Upper limb Pectoral region Dr Amal Albtoosh Pectoral

Upper limb Pectoral region Dr Amal Albtoosh

Pectoral muscles 2

The Pectoral Region v. The pectoral region is located on the anterior chest wall. v It contains I. Four muscles that exert a force on the upper limb: 1. Subclavian. 2. The Pectoralis major 3. Pectoralis minor 4. Serratus anterior II. Breast 3

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The Pectoral Region The Breasts • The breasts, although strictly speaking, are not anatomically part of the upper limb; they are situated in the pectoral region (anterior chest wall). • They are present in both sexes. • they are similar in structure in males and immature females, • An adult female the breast has the The subcutaneous tissue that supports the mammary glands and the mammary glands determines the size of a subcutaneous tissue. breast. 5

The Pectoral Region Location and Description • The breasts are specialized accessory glands of the skin that secrete milk. • The level of the breast is Rib 2–Rib 6 , and the level of the nipple, located at the centre of the breast, is Rib 4. 6

The Pectoral Region In each breast: Ø less than 20 mammary glands produce milk Ø Milk flows through the corresponding lactiferous ducts. Ø The milk is stored in lactiferous sinuses. Ø In the subcutaneous tissue, there are suspensory ligaments of breast to maintain the shape of the breast. Ø The areola, coloured area, which surrounds the nipple, secretes oil to help during lactation 7

The Pectoral Region Blood Supply Arteries: The branches to the breasts include the: ü perforating branches of the internal thoracic artery and ü the intercostal arteries. ü The axillary artery also supplies the gland via its lateral thoracic and thoracoacromial branches. Veins The veins correspond to the arteries. 8

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The pectoral region Lymph Drainage of breast v The lateral quadrants of the breast drain into: the anterior axillary or pectoral group of nodes (situated just posterior to the lower border of the pectoralis major muscle). v The medial quadrants drain by means of vessels that pierce the intercostal spaces and enter the internal thoracic group of nodes (situated within the thoracic cavity along the course of the internal thoracic artery). 10

The Pectoral Region v. A few lymph vessels follow the posterior intercostal arteries and drain posteriorly into the posterior intercostal nodes (situated along the course of the posterior intercostal arteries); vsome vessels communicate with the lymph vessels of the opposite breast and with those of the anterior abdominal wall. 11