Pectoral and Axillary Regions Flashcards
What four bony parts makes up the pectoral region?
Clavicles
Sternum (manubrium, body, xiphoid)
Ribs
Scapula
Which region are ribs found in? What do they articulate with?
Found in thoracic region
Articulate with vertebra posteriorly and sternum anteriorly
Which are the atypical ribs?
Which ones are true ribs? What makes them true?
Which ones are false ribs? What makes them false?
Which ones are floating ribs?
Atypical=1, 2, 11 & 12
True= 1-7 (vertebrocostal: each rib has its own cartilagenous attachment to sternum–no sharing cartilage bw ribs)
False=8-10 (vertebrochondral: coverges with rib 7 and doesn’t directly attach to sternum like the true ribs)
Floating= Dont attach to sternum, only attach to vertebra posteriorly
Which rib attaches to xiphosternal joint?
7th rib
Which part of vertebra attaches to head of rib? Which part attaches to tubercle of rib?
Demifacet attaches to head, transverse facet on transverse process attaches to tubercle of rib
What attaches at the angle of the rib?
intrinsic back musles
Mammary glands are _____
modified sweat glands
Retromammary space is potential space between ____ and ____
breast and pectoral fascia
The breast is what kind of structure? What is the breast innervated by?
Cutaneous structure, modified sweat gland that rests on pectoral fascia (above pec major)
innervated by intercostal nerves
What ligament attaches the breast to the dermis of overlying skin?
Suspensory ligament (Cooper’s ligament)
What converges on the nipple? What opens at the nipple?
Mammary gland lobules converge on nipple
15-20 lactiferous ducts open at nipple which is surrounded by pigmented areola
Arterial supply of breast tissue?
mammary branches from anterior intercostal, lateral thoracic and internal thoracic arteries
venous drainage of breast tissue?
mainly to axillary vein via lateral thoracic veins and medial mamary veins
some drainage to internal thoracic vein via anterior intercostal veins
Why is lymphatic drainage to breast tissue important? where is most of the lymph from breast tissue drained into? What are the other 2 routes it can drain lymph?
Bc of its role in metastasis of cancer cells
>75% of lymph from breast drains into axillary lymph nodes (pectoral, central, apical)
remaining drains into parasternal and abdominal lymph nodes
The nipple, areola and lactiferous lobules drain into subareolar lymph nodes
Innervation of breast tissue
mainly from anterior and lateral branches of 4th-6th intercostal nerves
some innervation from supraclavicular nerve branches and other intercostal nerves
Polymastia & polythelia
Supernumerary breasts or nipples
What muscles lie within the clavipectoral fascia?
Pec MINOR and subclavius
What muscles make up the delto/clavipectoral triangle? what major structure lies in this triangle?
Deltoid, pec MAJOR and clavicle
the confluence of axillary vein and subclavian vein becoming cephalic vein?? (check answer)
What structures lie within the superficial fascia of pectoral region?
Platysma
supraclavicular nerves
anterior and lateral branches of intercostal nerves
Borders and structures of deltopectoral triangle
Borders: deltoid, pec major and middle 3rd of clavicle
Structures: cephalic vein, deltopectoral lymph nodes, deltoid branch of thoracoacromial a (from axillary a)
Clavipectoral fascia invests what muscles? Where does the fascia attach? What neurovascular strucures are there/peirce it? What does it become?
Invests subclavius and pec minor
attaches to clavicle and anterior thoracic wall
cephalic vein, thoracolumbar a and lateral pectoral nerves pierce it
becomes suspensory ligament of axilla
What four muscles are found in the pectoral region? What (generally speaking) innervates them?
Pec major, pec minor, subclavius, serratus anterior
Innervated by ventral rami of spinal nerves via branches of brachial plexus
