Vol 65, No 1 (2006)
Case report
Published online: 2005-12-05
A case of an anomalous pectoralis major muscle
Folia Morphol 2006;65(1):100-103.
Abstract
We present a case of a right sided accessory head of the pectoralis major muscle
located inferior to its abdominal head. This variation was found during a routine
anatomy dissection at the American University of the Caribbean School of Medicine.
The muscle fibres of the accessory head of the pectoralis major muscle arose
from those of the serratus anterior muscle and travelled superolaterally towards
the axilla. The accessory muscle terminated by fusing with the tendinous fibres of
the pectoralis major muscle as they underwent their normal anatomical rotation
before insertion upon the lateral lip of the bicipital groove of the humerus.
Although variations in the pectoral muscles are not uncommon, this case appears
to be unique in the literature. The possible clinical implications are discussed.
Keywords: anomalous pectoralis major musclepectoralis minor muscleserratus anterior musclemedial pectoral nervelateral thoracic arteryaxillary arch