Return to search

Measuring humeral head translation after suprascapular nerve block

xiii, 79 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Subacromial impingement syndrome is the most common disorder of the shoulder. Abnormal superior translation of the humeral head is believed to be one of the major causes of this pathology. The overall purpose of this study was to better understand glenohumeral kinematics in normal healthy individuals using fluoroscopy to help comprehend the mechanism of shoulder impingement. This research was divided into three sections: a validation study to measure humeral head translation, a comparison between dynamic and static arm elevation and lastly, humeral head translation after a suprascapular nerve block.

In the first study, fluoroscopy was used to take images of human cadaver shoulders. Scapular orientation was manipulated in different positions while the humerus was at 90 degrees of elevation. Humeral head translation was measured using two methods and was compared to the known translation. Additionally, the accuracy of the contour registration method to measure 2-D scapular rotations was assessed.

For the second study, subjects elevated their dominant arm while fluoroscopic images were taken. An edge detection software was utilized to digitize points on both the humeral head and glenoid. Humeral head translation and scapular upward rotation were measured using a contour registration method with respect to the glenoid during arm elevation. Five different arm elevation angles were investigated to measure differences in humeral head translation between trials. There was no difference found between humeral head translation and scapular upward rotation between static and dynamic shoulder elevation.

For the third study, humeral head translation was measured before and after a suprascapular never block. The humeral head was superiorly located and the scapula was more upwardly rotated after the block. The differences were observed during mid range of motion. This result showed that there was a compensatory increase in both humeral head translation and scapular upward rotation due to the nerve block. These results suggest that increasing muscular strength and endurance of the supraspinatus and infraspinatus muscle could prevent any increased superior humeral head translation. This may be beneficial in preventing shoulder impingement or rotator cuff tear over time. This dissertation includes unpublished co-authored materials. / Committee in charge: Andrew Karduna, Chairperson, Human Physiology;
Li-Shan Chou, Member, Human Physiology;
Louis Osternig, Member, Human Physiology;
Stephen Frost, Outside Member, Anthropology

Identiferoai:union.ndltd.org:uoregon.edu/oai:scholarsbank.uoregon.edu:1794/10325
Date09 1900
CreatorsSan Juan, Bernardo G., 1977-
PublisherUniversity of Oregon
Source SetsUniversity of Oregon
Languageen_US
Detected LanguageEnglish
TypeThesis
RelationUniversity of Oregon theses, Dept. of Human Physiology, Ph. D., 2009;

Page generated in 0.0018 seconds