those using offline processing. This will ensure real-time estimates are not compromised by marker drop and other specific operations that enable real-time processing. Method: Custom software was written in C++ to read 3D markers trajectories from Vicon motion capture system in real-time. The OpenSim IK algorithm and software was modified to accept these markers trajectories on a frame-by-frame basis. 3D gait data was acquired using a full body marker set (68 markers) for a single subject walking on a treadmill. A static calibration trial was used to initially scale the OpenSim model to the subject’s segmental dimensions. During the walking trials the custom software was used to produce and save the IK joint angles, while the marker trajectories were also saved for subsequent offline processing. The IK joint angles from hip, knee, and ankle determined using the real-time and offline pathways were then compared using a modified coefficient of multiple correlation (CMC), which assessed the similarity of waveforms where a value of 1 indicates maximum similarity. Results: We found similar hip, knee and ankle joint angle waveforms, for three consecutive gait cycles, with CMC’s of 1 for the hip and knee, and 0.998 for the ankle. A delay between the subject’s motion and the real-time calculation of joint angles was approximately 30 ms. The real-time estimation of musculotendon forces is currently being evaluated.
M. Sayers University of the Sunshine Coast, Australia Introduction: The predominant movement patterns in cycling are centred around ankle, knee and hip flexion/extension. Importantly, the cycling action also contains lower limb movements in the frontal (e.g. hip adduction/abduction and knee varus/valgus) and transverse planes (e.g. hip and knee internal/external rotation), with some researchers linking these non-sagittal movements to the relatively high incidence of lower limb overuse injuries in road cycling. Our earlier research has indicated increased variation in tibial rotation variability at the mid-drive phase position during sustained cycling, but the quantification of movement variability using discrete analyses may under, or overestimate the degree of variability present throughout the pedal stroke. Accordingly, the purpose of this study was to quantify the degree of pelvis and lower limb movement variability during sustained cycling using Normalised Root Mean Square (NoRMS) analyses. Methods: Ten experienced male road cyclists (age 36 ± 3.6 years, mass 79.8 ± 5.8 kg, and height 1.817 ± 0.046 m) performed a 60 min cycling test at a workload equivalent to 88% of onset of blood lactate accumulation (OBLA). Previous testing has indicated that this workload enabled the participants to maximise their work output during the 60 min. Three-dimensional kinematic data (200 Hz) were recorded using a 9 camera infra-red motion capture system for 20 pedal revolutions during the last minute of each 10 min period. Analyses focused on lower limb and pelvis kinematics, with NoRMS analyses being used from angle-angle data to quantify pedal stroke consistency. Results: Analysis of the angle-angle graphs indicated that the participants increased the amount of posterior pelvic tilt by approximately 3◦ during the latter stages of the test, which caused a corresponding 5◦ increase in hip flexion throughout the pedal stroke. The greatest changes in angle-angle data were in the transverse plane hip, knee and ankle graphs. Significant increases in NoRMS data were also found in transverse plane hip and knee axial rotations during the latter stages of the test. Discussion: Our results indicated that changes in pelvis orientation and non-sagittal hip and knee kinematics movement patterns occur during sustained cycling. The degree of transverse plane movement variability also increases at some joints during a sustained high intensity ride. Our results may help explain the high incidence of lower back and knee injury experienced by well trained and high performance cyclists. http://dx.doi.org/10.1016/j.jsams.2014.11.144