This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and... more This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and gender on relative thickness of quadriceps muscle and non-contractile tissue thickness (subcutaneous fat, SF, combined with perimuscular fascia). In 136 healthy males and females (aged 18-90 years n=63 aged 18-35 years; n=73 aged 65-90). Images of the anterior thigh (dominant) were taken in relaxed supine using B-mode ultrasound imaging. Thickness of muscle, SF and perimuscular fascia were measured, and percentage thickness of total anterior thigh thickness calculated. Independent t-tests compared groups. Correlation between tissue thickness and BMI was examined using Pearson’s coefficient. Muscle thickness was: 39±8mm in young males, 29±6mm in females, 25±4mm in older males and 20±5mm in females. Percentage muscle to thigh thickness was greater in young participants (p=0.001). Percentage SF and fascia was 17±6% in young and 26±8% in older males, 32±7% in young and 44±7% in older females. BMI was similar for age and correlated moderately with non-contractile tissue (r=0.54; p<0.001) and poorly with muscle (r=-0.01; p=0.93). In conclusion, this novel application of ultrasound imaging as a simple and rapid means of assessing thigh composition (relative thickness of muscle and non-contractile tissue) may help inform health status, e.g. in older people at risk of frailty and loss of mobility, and aid monitoring effects of weight loss or gain, deconditioning and exercise.
Abstract:
"Objective quantification of muscle size can aid clinical assessment when treating mus... more Abstract:
"Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh. Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and these were compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5 mm to 2.9 mm (95% confidence intervals -0.6-8.3 mm), which were not statistically different (p > 0.05) and were highly correlated (ICCs 3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r = 0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle."
Abstract:
Purpose: To examine interrater and within-session reliability of using the MyotonPRO d... more Abstract:
Purpose: To examine interrater and within-session reliability of using the MyotonPRO device for measuring non-neural tone
and mechanical properties of the rectus femoris and biceps brachii muscles in healthy young and older adults.
Methods: Forty-two healthy males were studied: n=21 aged 25.9 (SD 4.4) years and n=21 aged 72.1 (SD 4.9) years. The
MyotonPRO device applied brief, low force mechanical impulses to the muscle belly to produce damped oscillations of the
muscle at rest. Computing of the parameters was made automatically from the oscillation curve of non-neural mechanical
tone (state of intrinsic tension) measured as frequency [Hz], dynamic stiffness [N/m] and elasticity (logarithmic decrement).
Analysis: The means and standard deviations of all three parameters for each rater were calculated. Reliability was assessed
using intra-class correlation coefficients (ICCs) and Bland and Altman analysis.
Results: Excellent within-session intra-rater reliability was demonstrated by raters for both participant groups (intraclass
correlation coefficients, ICC 3,2 = 0.94-0.99). Interrater reliability was excellent for all rectus femoris parameters in the young
(ICC 3,1= 0.92-0.95) and older group (0.86-0.94). In biceps brachii, reliability was excellent in the young group (0.78-0.94) and
for elasticity in the older group (0.89) but was only classed as good for tone (0.67) and stiffness (0.68).
Conclusions: Different raters obtained acceptably similar results for all three parameters of rectus femoris in both age groups
and for biceps brachii in the young group, and for elasticity only in the older group. The findings indicate that the MyotonPRO
has potential use for objective assessment of mechanical muscle properties in clinical and research settings and that the
protocol for locating the site for testing biceps brachii in older participants could be modified to improve reliability.
Implications: The MyotonPRO device can be used reliably by different users to assess muscle parameters in healthy people
of different ages. Further studies are needed to add to the existing literature to establish Myoton technology as a valid and
reliable clinical and research tool for examining the effects of injury, disease and interventions in various muscles in clinical
conditions."
Journal of Neurological Disorders - Open Access, 2013
"Abstract
Background: Clinical assessments of muscle tone are subjective, often using the non-a... more "Abstract
Background: Clinical assessments of muscle tone are subjective, often using the non-affected side for comparison. The MyotonPRO offers portable, non-invasive, objective measurement of mechanical properties of muscles.
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied. Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels
"
Working Papers in the Health Sciences 2016; 1:15 Spring: 1-12., 2016
Objective: To determine the intra-rater reliability of a newly developed movement screening tool;... more Objective: To determine the intra-rater reliability of a newly developed movement screening tool; the ‘Movement control screen for older people in community settings’. The movement screening tool aims to identify movement control impairments which can potentially influence movement function. Method: Thirty one active female recreational golfers, aged 65-77 years, carried out three movement control tests included in the screening tool. Performance was video-recorded to enable repeated ratings. Each test was evaluated by criteria which were rated as pass or fail and ratings were carried out three weeks apart to examine intra-rater reliability. Reliability was assessed using percentage agreement and Cohen’s Kappa. Results: Percentage agreement for each test ranged from 93.0-97.3%, with an overall mean agreement of 95.5%. Kappa values for test scores ranged from 0.35-0.90. Percentage agreement for individual criteria ranged from 83.0-100.0%, with kappa values ranging from 0.00-1.00. Discussion: Acceptable intra-rater reliability was established for overall tests scores of the screening tool but certain criteria were identified as being less reliable than others. Recommendations are made for refinement of some criteria to improve reliability of the screening tool.
""Background: The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle me... more ""Background: The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mechanical properties (e.g. tone) and its reliability has yet to be established. Little is known about between-limb symmetry of mechanical properties in healthy older people, despite symmetry often being used as a measure of unilateral abnormalities in clinical assessment. Since quadriceps is important for mobility, it was selected for the present study.
Aims: To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods: Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results: Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and nondominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions: High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.""
This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and... more This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and gender on relative thickness of quadriceps muscle and non-contractile tissue thickness (subcutaneous fat, SF, combined with perimuscular fascia). In 136 healthy males and females (aged 18-90 years n=63 aged 18-35 years; n=73 aged 65-90). Images of the anterior thigh (dominant) were taken in relaxed supine using B-mode ultrasound imaging. Thickness of muscle, SF and perimuscular fascia were measured, and percentage thickness of total anterior thigh thickness calculated. Independent t-tests compared groups. Correlation between tissue thickness and BMI was examined using Pearson’s coefficient. Muscle thickness was: 39±8mm in young males, 29±6mm in females, 25±4mm in older males and 20±5mm in females. Percentage muscle to thigh thickness was greater in young participants (p=0.001). Percentage SF and fascia was 17±6% in young and 26±8% in older males, 32±7% in young and 44±7% in older females. BMI was similar for age and correlated moderately with non-contractile tissue (r=0.54; p<0.001) and poorly with muscle (r=-0.01; p=0.93). In conclusion, this novel application of ultrasound imaging as a simple and rapid means of assessing thigh composition (relative thickness of muscle and non-contractile tissue) may help inform health status, e.g. in older people at risk of frailty and loss of mobility, and aid monitoring effects of weight loss or gain, deconditioning and exercise.
Background: Muscle strength is widely used as an outcome measure in rehabilitation and knee exten... more Background: Muscle strength is widely used as an outcome measure in rehabilitation and knee extensor strength is an important determinant of physical function. Hand held dynamometry (HHD) is portable and easy to use; however, reliability of HHD measurements is significantly influenced by the
strength of the tester. The present study assessed the agreement between an adapted HHD and Biodex dynamometry while measuring knee extensor strength in young adults.
Method: Thirty participants aged 22–35 years (mean age 24.4 years; SD ± 2.5) were studied. Peak isometric knee extensor strength of the dominant leg was measured using the Biodex dynamometer and adapted HHD. The agreement between the maximum voluntary contractions (MVC) was analysed using Pearson’s Correlation Coefficient, intraclass correlation (ICC) and Bland–Altman analysis.
Results: The mean peak knee extensor MVC was 191.7 Nm (± 53.6) for the Biodex dynamometer and 167.5 Nm (± 55) for the adapted HHD. The mean difference in peak knee extensor strength measured using the adapted HHD was 24.1 Nm (± 30.3) lower when compared to the Biodex. However, there was good correlation between the two measures (r=0.796, ICC (3, 1): peak torque=0.796; average of three trials=0.808) and Bland–Altman plots confirmed good agreement.
Conclusions: The knee strength measurements were not influenced by examiner strength and results obtained using the adapted HDD were comparable to that using the Biodex; however, the absolute knee extensor strength obtained using the adapted HHD was generally lower.
Abstract
Objective quantification of muscle size can aid clinical assessment when treating muscu... more Abstract
Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
Objective
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh.Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and correlation using intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5mm to 2.9mm (95% confidence intervals -0.6 to 8.3mm), which were not statistically different (p>0.05) and were highly correlated (ICCs3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r=0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle.
Objective: To investigate the association between muscle strength, biomechanical functional momen... more Objective: To investigate the association between muscle strength, biomechanical functional moments during everyday tasks and health-related quality of life (HRQoL) in older adults.
Methods: Eighty-four healthy adults aged 60-88 years were tested. A torque dynamometer was utilised to measure muscle moments at the knee and hip joints. Functional assessment involved 3-D biomechanical analysis of gait, chair rise and sit-down, stair ascent and descent using an 8-camera VICON® system with Kistler force plates. HRQoL was assessed using the Short Form- 36 (SF-36) questionnaire.
Results: Spearman’s correlation coefficient showed significant correlation (p<0.001) between isometric strength and functional moments (r=0.24 to 0.67). Muscle strength was significantly correlated with SF-36 scores, including physical functioning, bodily pain, vitality, social functioning and role emotional scores. Knee flexion moment was correlated with role physical, vitality, social functioning, role emotional, mental health and mental component scores (r=0.24 to 0.40).
Conclusion: Loss of muscle strength is associated with poorer functional ability and both are associated with reduced HRQoL. The reduction of HRQoL is considerable in the physical functioning domain. Cause and effect was not established but studies need to be undertaken to evaluate the benefits of strength training, functional activity training or increased participation in life.
Strength of lower extremity muscles is an important determinant of mobility-based functional acti... more Strength of lower extremity muscles is an important determinant of mobility-based functional activities. Loss of strength with age produces functional limitation in activities of daily living such as rising from a chair or stair negotiation. However, there is limited information on the effect of age-related changes on the torque-producing ability of muscles through their ranges of joint motion. To investigate the effect of ageing on the torque-producing ability of lower extremity muscles in a large sample of older adults in three age groups. Eighty-two volunteers participated in this study and were divided into six groups according to their chronological age (60s, 70s and 80s and above) and gender (male, female). Isometric muscle strength was measured at the knee and hip joints at three positions through the joint range using a custom-built strain gauge torque dynamometer and a purpose built plinth. The peak torque of major muscle groups of the knee and hip joints decreased with increasing age at all the three joint positions at which strength was tested. The 80-year-olds had 20% lower strength compared to the 60-year-olds. Age-related decrease in muscle strength was significant when comparing 80-year-olds with the 60-year-olds (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). Strength loss was noted to be higher at the inner (muscle is shortened from mid-position) and outer (muscle is lengthened from mid-position) ranges of muscle action when compared with the mid-range position (mid-position). Gender-based differences were significant for all the strength tests (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). Strength decreased with increasing age at all the positions within joint range of motion for knee and hip joints. However, the percentage loss of muscle strength was different at different positions in the joint range. Our findings suggest that muscle strength was more preserved in the middle range of muscle function compared to the inner and outer range of muscle action. In older people, lower extremity muscles might be required to produce higher moments in joint positions that are not within the optimum mid-position for muscle action.
Background and aims: Muscle strength may decline with age differentially in the upper and lower l... more Background and aims: Muscle strength may decline with age differentially in the upper and lower limbs. This information is difficult to capture through a single measure. The present study therefore aimed to characterize the relative changes in handgrip and lower limb muscle strength with aging by expressing them as a ratio.
Methods: thirty-eight healthy volunteers aged 20–82 years performed maximal voluntary contractions (MVC) of quadriceps and handgrip using a custom-built transducer and a Jamar dynamometer respectively.
Results: the grip-quadriceps ratios for young adults was similar in males and females (0.75); indicating knee extensor force exceeded grip force by approximately 25%. Ratios were increased in older adults (p=0.05), and strength of the two muscle groups was approximately equal (1.1). Pearson’s correlation coefficients for grip against quadriceps strength were r=0.63 (young males), r=0.83 (young females), r=0.35 (older males) and r=0.05 (older females).
Conclusions: the ratio used demonstrated clear differences between the age groups. The reduced muscle strength with increasing age was expected but the higher grip/quadriceps strength ratios quantify a greater loss of quadriceps than grip strength with aging. It remains to be investigated whether the relatively greater rate of decline in quadriceps strength seen in healthy older people is more exaggerated in those who are frail, which would have implications for using grip strength as a physical marker of lower limb strength and function in those at risk of immobility and falls.
Volume 39, Issue 3, March 2014, Pages 841–846, Mar 2014
Background
Turning around is a common activity of daily living. The location of a target may be ... more Background
Turning around is a common activity of daily living. The location of a target may be known or unknown while angle and direction may vary prior to turning. A stroke can compromise coordination of body movement during turning.
Objectives
To investigate the effect of target predictability, turn angle and turn direction on the kinematic sequence of rotation of body segments in people with stroke and healthy controls when turning on-the-spot.
Methods
Ten people with stroke (age: 66 ± 10 years; 8 males) and 10 age-matched controls (age: 65 ± 8 years; 6 males) were asked to either turn to a specific light (predictable condition) or locate and turn to a random light (unpredictable condition) placed at 45°, 90° or 135° to the right or left when a light in front extinguished.
Results
People with stroke initiated movement of the segments significantly later than the controls (p = 0.014). The sequence of onset of rotation of the segments was not different between both groups. Target predictability affected the sequence of the segments; the eyes, head and shoulder started moving simultaneously when turning to unpredictable targets while the head and shoulder started moving before the eyes when turning to predictable targets. The sequence was also different across the three turn angles for each predictability condition. However, the sequence remained the same when turning to both sides in each group.
Conclusion
Similarities between the groups may be because the time since the stroke was long and therefore some recovery of function may have occurred. Slowness of movement in people with stroke may predispose them to falls.
Background
The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mech... more Background
The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mechanical properties (e.g. tone) and its reliability has yet to be established. Little is known about between-limb symmetry of mechanical properties in healthy older people, despite symmetry often being used as a measure of unilateral abnormalities in clinical assessment. Since quadriceps is important for mobility, it was selected for the present study.
Aims
To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods
Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results
Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and non-dominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions
High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.
Age-related decline in physical capacity and diminishing physiological reserves may increase the ... more Age-related decline in physical capacity and diminishing physiological reserves may increase the demand placed on lower extremity joints during everyday activities. This study aimed to characterise the functional demand at the knee and hip joints of older adults during various mobility activities. Eighty-four healthy participants (60-88 years) performed strength tests using a custom-built dynamometer. Biomechanical assessment of gait, chair rise and sit-down, stair ascent and descent was performed using an 8-camera VICON system (120Hz) and Kistler force plates. Comparisons between groups (60’s, 70’s, and 80’s) were made using ANOVA.The functional demand (FD) was defined as the muscle moment generated during a task, divided by the maximum isometric strength (expressed as a percentage). FD was higher in the 80’s age group compared to those in the 60’s. The demand on hip and knee extensors was normally higher than those of flexors across all the activities. The knee extensor demand during gait (101%), stair ascent (103%) and stair descent (120%); and hip extensor demand during gait (127%) were high requiring moments in excess of the maximum isometric strength available at these joints. FD during chair rise and sit-down were comparatively lower with knee extensor demands of 73% and 69% and hip extensor demands of 88% and 51% respectively. Gait, stair ascent and descent placed high demands on the knee extensors while hip extensor demand was high for gait, chair rise, sit-down and stair ascent. The levels of demand leave little reserve capacity for the older adult to draw on in unexpected circumstances.
Background: Sniff nasal inspiratory pressure (SNIP) and peak oral inspiratory flow (PIF) are port... more Background: Sniff nasal inspiratory pressure (SNIP) and peak oral inspiratory flow (PIF) are portable, relatively new methods for indirect measurement of respiratory muscle strength. The reliability and acceptability of these measures were investigated in older adults.
Methods: Twenty one self-reported healthy adults, aged 65-84 years (Mean 73.5; SD 6.4 years). Participants were tested in a sitting position on two occasions, one week apart. The best of three attempts for PIF measured through the mouth, and five for each nostril for SNIP were recorded. Reliability was tested using intra-class correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC) and Bland and Altman analysis. Feedback on the measures in relation to ease of completion and preference was obtained using a semi-structured interview.
Results: Between-day reliability of SNIP and PIF were ICC3,1 0.76 (95% CI 0.49-0.9) and 0.92 (0.81-0.97) respectively. Standard error of measurement for SNIP (11.94 cmH2O) and MDC (33.10 cmH2O) were at the least 61% higher than for PIF. The participants reported difficulties in performing SNIP, rating it as being less easy and uncomfortable to perform than PIF, with a higher rate of missing data for SNIP due to participants’ dislike of test.
Conclusions: The wide range of SNIP readings, lower ICC value and negative user feedback is suggestive of a less robust and unacceptable clinical measure. PIF showed excellent reliability and acceptability and is therefore recommended for assessing inspiratory muscle strength in older people without known obstructive lung disease.
"
"Background: Clinical assessments of muscle tone are subjective, often using the non-affected sid... more "Background: Clinical assessments of muscle tone are subjective, often using the non-affected side for comparison. The MyotonPRO offers portable, non-invasive, objective measurement of mechanical properties of muscles.
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied.
Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels.
This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and... more This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and gender on relative thickness of quadriceps muscle and non-contractile tissue thickness (subcutaneous fat, SF, combined with perimuscular fascia). In 136 healthy males and females (aged 18-90 years n=63 aged 18-35 years; n=73 aged 65-90). Images of the anterior thigh (dominant) were taken in relaxed supine using B-mode ultrasound imaging. Thickness of muscle, SF and perimuscular fascia were measured, and percentage thickness of total anterior thigh thickness calculated. Independent t-tests compared groups. Correlation between tissue thickness and BMI was examined using Pearson’s coefficient. Muscle thickness was: 39±8mm in young males, 29±6mm in females, 25±4mm in older males and 20±5mm in females. Percentage muscle to thigh thickness was greater in young participants (p=0.001). Percentage SF and fascia was 17±6% in young and 26±8% in older males, 32±7% in young and 44±7% in older females. BMI was similar for age and correlated moderately with non-contractile tissue (r=0.54; p<0.001) and poorly with muscle (r=-0.01; p=0.93). In conclusion, this novel application of ultrasound imaging as a simple and rapid means of assessing thigh composition (relative thickness of muscle and non-contractile tissue) may help inform health status, e.g. in older people at risk of frailty and loss of mobility, and aid monitoring effects of weight loss or gain, deconditioning and exercise.
Abstract:
"Objective quantification of muscle size can aid clinical assessment when treating mus... more Abstract:
"Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh. Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and these were compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5 mm to 2.9 mm (95% confidence intervals -0.6-8.3 mm), which were not statistically different (p > 0.05) and were highly correlated (ICCs 3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r = 0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle."
Abstract:
Purpose: To examine interrater and within-session reliability of using the MyotonPRO d... more Abstract:
Purpose: To examine interrater and within-session reliability of using the MyotonPRO device for measuring non-neural tone
and mechanical properties of the rectus femoris and biceps brachii muscles in healthy young and older adults.
Methods: Forty-two healthy males were studied: n=21 aged 25.9 (SD 4.4) years and n=21 aged 72.1 (SD 4.9) years. The
MyotonPRO device applied brief, low force mechanical impulses to the muscle belly to produce damped oscillations of the
muscle at rest. Computing of the parameters was made automatically from the oscillation curve of non-neural mechanical
tone (state of intrinsic tension) measured as frequency [Hz], dynamic stiffness [N/m] and elasticity (logarithmic decrement).
Analysis: The means and standard deviations of all three parameters for each rater were calculated. Reliability was assessed
using intra-class correlation coefficients (ICCs) and Bland and Altman analysis.
Results: Excellent within-session intra-rater reliability was demonstrated by raters for both participant groups (intraclass
correlation coefficients, ICC 3,2 = 0.94-0.99). Interrater reliability was excellent for all rectus femoris parameters in the young
(ICC 3,1= 0.92-0.95) and older group (0.86-0.94). In biceps brachii, reliability was excellent in the young group (0.78-0.94) and
for elasticity in the older group (0.89) but was only classed as good for tone (0.67) and stiffness (0.68).
Conclusions: Different raters obtained acceptably similar results for all three parameters of rectus femoris in both age groups
and for biceps brachii in the young group, and for elasticity only in the older group. The findings indicate that the MyotonPRO
has potential use for objective assessment of mechanical muscle properties in clinical and research settings and that the
protocol for locating the site for testing biceps brachii in older participants could be modified to improve reliability.
Implications: The MyotonPRO device can be used reliably by different users to assess muscle parameters in healthy people
of different ages. Further studies are needed to add to the existing literature to establish Myoton technology as a valid and
reliable clinical and research tool for examining the effects of injury, disease and interventions in various muscles in clinical
conditions."
Journal of Neurological Disorders - Open Access, 2013
"Abstract
Background: Clinical assessments of muscle tone are subjective, often using the non-a... more "Abstract
Background: Clinical assessments of muscle tone are subjective, often using the non-affected side for comparison. The MyotonPRO offers portable, non-invasive, objective measurement of mechanical properties of muscles.
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied. Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels
"
Working Papers in the Health Sciences 2016; 1:15 Spring: 1-12., 2016
Objective: To determine the intra-rater reliability of a newly developed movement screening tool;... more Objective: To determine the intra-rater reliability of a newly developed movement screening tool; the ‘Movement control screen for older people in community settings’. The movement screening tool aims to identify movement control impairments which can potentially influence movement function. Method: Thirty one active female recreational golfers, aged 65-77 years, carried out three movement control tests included in the screening tool. Performance was video-recorded to enable repeated ratings. Each test was evaluated by criteria which were rated as pass or fail and ratings were carried out three weeks apart to examine intra-rater reliability. Reliability was assessed using percentage agreement and Cohen’s Kappa. Results: Percentage agreement for each test ranged from 93.0-97.3%, with an overall mean agreement of 95.5%. Kappa values for test scores ranged from 0.35-0.90. Percentage agreement for individual criteria ranged from 83.0-100.0%, with kappa values ranging from 0.00-1.00. Discussion: Acceptable intra-rater reliability was established for overall tests scores of the screening tool but certain criteria were identified as being less reliable than others. Recommendations are made for refinement of some criteria to improve reliability of the screening tool.
""Background: The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle me... more ""Background: The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mechanical properties (e.g. tone) and its reliability has yet to be established. Little is known about between-limb symmetry of mechanical properties in healthy older people, despite symmetry often being used as a measure of unilateral abnormalities in clinical assessment. Since quadriceps is important for mobility, it was selected for the present study.
Aims: To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods: Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results: Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and nondominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions: High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.""
This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and... more This study aimed to use ultrasound imaging to provide objective data on the effects of ageing and gender on relative thickness of quadriceps muscle and non-contractile tissue thickness (subcutaneous fat, SF, combined with perimuscular fascia). In 136 healthy males and females (aged 18-90 years n=63 aged 18-35 years; n=73 aged 65-90). Images of the anterior thigh (dominant) were taken in relaxed supine using B-mode ultrasound imaging. Thickness of muscle, SF and perimuscular fascia were measured, and percentage thickness of total anterior thigh thickness calculated. Independent t-tests compared groups. Correlation between tissue thickness and BMI was examined using Pearson’s coefficient. Muscle thickness was: 39±8mm in young males, 29±6mm in females, 25±4mm in older males and 20±5mm in females. Percentage muscle to thigh thickness was greater in young participants (p=0.001). Percentage SF and fascia was 17±6% in young and 26±8% in older males, 32±7% in young and 44±7% in older females. BMI was similar for age and correlated moderately with non-contractile tissue (r=0.54; p<0.001) and poorly with muscle (r=-0.01; p=0.93). In conclusion, this novel application of ultrasound imaging as a simple and rapid means of assessing thigh composition (relative thickness of muscle and non-contractile tissue) may help inform health status, e.g. in older people at risk of frailty and loss of mobility, and aid monitoring effects of weight loss or gain, deconditioning and exercise.
Background: Muscle strength is widely used as an outcome measure in rehabilitation and knee exten... more Background: Muscle strength is widely used as an outcome measure in rehabilitation and knee extensor strength is an important determinant of physical function. Hand held dynamometry (HHD) is portable and easy to use; however, reliability of HHD measurements is significantly influenced by the
strength of the tester. The present study assessed the agreement between an adapted HHD and Biodex dynamometry while measuring knee extensor strength in young adults.
Method: Thirty participants aged 22–35 years (mean age 24.4 years; SD ± 2.5) were studied. Peak isometric knee extensor strength of the dominant leg was measured using the Biodex dynamometer and adapted HHD. The agreement between the maximum voluntary contractions (MVC) was analysed using Pearson’s Correlation Coefficient, intraclass correlation (ICC) and Bland–Altman analysis.
Results: The mean peak knee extensor MVC was 191.7 Nm (± 53.6) for the Biodex dynamometer and 167.5 Nm (± 55) for the adapted HHD. The mean difference in peak knee extensor strength measured using the adapted HHD was 24.1 Nm (± 30.3) lower when compared to the Biodex. However, there was good correlation between the two measures (r=0.796, ICC (3, 1): peak torque=0.796; average of three trials=0.808) and Bland–Altman plots confirmed good agreement.
Conclusions: The knee strength measurements were not influenced by examiner strength and results obtained using the adapted HDD were comparable to that using the Biodex; however, the absolute knee extensor strength obtained using the adapted HHD was generally lower.
Abstract
Objective quantification of muscle size can aid clinical assessment when treating muscu... more Abstract
Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
Objective
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh.Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and correlation using intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5mm to 2.9mm (95% confidence intervals -0.6 to 8.3mm), which were not statistically different (p>0.05) and were highly correlated (ICCs3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r=0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle.
Objective: To investigate the association between muscle strength, biomechanical functional momen... more Objective: To investigate the association between muscle strength, biomechanical functional moments during everyday tasks and health-related quality of life (HRQoL) in older adults.
Methods: Eighty-four healthy adults aged 60-88 years were tested. A torque dynamometer was utilised to measure muscle moments at the knee and hip joints. Functional assessment involved 3-D biomechanical analysis of gait, chair rise and sit-down, stair ascent and descent using an 8-camera VICON® system with Kistler force plates. HRQoL was assessed using the Short Form- 36 (SF-36) questionnaire.
Results: Spearman’s correlation coefficient showed significant correlation (p<0.001) between isometric strength and functional moments (r=0.24 to 0.67). Muscle strength was significantly correlated with SF-36 scores, including physical functioning, bodily pain, vitality, social functioning and role emotional scores. Knee flexion moment was correlated with role physical, vitality, social functioning, role emotional, mental health and mental component scores (r=0.24 to 0.40).
Conclusion: Loss of muscle strength is associated with poorer functional ability and both are associated with reduced HRQoL. The reduction of HRQoL is considerable in the physical functioning domain. Cause and effect was not established but studies need to be undertaken to evaluate the benefits of strength training, functional activity training or increased participation in life.
Strength of lower extremity muscles is an important determinant of mobility-based functional acti... more Strength of lower extremity muscles is an important determinant of mobility-based functional activities. Loss of strength with age produces functional limitation in activities of daily living such as rising from a chair or stair negotiation. However, there is limited information on the effect of age-related changes on the torque-producing ability of muscles through their ranges of joint motion. To investigate the effect of ageing on the torque-producing ability of lower extremity muscles in a large sample of older adults in three age groups. Eighty-two volunteers participated in this study and were divided into six groups according to their chronological age (60s, 70s and 80s and above) and gender (male, female). Isometric muscle strength was measured at the knee and hip joints at three positions through the joint range using a custom-built strain gauge torque dynamometer and a purpose built plinth. The peak torque of major muscle groups of the knee and hip joints decreased with increasing age at all the three joint positions at which strength was tested. The 80-year-olds had 20% lower strength compared to the 60-year-olds. Age-related decrease in muscle strength was significant when comparing 80-year-olds with the 60-year-olds (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). Strength loss was noted to be higher at the inner (muscle is shortened from mid-position) and outer (muscle is lengthened from mid-position) ranges of muscle action when compared with the mid-range position (mid-position). Gender-based differences were significant for all the strength tests (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). Strength decreased with increasing age at all the positions within joint range of motion for knee and hip joints. However, the percentage loss of muscle strength was different at different positions in the joint range. Our findings suggest that muscle strength was more preserved in the middle range of muscle function compared to the inner and outer range of muscle action. In older people, lower extremity muscles might be required to produce higher moments in joint positions that are not within the optimum mid-position for muscle action.
Background and aims: Muscle strength may decline with age differentially in the upper and lower l... more Background and aims: Muscle strength may decline with age differentially in the upper and lower limbs. This information is difficult to capture through a single measure. The present study therefore aimed to characterize the relative changes in handgrip and lower limb muscle strength with aging by expressing them as a ratio.
Methods: thirty-eight healthy volunteers aged 20–82 years performed maximal voluntary contractions (MVC) of quadriceps and handgrip using a custom-built transducer and a Jamar dynamometer respectively.
Results: the grip-quadriceps ratios for young adults was similar in males and females (0.75); indicating knee extensor force exceeded grip force by approximately 25%. Ratios were increased in older adults (p=0.05), and strength of the two muscle groups was approximately equal (1.1). Pearson’s correlation coefficients for grip against quadriceps strength were r=0.63 (young males), r=0.83 (young females), r=0.35 (older males) and r=0.05 (older females).
Conclusions: the ratio used demonstrated clear differences between the age groups. The reduced muscle strength with increasing age was expected but the higher grip/quadriceps strength ratios quantify a greater loss of quadriceps than grip strength with aging. It remains to be investigated whether the relatively greater rate of decline in quadriceps strength seen in healthy older people is more exaggerated in those who are frail, which would have implications for using grip strength as a physical marker of lower limb strength and function in those at risk of immobility and falls.
Volume 39, Issue 3, March 2014, Pages 841–846, Mar 2014
Background
Turning around is a common activity of daily living. The location of a target may be ... more Background
Turning around is a common activity of daily living. The location of a target may be known or unknown while angle and direction may vary prior to turning. A stroke can compromise coordination of body movement during turning.
Objectives
To investigate the effect of target predictability, turn angle and turn direction on the kinematic sequence of rotation of body segments in people with stroke and healthy controls when turning on-the-spot.
Methods
Ten people with stroke (age: 66 ± 10 years; 8 males) and 10 age-matched controls (age: 65 ± 8 years; 6 males) were asked to either turn to a specific light (predictable condition) or locate and turn to a random light (unpredictable condition) placed at 45°, 90° or 135° to the right or left when a light in front extinguished.
Results
People with stroke initiated movement of the segments significantly later than the controls (p = 0.014). The sequence of onset of rotation of the segments was not different between both groups. Target predictability affected the sequence of the segments; the eyes, head and shoulder started moving simultaneously when turning to unpredictable targets while the head and shoulder started moving before the eyes when turning to predictable targets. The sequence was also different across the three turn angles for each predictability condition. However, the sequence remained the same when turning to both sides in each group.
Conclusion
Similarities between the groups may be because the time since the stroke was long and therefore some recovery of function may have occurred. Slowness of movement in people with stroke may predispose them to falls.
Background
The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mech... more Background
The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mechanical properties (e.g. tone) and its reliability has yet to be established. Little is known about between-limb symmetry of mechanical properties in healthy older people, despite symmetry often being used as a measure of unilateral abnormalities in clinical assessment. Since quadriceps is important for mobility, it was selected for the present study.
Aims
To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods
Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results
Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and non-dominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions
High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.
Age-related decline in physical capacity and diminishing physiological reserves may increase the ... more Age-related decline in physical capacity and diminishing physiological reserves may increase the demand placed on lower extremity joints during everyday activities. This study aimed to characterise the functional demand at the knee and hip joints of older adults during various mobility activities. Eighty-four healthy participants (60-88 years) performed strength tests using a custom-built dynamometer. Biomechanical assessment of gait, chair rise and sit-down, stair ascent and descent was performed using an 8-camera VICON system (120Hz) and Kistler force plates. Comparisons between groups (60’s, 70’s, and 80’s) were made using ANOVA.The functional demand (FD) was defined as the muscle moment generated during a task, divided by the maximum isometric strength (expressed as a percentage). FD was higher in the 80’s age group compared to those in the 60’s. The demand on hip and knee extensors was normally higher than those of flexors across all the activities. The knee extensor demand during gait (101%), stair ascent (103%) and stair descent (120%); and hip extensor demand during gait (127%) were high requiring moments in excess of the maximum isometric strength available at these joints. FD during chair rise and sit-down were comparatively lower with knee extensor demands of 73% and 69% and hip extensor demands of 88% and 51% respectively. Gait, stair ascent and descent placed high demands on the knee extensors while hip extensor demand was high for gait, chair rise, sit-down and stair ascent. The levels of demand leave little reserve capacity for the older adult to draw on in unexpected circumstances.
Background: Sniff nasal inspiratory pressure (SNIP) and peak oral inspiratory flow (PIF) are port... more Background: Sniff nasal inspiratory pressure (SNIP) and peak oral inspiratory flow (PIF) are portable, relatively new methods for indirect measurement of respiratory muscle strength. The reliability and acceptability of these measures were investigated in older adults.
Methods: Twenty one self-reported healthy adults, aged 65-84 years (Mean 73.5; SD 6.4 years). Participants were tested in a sitting position on two occasions, one week apart. The best of three attempts for PIF measured through the mouth, and five for each nostril for SNIP were recorded. Reliability was tested using intra-class correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC) and Bland and Altman analysis. Feedback on the measures in relation to ease of completion and preference was obtained using a semi-structured interview.
Results: Between-day reliability of SNIP and PIF were ICC3,1 0.76 (95% CI 0.49-0.9) and 0.92 (0.81-0.97) respectively. Standard error of measurement for SNIP (11.94 cmH2O) and MDC (33.10 cmH2O) were at the least 61% higher than for PIF. The participants reported difficulties in performing SNIP, rating it as being less easy and uncomfortable to perform than PIF, with a higher rate of missing data for SNIP due to participants’ dislike of test.
Conclusions: The wide range of SNIP readings, lower ICC value and negative user feedback is suggestive of a less robust and unacceptable clinical measure. PIF showed excellent reliability and acceptability and is therefore recommended for assessing inspiratory muscle strength in older people without known obstructive lung disease.
"
"Background: Clinical assessments of muscle tone are subjective, often using the non-affected sid... more "Background: Clinical assessments of muscle tone are subjective, often using the non-affected side for comparison. The MyotonPRO offers portable, non-invasive, objective measurement of mechanical properties of muscles.
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied.
Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels.
Rapid and unprecedented population ageing poses a serious social and economic challenge across th... more Rapid and unprecedented population ageing poses a serious social and economic challenge across the developed world. Shifts in dependency ratios point to escalating welfare and pensions costs which require radical and imaginative responses from Government and industry. The key to this is maintaining a healthy population that is able and willing to work longer before retirement and can remain independent for as long as possible afterwards as well as bringing disabled people into mainstream life and employment. ontributions focus on the following topics. This chapter focuses on design issues for a more inclusive world, explaining InclusiveCA as a software resource for designers involved in the development and evaluation of truly usable and accessible systems for users with special needs.
International Society for Posture and Gait Research/ Gait and Mental Function 1st joint World Congress, 2012
"Background and Aim:
Turning around to interact with the environment is a common activity of dai... more "Background and Aim:
Turning around to interact with the environment is a common activity of daily living. The location of a target for interaction may be known or unknown prior to turning and the angle of a turn may vary depending on the task to be carried out. A stroke can compromise coordination of body movement during turning] which may pose a risk for instability and subsequent falls. The aim of this study was to investigate the kinematic sequence of rotation of body segments in people with stroke and healthy controls when turning on the spot to predictable and unpredictable targets placed at three different angles (45°, 90° and 135°).
Methods:
Nine people with stroke [age: 64±9 (mean±SD) years] and nine healthy controls [age: 64±9 (mean±SD) years] were asked to stand in front of a light and either turn to a specific light (predictable condition) or locate and turn to a random light (unpredictable condition) placed at 45°, 90° or 135° to the right or left when the light in front extinguished. There were five trials for each task and the tasks were randomized. The onset latency of the horizontal eye movement was measured by an eye camera (VNG Ulmer) and that of the horizontal head, shoulder, pelvis and feet movement were measured by CODA motion.
Results:
There was a top to bottom initiation of rotation of the segments when turning to unpredictable targets and a more simultaneous initiation of the segments when turning to predictable targets in both groups (interaction of segment
and predictability: F=27.004, p=0.001). However, this was not different between the stroke and control groups (Interaction of segment, predictability and group: F=2.887, p=0.082). In the unpredictable condition, there was more simultaneous onset of eye, head and shoulder movement when turning to 45 and 90 degrees as compared to more increasing latencies for the 135 degrees condition (interaction of segment, predictability and angle: F=19.443, p=0.001). There was no difference in the sequence of the segments when turning to both sides in the stroke participants (paretic/non‐paretic sides) and controls (right/left sides) (Interaction of segment, direction and group: F=0.300, p=0.876.
Conclusions:
Predictability of a target affects the sequence of rotation of segments during turning on the spot. The turn angle also affects the sequence when turning to unpredictable targets. The balance of an individual during a task is determined by the movement of the centre of mass within the base of support. This could be affected by the relative movement of the segments involved in the task. The clinical significance of the results of this study may be investigated by relating the sequence of the movement of the body segments to stability during turning. The similarity in the sequence between the groups may be due to motor and sensory deteriorations in the elderly."
Purpose
Objective measurement of mechanical properties of skeletal muscles in a clinical setti... more Purpose
Objective measurement of mechanical properties of skeletal muscles in a clinical setting is difficult. The present study examined inter-rater reliability of a new portable device for objective testing. Relevance Clinical measures of mechanical properties, such as muscle tone, are subjective. An objective tool would enable accurate assessment and monitoring of treatment efficacy.
Participants
Twenty one healthy men aged 20-35 years (mean 25.9, SD 4.4) with body mass index of 23.9 kg/m2 (SD 2.5) were studied.
Methods
Mechanical properties of rectus femoris (RF) and biceps brachii (BB) muscles on the dominant side were tested with the participant in relaxed supine lying. The MyotonPRO device was placed on the relevant muscle belly and applied mechanical taps which induced muscle oscillations, from which frequency (tone; Hz),decrement (elasticity; log), and stiffness (N/m) were measured. Two sets of 10 taps were applied to each muscle (mean of the two used for analysis) by two novice raters.
Analysis
Data were analysed using SPSS 18. Intraclass correlation coefficients (ICC) were used to assess intrarater within session reliability (ICC3,2) and between rater reliability (ICC3,1).
Results
Test-retest reliability for each rater in both muscles was excellent (ICC3,2 0.94-0.99). Inter-rater reliability was excellent for all RF parameters (ICC3,1 decrement 0.95; frequency 0.93; stiffness 0.92) and good to excellent for BB parameters (ICC3,1 decrement 0.78; frequency 0.84; stiffness 0.94).
Conclusions
The MyotonPRO device demonstrated excellent within-session intra-rater reliability and good to excellent inter-rater reliability for RF and BB in asymptomatic young males. Reliability needs to be established between days and for other muscles in healthy and clinical populations. Implications These findings demonstrate that different raters can obtain similar measurements for BB and RF muscles using the MyotonPRO in healthy young males. The device is therefore a potentially valuable tool for objective assessment of muscle in clinical and research settings.
Abstracts for the 8th World Congress on Aging and Physical Activity: A Celebration of Diversity and Inclusion in Active Ageing, 2012
Introduction: Myotonometry offers an objective, portable, non-invasive way of testing viscoelasti... more Introduction: Myotonometry offers an objective, portable, non-invasive way of testing viscoelastic properties (VP), such as tone and stiffness, of skeletal muscles. The present
study examined the differences between VP of healthy young and older males.
Methods: Forty-two healthy men were studied; 21 young and 21 older, mean and standard deviation (SD) for age and body mass index were 25.9 (4.4) years, 23.9 (2.5) kg/m2 and 72.1 (4.9) years, 25.2 (3.4) kg/m2 respectively. Participants were tested in supine lying with the leg extended and the muscle in a relaxed state. Viscoelastic properties of rectus femoris (RF)including decrement (elasticity), frequency (tone) and stiffness were measured using the MyotonPro (Muometria AS, Estonia). Damped oscillations of the muscle were recorded in response to a brief (15 milliseconds) mechanical tap applied by the probe with the device held perpendicular to the muscle surface. Two sets of 10 taps were taken and mean of the two used for analysis (t-tests).
Results: The means and standard deviations for young and older males were: decrement 1.4 (0.2) and 1.8 (0.3), frequency 16.1(1.1) and 16.3 (1.7) Hz, stiffness 288 (22.5) and 322.2 (27.9) N/m respectively. Differences for decrement and stiffness between the groups were statistically significant (p < 0.001) for both.
Conclusions: The MyotonPro enables rapid, objective assessment of viscoelastic properties, suitable for clinical/community settings. Age-related differences between the groups were greater decrement (lower elasticity) and stiffness of RF with ageing. The quadriceps muscles are important for mobility and the MyotonPro is potentially useful as a simple non-invasive device to detect decline in muscle characteristics with ageing and monitor effects of exercise interventions. Further studies of healthy females, other age ranges, and people with different levels of habitual activity are needed to provide reference data for assessing patients.
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Papers by Dinesh Samuel
"Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh. Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and these were compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5 mm to 2.9 mm (95% confidence intervals -0.6-8.3 mm), which were not statistically different (p > 0.05) and were highly correlated (ICCs 3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r = 0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle."
Purpose: To examine interrater and within-session reliability of using the MyotonPRO device for measuring non-neural tone
and mechanical properties of the rectus femoris and biceps brachii muscles in healthy young and older adults.
Methods: Forty-two healthy males were studied: n=21 aged 25.9 (SD 4.4) years and n=21 aged 72.1 (SD 4.9) years. The
MyotonPRO device applied brief, low force mechanical impulses to the muscle belly to produce damped oscillations of the
muscle at rest. Computing of the parameters was made automatically from the oscillation curve of non-neural mechanical
tone (state of intrinsic tension) measured as frequency [Hz], dynamic stiffness [N/m] and elasticity (logarithmic decrement).
Analysis: The means and standard deviations of all three parameters for each rater were calculated. Reliability was assessed
using intra-class correlation coefficients (ICCs) and Bland and Altman analysis.
Results: Excellent within-session intra-rater reliability was demonstrated by raters for both participant groups (intraclass
correlation coefficients, ICC 3,2 = 0.94-0.99). Interrater reliability was excellent for all rectus femoris parameters in the young
(ICC 3,1= 0.92-0.95) and older group (0.86-0.94). In biceps brachii, reliability was excellent in the young group (0.78-0.94) and
for elasticity in the older group (0.89) but was only classed as good for tone (0.67) and stiffness (0.68).
Conclusions: Different raters obtained acceptably similar results for all three parameters of rectus femoris in both age groups
and for biceps brachii in the young group, and for elasticity only in the older group. The findings indicate that the MyotonPRO
has potential use for objective assessment of mechanical muscle properties in clinical and research settings and that the
protocol for locating the site for testing biceps brachii in older participants could be modified to improve reliability.
Implications: The MyotonPRO device can be used reliably by different users to assess muscle parameters in healthy people
of different ages. Further studies are needed to add to the existing literature to establish Myoton technology as a valid and
reliable clinical and research tool for examining the effects of injury, disease and interventions in various muscles in clinical
conditions."
Background: Clinical assessments of muscle tone are subjective, often using the non-affected side for comparison. The MyotonPRO offers portable, non-invasive, objective measurement of mechanical properties of muscles.
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied. Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels
"
Method: Thirty one active female recreational golfers, aged 65-77 years, carried out three movement control tests included in the screening tool. Performance was video-recorded to enable repeated ratings. Each test was evaluated by criteria which were rated as pass or fail and ratings were carried out three weeks apart to examine intra-rater reliability. Reliability was assessed using percentage agreement and Cohen’s Kappa.
Results: Percentage agreement for each test ranged from 93.0-97.3%, with an overall mean agreement of 95.5%. Kappa values for test scores ranged from 0.35-0.90. Percentage agreement for individual criteria ranged from 83.0-100.0%, with kappa values ranging from 0.00-1.00.
Discussion: Acceptable intra-rater reliability was established for overall tests scores of the screening tool but certain criteria were identified as being less reliable than others. Recommendations are made for refinement of some criteria to improve reliability of the screening tool.
Aims: To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods: Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results: Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and nondominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions: High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.""
strength of the tester. The present study assessed the agreement between an adapted HHD and Biodex dynamometry while measuring knee extensor strength in young adults.
Method: Thirty participants aged 22–35 years (mean age 24.4 years; SD ± 2.5) were studied. Peak isometric knee extensor strength of the dominant leg was measured using the Biodex dynamometer and adapted HHD. The agreement between the maximum voluntary contractions (MVC) was analysed using Pearson’s Correlation Coefficient, intraclass correlation (ICC) and Bland–Altman analysis.
Results: The mean peak knee extensor MVC was 191.7 Nm (± 53.6) for the Biodex dynamometer and 167.5 Nm (± 55) for the adapted HHD. The mean difference in peak knee extensor strength measured using the adapted HHD was 24.1 Nm (± 30.3) lower when compared to the Biodex. However, there was good correlation between the two measures (r=0.796, ICC (3, 1): peak torque=0.796; average of three trials=0.808) and Bland–Altman plots confirmed good agreement.
Conclusions: The knee strength measurements were not influenced by examiner strength and results obtained using the adapted HDD were comparable to that using the Biodex; however, the absolute knee extensor strength obtained using the adapted HHD was generally lower.
Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
Objective
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh.Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and correlation using intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5mm to 2.9mm (95% confidence intervals -0.6 to 8.3mm), which were not statistically different (p>0.05) and were highly correlated (ICCs3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r=0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle.
Methods: Eighty-four healthy adults aged 60-88 years were tested. A torque dynamometer was utilised to measure muscle moments at the knee and hip joints. Functional assessment involved 3-D biomechanical analysis of gait, chair rise and sit-down, stair ascent and descent using an 8-camera VICON® system with Kistler force plates. HRQoL was assessed using the Short Form- 36 (SF-36) questionnaire.
Results: Spearman’s correlation coefficient showed significant correlation (p<0.001) between isometric strength and functional moments (r=0.24 to 0.67). Muscle strength was significantly correlated with SF-36 scores, including physical functioning, bodily pain, vitality, social functioning and role emotional scores. Knee flexion moment was correlated with role physical, vitality, social functioning, role emotional, mental health and mental component scores (r=0.24 to 0.40).
Conclusion: Loss of muscle strength is associated with poorer functional ability and both are associated with reduced HRQoL. The reduction of HRQoL is considerable in the physical functioning domain. Cause and effect was not established but studies need to be undertaken to evaluate the benefits of strength training, functional activity training or increased participation in life.
"
Methods: thirty-eight healthy volunteers aged 20–82 years performed maximal voluntary contractions (MVC) of quadriceps and handgrip using a custom-built transducer and a Jamar dynamometer respectively.
Results: the grip-quadriceps ratios for young adults was similar in males and females (0.75); indicating knee extensor force exceeded grip force by approximately 25%. Ratios were increased in older adults (p=0.05), and strength of the two muscle groups was approximately equal (1.1). Pearson’s correlation coefficients for grip against quadriceps strength were r=0.63 (young males), r=0.83 (young females), r=0.35 (older males) and r=0.05 (older females).
Conclusions: the ratio used demonstrated clear differences between the age groups. The reduced muscle strength with increasing age was expected but the higher grip/quadriceps strength ratios quantify a greater loss of quadriceps than grip strength with aging. It remains to be investigated whether the relatively greater rate of decline in quadriceps strength seen in healthy older people is more exaggerated in those who are frail, which would have implications for using grip strength as a physical marker of lower limb strength and function in those at risk of immobility and falls.
""
Turning around is a common activity of daily living. The location of a target may be known or unknown while angle and direction may vary prior to turning. A stroke can compromise coordination of body movement during turning.
Objectives
To investigate the effect of target predictability, turn angle and turn direction on the kinematic sequence of rotation of body segments in people with stroke and healthy controls when turning on-the-spot.
Methods
Ten people with stroke (age: 66 ± 10 years; 8 males) and 10 age-matched controls (age: 65 ± 8 years; 6 males) were asked to either turn to a specific light (predictable condition) or locate and turn to a random light (unpredictable condition) placed at 45°, 90° or 135° to the right or left when a light in front extinguished.
Results
People with stroke initiated movement of the segments significantly later than the controls (p = 0.014). The sequence of onset of rotation of the segments was not different between both groups. Target predictability affected the sequence of the segments; the eyes, head and shoulder started moving simultaneously when turning to unpredictable targets while the head and shoulder started moving before the eyes when turning to predictable targets. The sequence was also different across the three turn angles for each predictability condition. However, the sequence remained the same when turning to both sides in each group.
Conclusion
Similarities between the groups may be because the time since the stroke was long and therefore some recovery of function may have occurred. Slowness of movement in people with stroke may predispose them to falls.
The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mechanical properties (e.g. tone) and its reliability has yet to be established. Little is known about between-limb symmetry of mechanical properties in healthy older people, despite symmetry often being used as a measure of unilateral abnormalities in clinical assessment. Since quadriceps is important for mobility, it was selected for the present study.
Aims
To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods
Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results
Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and non-dominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions
High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.
Methods: Twenty one self-reported healthy adults, aged 65-84 years (Mean 73.5; SD 6.4 years). Participants were tested in a sitting position on two occasions, one week apart. The best of three attempts for PIF measured through the mouth, and five for each nostril for SNIP were recorded. Reliability was tested using intra-class correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC) and Bland and Altman analysis. Feedback on the measures in relation to ease of completion and preference was obtained using a semi-structured interview.
Results: Between-day reliability of SNIP and PIF were ICC3,1 0.76 (95% CI 0.49-0.9) and 0.92 (0.81-0.97) respectively. Standard error of measurement for SNIP (11.94 cmH2O) and MDC (33.10 cmH2O) were at the least 61% higher than for PIF. The participants reported difficulties in performing SNIP, rating it as being less easy and uncomfortable to perform than PIF, with a higher rate of missing data for SNIP due to participants’ dislike of test.
Conclusions: The wide range of SNIP readings, lower ICC value and negative user feedback is suggestive of a less robust and unacceptable clinical measure. PIF showed excellent reliability and acceptability and is therefore recommended for assessing inspiratory muscle strength in older people without known obstructive lung disease.
"
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied.
Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels.
"
"Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh. Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and these were compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5 mm to 2.9 mm (95% confidence intervals -0.6-8.3 mm), which were not statistically different (p > 0.05) and were highly correlated (ICCs 3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r = 0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle."
Purpose: To examine interrater and within-session reliability of using the MyotonPRO device for measuring non-neural tone
and mechanical properties of the rectus femoris and biceps brachii muscles in healthy young and older adults.
Methods: Forty-two healthy males were studied: n=21 aged 25.9 (SD 4.4) years and n=21 aged 72.1 (SD 4.9) years. The
MyotonPRO device applied brief, low force mechanical impulses to the muscle belly to produce damped oscillations of the
muscle at rest. Computing of the parameters was made automatically from the oscillation curve of non-neural mechanical
tone (state of intrinsic tension) measured as frequency [Hz], dynamic stiffness [N/m] and elasticity (logarithmic decrement).
Analysis: The means and standard deviations of all three parameters for each rater were calculated. Reliability was assessed
using intra-class correlation coefficients (ICCs) and Bland and Altman analysis.
Results: Excellent within-session intra-rater reliability was demonstrated by raters for both participant groups (intraclass
correlation coefficients, ICC 3,2 = 0.94-0.99). Interrater reliability was excellent for all rectus femoris parameters in the young
(ICC 3,1= 0.92-0.95) and older group (0.86-0.94). In biceps brachii, reliability was excellent in the young group (0.78-0.94) and
for elasticity in the older group (0.89) but was only classed as good for tone (0.67) and stiffness (0.68).
Conclusions: Different raters obtained acceptably similar results for all three parameters of rectus femoris in both age groups
and for biceps brachii in the young group, and for elasticity only in the older group. The findings indicate that the MyotonPRO
has potential use for objective assessment of mechanical muscle properties in clinical and research settings and that the
protocol for locating the site for testing biceps brachii in older participants could be modified to improve reliability.
Implications: The MyotonPRO device can be used reliably by different users to assess muscle parameters in healthy people
of different ages. Further studies are needed to add to the existing literature to establish Myoton technology as a valid and
reliable clinical and research tool for examining the effects of injury, disease and interventions in various muscles in clinical
conditions."
Background: Clinical assessments of muscle tone are subjective, often using the non-affected side for comparison. The MyotonPRO offers portable, non-invasive, objective measurement of mechanical properties of muscles.
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied. Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels
"
Method: Thirty one active female recreational golfers, aged 65-77 years, carried out three movement control tests included in the screening tool. Performance was video-recorded to enable repeated ratings. Each test was evaluated by criteria which were rated as pass or fail and ratings were carried out three weeks apart to examine intra-rater reliability. Reliability was assessed using percentage agreement and Cohen’s Kappa.
Results: Percentage agreement for each test ranged from 93.0-97.3%, with an overall mean agreement of 95.5%. Kappa values for test scores ranged from 0.35-0.90. Percentage agreement for individual criteria ranged from 83.0-100.0%, with kappa values ranging from 0.00-1.00.
Discussion: Acceptable intra-rater reliability was established for overall tests scores of the screening tool but certain criteria were identified as being less reliable than others. Recommendations are made for refinement of some criteria to improve reliability of the screening tool.
Aims: To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods: Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results: Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and nondominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions: High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.""
strength of the tester. The present study assessed the agreement between an adapted HHD and Biodex dynamometry while measuring knee extensor strength in young adults.
Method: Thirty participants aged 22–35 years (mean age 24.4 years; SD ± 2.5) were studied. Peak isometric knee extensor strength of the dominant leg was measured using the Biodex dynamometer and adapted HHD. The agreement between the maximum voluntary contractions (MVC) was analysed using Pearson’s Correlation Coefficient, intraclass correlation (ICC) and Bland–Altman analysis.
Results: The mean peak knee extensor MVC was 191.7 Nm (± 53.6) for the Biodex dynamometer and 167.5 Nm (± 55) for the adapted HHD. The mean difference in peak knee extensor strength measured using the adapted HHD was 24.1 Nm (± 30.3) lower when compared to the Biodex. However, there was good correlation between the two measures (r=0.796, ICC (3, 1): peak torque=0.796; average of three trials=0.808) and Bland–Altman plots confirmed good agreement.
Conclusions: The knee strength measurements were not influenced by examiner strength and results obtained using the adapted HDD were comparable to that using the Biodex; however, the absolute knee extensor strength obtained using the adapted HHD was generally lower.
Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI.
Objective
This study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh.Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and correlation using intra-class correlation coefficients (ICC 3,1). Mean differences between the linear measures taken from the MRI and RUSI were -0.5mm to 2.9mm (95% confidence intervals -0.6 to 8.3mm), which were not statistically different (p>0.05) and were highly correlated (ICCs3,1 0.84-0.94). Correlations between the three linear measurements and muscle CSA ranged from r=0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness. Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle.
Methods: Eighty-four healthy adults aged 60-88 years were tested. A torque dynamometer was utilised to measure muscle moments at the knee and hip joints. Functional assessment involved 3-D biomechanical analysis of gait, chair rise and sit-down, stair ascent and descent using an 8-camera VICON® system with Kistler force plates. HRQoL was assessed using the Short Form- 36 (SF-36) questionnaire.
Results: Spearman’s correlation coefficient showed significant correlation (p<0.001) between isometric strength and functional moments (r=0.24 to 0.67). Muscle strength was significantly correlated with SF-36 scores, including physical functioning, bodily pain, vitality, social functioning and role emotional scores. Knee flexion moment was correlated with role physical, vitality, social functioning, role emotional, mental health and mental component scores (r=0.24 to 0.40).
Conclusion: Loss of muscle strength is associated with poorer functional ability and both are associated with reduced HRQoL. The reduction of HRQoL is considerable in the physical functioning domain. Cause and effect was not established but studies need to be undertaken to evaluate the benefits of strength training, functional activity training or increased participation in life.
"
Methods: thirty-eight healthy volunteers aged 20–82 years performed maximal voluntary contractions (MVC) of quadriceps and handgrip using a custom-built transducer and a Jamar dynamometer respectively.
Results: the grip-quadriceps ratios for young adults was similar in males and females (0.75); indicating knee extensor force exceeded grip force by approximately 25%. Ratios were increased in older adults (p=0.05), and strength of the two muscle groups was approximately equal (1.1). Pearson’s correlation coefficients for grip against quadriceps strength were r=0.63 (young males), r=0.83 (young females), r=0.35 (older males) and r=0.05 (older females).
Conclusions: the ratio used demonstrated clear differences between the age groups. The reduced muscle strength with increasing age was expected but the higher grip/quadriceps strength ratios quantify a greater loss of quadriceps than grip strength with aging. It remains to be investigated whether the relatively greater rate of decline in quadriceps strength seen in healthy older people is more exaggerated in those who are frail, which would have implications for using grip strength as a physical marker of lower limb strength and function in those at risk of immobility and falls.
""
Turning around is a common activity of daily living. The location of a target may be known or unknown while angle and direction may vary prior to turning. A stroke can compromise coordination of body movement during turning.
Objectives
To investigate the effect of target predictability, turn angle and turn direction on the kinematic sequence of rotation of body segments in people with stroke and healthy controls when turning on-the-spot.
Methods
Ten people with stroke (age: 66 ± 10 years; 8 males) and 10 age-matched controls (age: 65 ± 8 years; 6 males) were asked to either turn to a specific light (predictable condition) or locate and turn to a random light (unpredictable condition) placed at 45°, 90° or 135° to the right or left when a light in front extinguished.
Results
People with stroke initiated movement of the segments significantly later than the controls (p = 0.014). The sequence of onset of rotation of the segments was not different between both groups. Target predictability affected the sequence of the segments; the eyes, head and shoulder started moving simultaneously when turning to unpredictable targets while the head and shoulder started moving before the eyes when turning to predictable targets. The sequence was also different across the three turn angles for each predictability condition. However, the sequence remained the same when turning to both sides in each group.
Conclusion
Similarities between the groups may be because the time since the stroke was long and therefore some recovery of function may have occurred. Slowness of movement in people with stroke may predispose them to falls.
The MyotonPRO (Myoton Ltd; London) is a new portable device for measuring muscle mechanical properties (e.g. tone) and its reliability has yet to be established. Little is known about between-limb symmetry of mechanical properties in healthy older people, despite symmetry often being used as a measure of unilateral abnormalities in clinical assessment. Since quadriceps is important for mobility, it was selected for the present study.
Aims
To investigate: (i) between-day intra-rater reliability of a novice user of MyotonPRO; (ii) between-side symmetry of mechanical properties of quadriceps in older males.
Methods
Twenty healthy, community dwelling, right-lower-limb-dominant males (mean age 71.7, range 65–82 years) were studied. With the participant in relaxed supine lying, the MyotonPRO applied two consecutive sets of 10 taps to induce muscle oscillations of rectus femoris, from which measurements of decrement (elasticity), frequency (tone), and stiffness were obtained. Tests were performed on two occasions at the same time and day of the week, one week apart.
Results
Repeated measurements had very high within-day (intraclass correlation coefficient, ICC 3,1 > 0.90) and high between-day (ICC 3,2 > 0.70; mean of two measurement sets) reliability. There was no statistically significant difference between muscle mechanical properties of the dominant and non-dominant muscles (<2.5% difference; p > 0.05), thereby indicating symmetry.
Conclusions
High intra-rater reliability was established for MyotonPRO measurements of quadriceps in healthy older males, which were symmetrical between sides. These findings indicate that larger studies are warranted to establish normal reference ranges of data with which to compare patients with muscle abnormalities.
Methods: Twenty one self-reported healthy adults, aged 65-84 years (Mean 73.5; SD 6.4 years). Participants were tested in a sitting position on two occasions, one week apart. The best of three attempts for PIF measured through the mouth, and five for each nostril for SNIP were recorded. Reliability was tested using intra-class correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC) and Bland and Altman analysis. Feedback on the measures in relation to ease of completion and preference was obtained using a semi-structured interview.
Results: Between-day reliability of SNIP and PIF were ICC3,1 0.76 (95% CI 0.49-0.9) and 0.92 (0.81-0.97) respectively. Standard error of measurement for SNIP (11.94 cmH2O) and MDC (33.10 cmH2O) were at the least 61% higher than for PIF. The participants reported difficulties in performing SNIP, rating it as being less easy and uncomfortable to perform than PIF, with a higher rate of missing data for SNIP due to participants’ dislike of test.
Conclusions: The wide range of SNIP readings, lower ICC value and negative user feedback is suggestive of a less robust and unacceptable clinical measure. PIF showed excellent reliability and acceptability and is therefore recommended for assessing inspiratory muscle strength in older people without known obstructive lung disease.
"
Objective: This study aimed to investigate between-limb symmetry for mechanical properties of biceps brachii (BB) in older males and within-session intra-rater reliability of a novice user of the MyotonPRO device.
Methods: Twenty community-dwelling, right-handed males aged 65-85 years (mean 71.7; SD ± 4.9) were studied.
Exclusion criteria: history of neurological and musculoskeletal conditions, medications affecting muscle tone, and body mass index >30 kg/m2. The device applied 10 mechanical impulses at one second intervals, producing damped oscillations, from which frequency (non-neural tone), stiffness and logarithmic decrement (elasticity) were measured. With the participant resting supine, two consecutive sets of 10 recordings were taken bilaterally from BB.
Results: Percentage mean differences between-sides for larger and smaller values were 12% (tone), 14% (stiffness) and 27% (elasticity), which were statistically significant (p<0.001). Within-session reliability was excellent for all three parameters (ICC 3,2: all 0.99). Bland and Altman plots confirmed good agreement, without bias.
Conclusion: Symmetry of BB mechanical properties in a group of older males was less than 15% for tone and stiffness but not elasticity. Within-session intra-rater reliability of a novice user was excellent for all three parameters. Reliability over different days needs to be investigated. These findings indicate potential clinical application of the MyotonPRO for assessing abnormalities of muscle parameters in patients with neurological or musculoskeletal conditions, using comparison with the contralateral side (absolute difference), as well as databases of normative reference values from healthy control groups of different ages, gender and activity levels.
"
""
Turning around to interact with the environment is a common activity of daily living. The location of a target for interaction may be known or unknown prior to turning and the angle of a turn may vary depending on the task to be carried out. A stroke can compromise coordination of body movement during turning] which may pose a risk for instability and subsequent falls. The aim of this study was to investigate the kinematic sequence of rotation of body segments in people with stroke and healthy controls when turning on the spot to predictable and unpredictable targets placed at three different angles (45°, 90° and 135°).
Methods:
Nine people with stroke [age: 64±9 (mean±SD) years] and nine healthy controls [age: 64±9 (mean±SD) years] were asked to stand in front of a light and either turn to a specific light (predictable condition) or locate and turn to a random light (unpredictable condition) placed at 45°, 90° or 135° to the right or left when the light in front extinguished. There were five trials for each task and the tasks were randomized. The onset latency of the horizontal eye movement was measured by an eye camera (VNG Ulmer) and that of the horizontal head, shoulder, pelvis and feet movement were measured by CODA motion.
Results:
There was a top to bottom initiation of rotation of the segments when turning to unpredictable targets and a more simultaneous initiation of the segments when turning to predictable targets in both groups (interaction of segment
and predictability: F=27.004, p=0.001). However, this was not different between the stroke and control groups (Interaction of segment, predictability and group: F=2.887, p=0.082). In the unpredictable condition, there was more simultaneous onset of eye, head and shoulder movement when turning to 45 and 90 degrees as compared to more increasing latencies for the 135 degrees condition (interaction of segment, predictability and angle: F=19.443, p=0.001). There was no difference in the sequence of the segments when turning to both sides in the stroke participants (paretic/non‐paretic sides) and controls (right/left sides) (Interaction of segment, direction and group: F=0.300, p=0.876.
Conclusions:
Predictability of a target affects the sequence of rotation of segments during turning on the spot. The turn angle also affects the sequence when turning to unpredictable targets. The balance of an individual during a task is determined by the movement of the centre of mass within the base of support. This could be affected by the relative movement of the segments involved in the task. The clinical significance of the results of this study may be investigated by relating the sequence of the movement of the body segments to stability during turning. The similarity in the sequence between the groups may be due to motor and sensory deteriorations in the elderly."
Objective measurement of mechanical properties of skeletal muscles in a clinical setting is difficult. The present study examined inter-rater reliability of a new portable device for objective testing. Relevance Clinical measures of mechanical properties, such as muscle tone, are subjective. An objective tool would enable accurate assessment and monitoring of treatment efficacy.
Participants
Twenty one healthy men aged 20-35 years (mean 25.9, SD 4.4) with body mass index of 23.9 kg/m2 (SD 2.5) were studied.
Methods
Mechanical properties of rectus femoris (RF) and biceps brachii (BB) muscles on the dominant side were tested with the participant in relaxed supine lying. The MyotonPRO device was placed on the relevant muscle belly and applied mechanical taps which induced muscle oscillations, from which frequency (tone; Hz),decrement (elasticity; log), and stiffness (N/m) were measured. Two sets of 10 taps were applied to each muscle (mean of the two used for analysis) by two novice raters.
Analysis
Data were analysed using SPSS 18. Intraclass correlation coefficients (ICC) were used to assess intrarater within session reliability (ICC3,2) and between rater reliability (ICC3,1).
Results
Test-retest reliability for each rater in both muscles was excellent (ICC3,2 0.94-0.99). Inter-rater reliability was excellent for all RF parameters (ICC3,1 decrement 0.95; frequency 0.93; stiffness 0.92) and good to excellent for BB parameters (ICC3,1 decrement 0.78; frequency 0.84; stiffness 0.94).
Conclusions
The MyotonPRO device demonstrated excellent within-session intra-rater reliability and good to excellent inter-rater reliability for RF and BB in asymptomatic young males. Reliability needs to be established between days and for other muscles in healthy and clinical populations. Implications These findings demonstrate that different raters can obtain similar measurements for BB and RF muscles using the MyotonPRO in healthy young males. The device is therefore a potentially valuable tool for objective assessment of muscle in clinical and research settings.
study examined the differences between VP of healthy young and older males.
Methods: Forty-two healthy men were studied; 21 young and 21 older, mean and standard deviation (SD) for age and body mass index were 25.9 (4.4) years, 23.9 (2.5) kg/m2 and 72.1 (4.9) years, 25.2 (3.4) kg/m2 respectively. Participants were tested in supine lying with the leg extended and the muscle in a relaxed state. Viscoelastic properties of rectus femoris (RF)including decrement (elasticity), frequency (tone) and stiffness were measured using the MyotonPro (Muometria AS, Estonia). Damped oscillations of the muscle were recorded in response to a brief (15 milliseconds) mechanical tap applied by the probe with the device held perpendicular to the muscle surface. Two sets of 10 taps were taken and mean of the two used for analysis (t-tests).
Results: The means and standard deviations for young and older males were: decrement 1.4 (0.2) and 1.8 (0.3), frequency 16.1(1.1) and 16.3 (1.7) Hz, stiffness 288 (22.5) and 322.2 (27.9) N/m respectively. Differences for decrement and stiffness between the groups were statistically significant (p < 0.001) for both.
Conclusions: The MyotonPro enables rapid, objective assessment of viscoelastic properties, suitable for clinical/community settings. Age-related differences between the groups were greater decrement (lower elasticity) and stiffness of RF with ageing. The quadriceps muscles are important for mobility and the MyotonPro is potentially useful as a simple non-invasive device to detect decline in muscle characteristics with ageing and monitor effects of exercise interventions. Further studies of healthy females, other age ranges, and people with different levels of habitual activity are needed to provide reference data for assessing patients.