Vol. 9 No. 1 (2006)
Case Report

Unilateral Four-Headed Pectoralis Muscle Major

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  • Rasheed Bani Hammad,
  • Adel Mohamed
DOI: https://doi.org/10.26443/mjm.v9i1.500

Published 2020-12-01

Keywords

  • accessory tendon,
  • biceps brachii,
  • pectoralis muscle,
  • Poland syndrome

How to Cite

1.
Hammad RB, Mohamed A. Unilateral Four-Headed Pectoralis Muscle Major. McGill J Med [Internet]. 2020 Dec. 1 [cited 2025 Oct. 6];9(1). Available from: https://mjm.mcgill.ca/article/view/500
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Abstract

A unilateral four-headed pectoralis major muscle was observed on the left side of an 83 year-old Caucasian male cadaver. The accessory tendon arises from the lateral aspect of the pectoralis major muscle, travels along with the tendon of the long head of the biceps brachii and blends into the capsule of the shoulder joint. This anomaly is rare. A complete or partial absence of pectoralis major muscle is normally reported. Additionally, supernumerary heads of muscles other than pectoralis major have been documented. However, the existence of an accessory tendon to the pectoralis major muscle is unique. The implications of such a finding are discussed.

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References

  1. Gray H. In: Gray's Anatomy. New York Williams-Warwick- Dyson-Bannister, 1989.
  2. Swieter, M.G. and Carmichael. Bilateral three-headed biceps brachii muscles. Anatomischer Anzeiger. 148:346-349; 1980.
  3. Beals RK and Crawford S. Congenital absence of the pectoral muscle. Clinical orthopaedics. 1976; 119:166.
  4. Snell RS. In: Clinical Anatomy for Medical Students. Baltimore, MD. Boston Little, Brown and Company, 1995.
  5. Pierach CA. [Missing major pectoral muscle] (German). Fortschritte auf dem Gebiete der Rontgenstrahlen und derNuklearmedizin. 1973; 118(2): 225-6.
  6. Samilson R L. Congenital and developmental anomalies of the shoulder girdle. Orthopedic Clinics of North America. 1980; 11(2): 219-231.
  7. Segall HD. Congenital absence of the pectoralis major muscle. Medical Radiography and Photography. 1972; 48(1): 23.
  8. Almstead, S. Congenital defects of the pectoral muscles. Lancet. 1933; 1:1179.
  9. Christopher, F. Congenital absence of the pectoral muscles. The Journal of Bone and Joint Surgery. 1928; 10:350-351.
  10. Samuel. E. Congenital absence of the pectoralis major. British Journal of Radiology. 1945; 18:20-21.
  11. Armendares S. Letter: Absence of pectoralis major muscle in two sisters associated with leukemia in one of them. The Journal of Pediatrics. 1974; 85(3): 436-7.
  12. Frias JL, Felman AH. Absence of the pectoralis major, with ipsilateral aplasia of the radius, thumb, hemidiaphragm and lung: an extreme expression of poland anomaly? Birth Defects Original Article Series. 1974; 10(5): 55-9.
  13. Urschel HC Jr. Polands syndrome. Chest Surgery Clinics of North America. 2000; 10(2): 393-403.
  14. Mosconi T, Kamath S. Bilateral asymmetric deficiency of the pectoralis major muscle. Clinical Anatomy. 2003; 16(4):346-9.
  15. Debeer P, Brys P, De Smet L, Fryns JP. Unilateral absence of the trapezius and pectoralis major muscle: a variant of Poland syndrome. Genetic Counseling. 2002; 13(4):449-53.
  16. Yazar F, Kirici Y, Ozan H. Accessory insertions of pectoralis major muscle to the brachial fascia: a case report. Kaibogaku Zasshi Journal of Anatomy. 1998; 73(6): 637-9.