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A newly reported muscle: an accessory infraspinatus or a deep layer of the latissimus dorsi?
Krzysztof Koptas1, Nicol Zielinska1, R Shane Tubbs2,3,4,5,6,7
1Department of Anatomical Dissection and Donation, Medical University of Lodz, Lodz, Poland.
Abstract:
The infraspinatus muscle is a component of the rotator cuff; the latissimus dorsi muscle is the largest muscle of the back. These muscles are not considered very morphologically variable. However, the latissimus dorsi has more frequent variations than the infraspinatus. During anatomical dissection, an additional muscle structure was found. It originated on the medial border of the scapula, ran under the scapular spine, and ended on the greater tubercle next to the infraspinatus attachment. We will discuss the anatomical and physiological relationships of this muscle. We believe that our finding underlines the importance of different muscle variants in the rotator cuff region. Level of evidence: II basic science research.
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