Anat Cell Biol.  2020 Dec;53(4):505-508. 10.5115/acb.20.058.

An unusual finding of the pectoralis major muscle: decussation of sternal fibers across the midline

• Burley H
• Georgiev GP
• Iwanaga J
• Dumont AS
• Tubbs RS

• KMID: 2509697
• DOI: http://doi.org/10.5115/acb.20.058

Abstract

Variations of the pectoralis major muscle are commonly seen. However, during the routine dissection of an adult male cadaver, an apparently uncommon muscular variant was identified. In this cadaver, the sternal heads of the left and right pectoralis muscles crossed the midline and interdigitated with one another. In addition, the clavicular heads of both pectoralis major muscles were separated from the remaining parts of the muscles. Such anatomical variants such be kept in mind by clinicians and surgeons during patient evaluation and treatment.

Keyword

Pectorais muscles; Anatomic variation; Anatomy; Cadaver

Figure

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  Fig. 1 Anterior view of the specimen described in the present report. Note the bilaterally separated clavicular heads of the pectoralis major muscle. Also, the sternocostl fibers are seen decussating across the midline over the sternum.

Reference

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