|Title:||An electromyographic study of normal shoulder muscle activation patterns during abduction and adduction|
|Authors:||Reed, Darren Scott|
|Publisher:||University of Sydney.|
School of Medical Sciences.
|Abstract:||Background: Abduction and adduction are common movements of the shoulder used in everyday functional activities, clinical assessment of the shoulder and rehabilitation/ exercise programs to improve the function at the shoulder. However, the normal recruitment patterns of the shoulder muscles during these movements are not fully understood. Aim: To establish a normative data base of muscle activation patterns and levels during adduction and abduction and to determine whether load and plane of movement affect these parameters. Methods: Eleven shoulder muscles were investigated using a combination of intramuscular and surface electrodes during adduction and abduction in five experiments involving cohorts of 15 asymptomatic subjects. Exercises were performed at low, medium and high loads. Abduction was also performed in three different planes and as a shoulder press exercise. Results: Normative data bases of shoulder muscle activation patterns and levels were established for adduction, abduction and the shoulder press. Load did not change the activation pattern in any exercise and plane of movement had no effect on activation parameters in the majority of muscles tested during abduction. No single muscle was shown to initiate abduction. Activation patterns during abduction and the shoulder press were very different. Conclusions: Adduction and abduction are complex exercises that require coordinated muscle activity of axio/scapulo-humeral (latissimus dorsi, pectoralis major, middle deltoid, teres major), rotator cuff (subscapularis, infraspinatus and supraspinatus) and axio-scapular muscles (upper trapezius, lower trapezius, serratus anterior and rhomboid major). These results may be useful in planning effective rehabilitation and exercise programs.|
|Access Level:||Access is restricted to staff and students of the University of Sydney . UniKey credentials are required. Non university access may be obtained by visiting the University of Sydney Library.|
|Rights and Permissions:||The author retains copyright of this thesis. It may only be used for the purposes of research and study. It must not be used for any other purposes and may not be transmitted or shared with others without prior permission.|
|Type of Work:||PhD Doctorate|
|Type of Publication:||Doctor of Philosophy Ph.D.|
|Appears in Collections:||Sydney Digital Theses (University of Sydney Access only)|
|REED Darren Scott - Final Thesis.pdf||PhD Thesis||5.55 MB||Adobe PDF|
Items in Sydney eScholarship Repository are protected by copyright, with all rights reserved, unless otherwise indicated.