Background: Shoulder external rotation at abduction (ER) is a notable motion in overhead sports because it could cause strong stress to the elbow and shoulder joint. However, no study has comprehensively investigated the effect of different trunk postures during ER. This study aimed to investigate the effect of different trunk postures on scapular kinematics and muscle activities during ER.
Methods: Fourteen healthy men performed active shoulder external rotation at 90° of abduction with the dominant arm in 15 trunk postures. At maximum shoulder external rotation in 15 trunk postures, including 4 flexion-extension, 6 trunk rotation, and 4 trunk side-bending postures, as well as upright posture as a control, scapular muscle activities and kinematics were recorded using surface electromyography and an electromagnetic tracking device, respectively. The data obtained in the flexion-extension, trunk rotation, and trunk side-bending postures were compared with those obtained in the upright posture.
Results: In the flexion-extension condition, scapular posterior tilt and external rotation significantly decreased, but the muscle activities of the lower trapezius and infraspinatus significantly increased in maximum trunk flexion. Moreover, scapular upward rotation and the activity of the serratus anterior significantly increased in maximum trunk extension. In the rotation condition, scapular posterior tilt and external rotation significantly decreased, but the activity of the serratus anterior significantly increased in the maximum contralateral trunk rotation posture. In the trunk side-bending condition, scapular posterior tilt and the external rotation angle significantly decreased.
Conclusion: Trunk postures affected scapular kinematics and muscle activities during ER. Our results suggest that different trunk postures activate the lower trapezius and serratus anterior, which induce scapular posterior tilt.
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http://dx.doi.org/10.1016/j.jse.2019.04.059 | DOI Listing |
eNeurologicalSci
March 2025
Department of Neurology, Nagoya City University Graduate School of Medical Sciences, Aichi, Japan.
L-type calcium channel antagonists are uncommon causes of myoclonus, and the underlying mechanism remains unclear. Here, we report a case of parkinsonian syndrome with deterioration of preexisting myoclonus after nifedipine use. A 96-year-old woman was administered a single dose of sustained-release nifedipine for chest pain.
View Article and Find Full Text PDFEur J Neurosci
January 2025
Human Performance Research Centre, University of Konstanz, Constance, Germany.
Lightly touching a solid object reduces postural sway. Here, we determine the effect of artificially modifying haptic feedback for balance. Participants stood with their eyes closed, lightly gripping a manipulandum that moved synchronously with body sway to systematically enhance or attenuate feedback gain between +2 and -2, corresponding to motion in the same or opposite direction to the body, respectively.
View Article and Find Full Text PDFPeerJ
January 2025
Department of Orthopedics, Xuanwu Hospital Capital Medical University, Beijing, China.
Background: Lifting is generally considered as a risk factor for low back pain. A thorough investigation of the muscle function during lifting is essential for a better assessment of the potential risk of muscle impairment and towards improvements in lifting strategy. We aimed to compare the activities of the trunk muscles between the stoop and the squat lifting tasks.
View Article and Find Full Text PDFJ Clin Med
December 2024
Pető András Faculty, Semmelweis University, 1125 Budapest, Hungary.
Cerebral palsy (CP) manifests with abnormal posture and impaired selective motor control, notably affecting trunk control and dynamic balance coordination, leading to inadequate postural control. Previous research has indicated the benefits of pulsed electromagnetic field (PEMF) therapy for various musculoskeletal and neurological conditions. Therefore, we conducted a randomized pilot study to assess the feasibility of our preliminary research design and examine the effect of the PEMF treatment among children with CP.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Unidad de Investigación en Fisioterapia, Spin off Centro Clínico OMT-E Fisioterapia SLP, Universidad de Zaragoza, Domingo Miral s/n, 50009 Zaragoza, Spain.
The anatomy of the pelvis may obscure differences in pelvic tilt, potentially underestimating its correlation with clinical measures. Measuring the total sagittal range of pelvic movement can serve as a reliable indicator of pelvic function. This study assessed the inter- and intra-examiner reliability of the Kinovea version 0.
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