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Trunk and shoulder kinematic and kinetic and electromyographic adaptations to slope increase during motorized treadmill propulsion among manual wheelchair users with a spinal cord injury.

Gagnon D, Babineau AC, Champagne A, Desroches G, Aissaoui R - Biomed Res Int (2015)

Bottom Line: To quantify muscular demand, the electromyographic activity (EMG) of the pectoralis major (clavicular and sternal portions) and deltoid (anterior and posterior fibers) was recorded during the experimental tasks and normalized against maximum EMG values obtained during static contractions.Overall, forward trunk flexion and shoulder flexion increased as the slope became steeper, whereas shoulder flexion, adduction, and internal rotation moments along with the muscular demand also increased as the slope became steeper.The results confirm that forward trunk flexion and shoulder flexion movement amplitudes, along with shoulder mechanical and muscular demands, generally increase when the slope of the treadmill increases despite some similarities between the 2.7° to 3.6° and 3.6° to 4.8° slope increments.

View Article: PubMed Central - PubMed

Affiliation: School of Rehabilitation, Université de Montréal, Montreal, QC, Canada H3C 3J7 ; Pathokinesiology Laboratory, Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal, Institut de Réadaptation Gingras-Lindsay-de-Montréal, 6300 Darlington, Montreal, QC, Canada H3S 2J4.

ABSTRACT
The main objective was to quantify the effects of five different slopes on trunk and shoulder kinematics as well as shoulder kinetic and muscular demands during manual wheelchair (MWC) propulsion on a motorized treadmill. Eighteen participants with spinal cord injury propelled their MWC at a self-selected constant speed on a motorized treadmill set at different slopes (0°, 2.7°, 3.6°, 4.8°, and 7.1°). Trunk and upper limb movements were recorded with a motion analysis system. Net shoulder joint moments were computed with the forces applied to the handrims measured with an instrumented wheel. To quantify muscular demand, the electromyographic activity (EMG) of the pectoralis major (clavicular and sternal portions) and deltoid (anterior and posterior fibers) was recorded during the experimental tasks and normalized against maximum EMG values obtained during static contractions. Overall, forward trunk flexion and shoulder flexion increased as the slope became steeper, whereas shoulder flexion, adduction, and internal rotation moments along with the muscular demand also increased as the slope became steeper. The results confirm that forward trunk flexion and shoulder flexion movement amplitudes, along with shoulder mechanical and muscular demands, generally increase when the slope of the treadmill increases despite some similarities between the 2.7° to 3.6° and 3.6° to 4.8° slope increments.

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Related in: MedlinePlus

Group averaged time-normalized profile (solid line) and standard deviation (dotted line) of the shoulder and trunk kinematics (a, b, c, and d) and weight-normalised shoulder moments (e, f, and g) during the push phase for the five slopes tested at self-selected natural speed.
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fig2: Group averaged time-normalized profile (solid line) and standard deviation (dotted line) of the shoulder and trunk kinematics (a, b, c, and d) and weight-normalised shoulder moments (e, f, and g) during the push phase for the five slopes tested at self-selected natural speed.

Mentions: The trunk and shoulder movement patterns are illustrated in Figures 2(a), 2(b), 2(c), and 2(d), whereas the minimum, maximum, and excursion of the trunk and shoulder movement amplitudes are summarized in Table 4. The slopes of the treadmill significantly influenced most minimum, maximum, and excursion trunk and shoulder movement amplitudes. At the trunk, all minimum, maximum, and excursion movement amplitudes significantly increased as the slope became steeper, except for minimum and maximum values during the 2.7° to 3.6° slope increment that remained similar. The greatest maximum forward trunk flexion (60.9°), which was accompanied by the greatest forward trunk excursion (22.4°), was reached during the 7.1° slope. At the shoulder, the maximum shoulder flexion movement amplitude significantly increased as the slope became steeper, except for the 3.6° to 4.8° slope increment that remained similar, whereas the minimum shoulder flexion movement amplitude (i.e., shoulder extension) significantly decreased during that same period. As a result, the shoulder flexion excursion remained comparable despite slope increments. The minimum, maximum, and excursion shoulder abduction movement amplitudes remained comparable as the slope became steeper. The minimum, maximum and excursion shoulder internal rotation movement amplitudes also remained comparable as the slope became steeper, with the exception of the minimum and excursion values, which significantly increased during the 0° to 2.7° slope increment.


Trunk and shoulder kinematic and kinetic and electromyographic adaptations to slope increase during motorized treadmill propulsion among manual wheelchair users with a spinal cord injury.

Gagnon D, Babineau AC, Champagne A, Desroches G, Aissaoui R - Biomed Res Int (2015)

Group averaged time-normalized profile (solid line) and standard deviation (dotted line) of the shoulder and trunk kinematics (a, b, c, and d) and weight-normalised shoulder moments (e, f, and g) during the push phase for the five slopes tested at self-selected natural speed.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4352451&req=5

fig2: Group averaged time-normalized profile (solid line) and standard deviation (dotted line) of the shoulder and trunk kinematics (a, b, c, and d) and weight-normalised shoulder moments (e, f, and g) during the push phase for the five slopes tested at self-selected natural speed.
Mentions: The trunk and shoulder movement patterns are illustrated in Figures 2(a), 2(b), 2(c), and 2(d), whereas the minimum, maximum, and excursion of the trunk and shoulder movement amplitudes are summarized in Table 4. The slopes of the treadmill significantly influenced most minimum, maximum, and excursion trunk and shoulder movement amplitudes. At the trunk, all minimum, maximum, and excursion movement amplitudes significantly increased as the slope became steeper, except for minimum and maximum values during the 2.7° to 3.6° slope increment that remained similar. The greatest maximum forward trunk flexion (60.9°), which was accompanied by the greatest forward trunk excursion (22.4°), was reached during the 7.1° slope. At the shoulder, the maximum shoulder flexion movement amplitude significantly increased as the slope became steeper, except for the 3.6° to 4.8° slope increment that remained similar, whereas the minimum shoulder flexion movement amplitude (i.e., shoulder extension) significantly decreased during that same period. As a result, the shoulder flexion excursion remained comparable despite slope increments. The minimum, maximum, and excursion shoulder abduction movement amplitudes remained comparable as the slope became steeper. The minimum, maximum and excursion shoulder internal rotation movement amplitudes also remained comparable as the slope became steeper, with the exception of the minimum and excursion values, which significantly increased during the 0° to 2.7° slope increment.

Bottom Line: To quantify muscular demand, the electromyographic activity (EMG) of the pectoralis major (clavicular and sternal portions) and deltoid (anterior and posterior fibers) was recorded during the experimental tasks and normalized against maximum EMG values obtained during static contractions.Overall, forward trunk flexion and shoulder flexion increased as the slope became steeper, whereas shoulder flexion, adduction, and internal rotation moments along with the muscular demand also increased as the slope became steeper.The results confirm that forward trunk flexion and shoulder flexion movement amplitudes, along with shoulder mechanical and muscular demands, generally increase when the slope of the treadmill increases despite some similarities between the 2.7° to 3.6° and 3.6° to 4.8° slope increments.

View Article: PubMed Central - PubMed

Affiliation: School of Rehabilitation, Université de Montréal, Montreal, QC, Canada H3C 3J7 ; Pathokinesiology Laboratory, Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal, Institut de Réadaptation Gingras-Lindsay-de-Montréal, 6300 Darlington, Montreal, QC, Canada H3S 2J4.

ABSTRACT
The main objective was to quantify the effects of five different slopes on trunk and shoulder kinematics as well as shoulder kinetic and muscular demands during manual wheelchair (MWC) propulsion on a motorized treadmill. Eighteen participants with spinal cord injury propelled their MWC at a self-selected constant speed on a motorized treadmill set at different slopes (0°, 2.7°, 3.6°, 4.8°, and 7.1°). Trunk and upper limb movements were recorded with a motion analysis system. Net shoulder joint moments were computed with the forces applied to the handrims measured with an instrumented wheel. To quantify muscular demand, the electromyographic activity (EMG) of the pectoralis major (clavicular and sternal portions) and deltoid (anterior and posterior fibers) was recorded during the experimental tasks and normalized against maximum EMG values obtained during static contractions. Overall, forward trunk flexion and shoulder flexion increased as the slope became steeper, whereas shoulder flexion, adduction, and internal rotation moments along with the muscular demand also increased as the slope became steeper. The results confirm that forward trunk flexion and shoulder flexion movement amplitudes, along with shoulder mechanical and muscular demands, generally increase when the slope of the treadmill increases despite some similarities between the 2.7° to 3.6° and 3.6° to 4.8° slope increments.

Show MeSH
Related in: MedlinePlus