Anterior and posterior musculotendinous anatomy of the supraspinatus
The objective of this study was to quantitatively describe the supraspinatus musculotendinous architecture. After supraspinatus muscles were harvested from 25 embalmed shoulders, each muscle was divided into an anterior and posterior muscle belly on the basis of muscle fiber insertion. Pennation ang...
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Published in | Journal of shoulder and elbow surgery Vol. 9; no. 5; pp. 436 - 440 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
Mosby, Inc
01.09.2000
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Subjects | |
Online Access | Get full text |
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Summary: | The objective of this study was to quantitatively describe the supraspinatus musculotendinous architecture. After supraspinatus muscles were harvested from 25 embalmed shoulders, each muscle was divided into an anterior and posterior muscle belly on the basis of muscle fiber insertion. Pennation angles and musculotendinous dimensions were measured, and the physiologic cross-sectional area was calculated for each muscle belly. The physiologic cross-sectional areas of the anterior and posterior bellies were calculated to be 140 ± 43 mm 2 and 62 ± 25 mm2, respectively, whereas, their tendon cross-sectional areas were 26.4 ± 11.3 mm2 and 31.2 ± 10.1 mm2, respectively. The average anterior-to-posterior ratios for the muscle physiologic cross-sectional area and the tendon cross-sectional area were 2.45 ± 0.82 and 0.87 ± 0.30, respectively. Thus, a larger anterior muscle pulls through a smaller tendon area. These data suggest that physiologically, anterior tendon stress is significantly greater than posterior tendon stress and that rotator cuff tendon repairs should incorporate the anterior tendon whenever possible, inasmuch as it functions as the primary contractile unit. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1058-2746 1532-6500 |
DOI: | 10.1067/mse.2000.108387 |