breast and pectoral region

  1. Acomioclavicular joint functionsImage Upload 1
    Plane type synovial joint

    Connects clavicle and scapula
  2. Image Upload 2Sternoclavicular joint functions
    Saddle type joint and connects the scapula to the thorax via clavicle

    Functions as ball and socket to accommodate movements of the scapula
  3. Faciae of pectoral region 4 and location
    Deltoid fascia – descends from clavicle, acromion, and scapular spine, continuous with the pectoral fascia anteriorly infraspinous fascia posteriorly

    Pectoral fascia – descends from clavicle and sternum, inveting pectoralis major, become the axillary fascia laterally

    Axillary fascia – continuation of pectoral fascia, forms the flood of the axilla

    Clavipectoral fascia – descends from clavicle, encloses the subclavius and pectoralis minor, continuous with axillary fascia
  4. Image Upload 3Pectoralis major actions, innervation, insertion, origin
    A: both heads adduct and medially rotate humerus, clavicular head flexes humerus, sternocostal head extends humerus from flexed position

    IV: lateral pectoral nerve and medial pectoral nerve

    IN: lateral lip of intertubercular sulcus

    O: clavicular head: anterior surface of medial clavicle

    Sternocostal head: anterior surface of sternum and superior 6 costal cartilages
  5. Image Upload 4Pectoralis minor actions, innervation, insertion, origin
    A: stabilizes scapula by drawing it inferiorly and anteriorly against the thoracic wall

    IV: medial petoral nerve

    IN: coracoid process

    Origin: ribs 3-5 near their costal cartilages
  6. Image Upload 5Subclavius actions, innervation, insertion, origin
    A: anchor and depresses clavicle

    IV: nerve to subclavius

    IN: inferior middle clavicle

    O: junction of the 1st rib and costal cartilage
  7. Serratus anterior actions, innervation, insertion, origin
    A: protects scapula, holds scapula against the thoracic wall, superior rotation of the scapula

    IV: long thoracic nerve

    IN: anterior surface of medial border of scapula

    O: lateral parts of ribs 1-8
  8. Fracture of clavicle cause and symptoms
    C; direct fall onto shoulder, indirect due to transmission of force from arm and forearm to shoulder during fall

    S: medial fragment is elevated due to sternomastoid, lateral fragment is depressed due to weight of the arm

    *injured subclavian vein causing internal bleeding
  9. Axillary sheath defineImage Upload 6
    • Sleeve like extension of the cervical fascia
    • (fascia - a band or sheath of connective tissue investing, supporting, or binding together internal organs or parts of the body)
  10. 3 contents within axillary sheath

    2 contents outside of axillary sheath
    W: axillary artery and branches, axillary vein and tributaries, brachial plexus (cords and branches)

    O: axillary lymph nodes and lymphatic vessels, axillary fat
  11. Image Upload 7Subclavian artery characteristics 2
    Arises from the brachiocephalic trunk (which arises from the aorta) on the RIGHT side, &

    directly from the arch of the aorta on the LEFT

    Becomes the axillary artery at the lateral border of the 1st rib
  12. Axillary artery break down
    Subclavian artery becomes acillary artery at lateral border of 1st rib, the axillary artery can be divided into 3 parts, axillary artery becomes the brachial artery at the inferior border of teres major
  13. 1st part of axillary artery locationImage Upload 8

    Located between the 1st rib & the medial border of pectoralis minor

    Enclosed within the axillary sheath

    1st section has 1 branch
  14. Image Upload 92 Nd part of axillary artery location
    • Lies posterior to pectoralix minor
    • 2nd section as 2 branches:
  15. Thoracoacromial artery divides into 4 branches:




    Lateral thoracic artery
  16. 3rd part of axillary artery location and branchesImage Upload 10
    Rom lateral border of pectoralis minor to inferior border of teres major

    3 branches are: posterior circumflex humeral artery, anterior circumflex humeral artery, subscapular artery which divides into 2 branches (circumflex (bend around something else) scapular artery, thoracodorsal artery)
  17. AXILLARY VEIN locationImage Upload 11
    union of the brachial vein & basilic vein

    changes the name at the lateral border of the 1st rib to subclavian vein (same as subclavian & axillary artery)

    **union of the brachial veins & basilic Vein contains 3 parts (corresponds to 3 parts of axillary artery) becomes subclavian vein at the lateral border of the 1st rib (same as subclavian & axillary artery)
  18. CEPHALIC VEIN location
    a superficial, subcutaneous vein of the lateral aspect of the upper limb

    travels through the deltopectoral groove & pierces the clavipectoral fascia at the deltopectoral triangle draining into the axillary vein

    **cephalic vein drains into axillary vein, brachial veins accompanying the brachial artery
  19. Common variants in breasts
    Polymastia: accessory breast

    Polythelia: accessory nipples

    Amastia: no breast development

    Gynecomastia: breast hypertrophy in males

    breast tissue typically extends transversely from the lateral border of the sternum to the midaxillary line & vertically from the 2nd to 6th rib
  20. **at puberty, the lactiferous ducts give rise to 15-20 lobules of the mammary gland which constitute the parenchyma (functional part of the breast tissue) each gland is drained by a lactiferous duct, which dilates into a sinus (lactiferous sinus), & narrows again into a duct (lactiferous duct)
  21. Lateral thoracic artery location and function
    Branch of axillary artery

    Gives lateral mammary branches
  22. Internal thoracic artery location and function
    Branch of subclavian atery

    Gives medial mammary branches from anterior intercostal arteries
  23. Posterior intercostal arteries location and function
    Generally branches from thoracic aorta

    Gives lateral mammary branches from lateral cutaneous branches
  24. Nerves of breast characteristics 4
    Transmitted from the anterior & lateral cutaneous branches of the 4th-6th intercostal nerves

    They pierce the pectoral fascia to reach subcutaneous tissue & skin

    Somatic sensory fibers to skin, sympathetic to blood vessels & smooth muscles of skin & nipples

    Nipple sits at T4 dermatome (see Brachial Plexus lecture for more on dermatomes
  25. Lymph drainage of breast explained
    Lymph passes from nipple, areola, & lobules to the Subareolar lymphatic plexus. Axillary lymph nodes receive >75% of lymph from the breast, largely from the lateral quadrants (superior lateral & inferior lateral) most common sites for mestasis from breast cancer From the medial quadrants, lymph passes mostly to the parasternal lymph nodes; lymph can travel via the parasternal lymph nodes to

    the contralateral breast. Subdiaphgragmatic lymph nodes receives lymph typically from the inferior quadrant.3 sets of lymph nodes form the base (humeral, subscapular, & pectoral) which drain into central lymph nodes, draining into apical lymph nodes of the lymph traveling to the axillary lymph nodes from the breast, most travels FIRST to the pectoral lymph nodes
  26. **carcinomas of the breast are malignant tumors usually adenocarcinoma arising from the epithelial cell of the lactiferous ducts in the mammry gland lobules**
  27. Cancer interference with lymphatic drainage symptoms and Lymphedema define
    Excess fluid in subcutaneous tissue, deviation of nipple leather like appearance of skin, orange peel look to skin, puffy prominent skin between dimples (dimple due to shortening of suspensory ligaments
  28. Cancer invading glandular tissue symptoms
    Large dimple

    Dimples caused by shortening or traction placed on suspensory ligaments
  29. Cancer invade retromammary space, pectoral fascia, or interpectoral lymph nodes symptoms
    Breasts elevates when muscle contract (places hand on hips)

    Sign of advanced breast cancer

    Invasion of pectoral fascia characteristic of rock hard fixed nodule
  30. Subareolar breast cancer symptom
    Retraction and deviation of nipple caused by shortening of lactiferous ducts
  31. 2 types of breast surgery
    Lumpectomy (radiation therapy)

    Mastectomy (remove breast, simple, modified radical)
  32. Breast density of post-menopausal women, pregnant women, obese
  33. Less dense, increased breast density, decreased density
  34. **breast density on mammogram cannot be predicted by palpitation and age cannot be predictor of breast density
Card Set
breast and pectoral region
RUSM breast and pectoral region WEEK 1 FUNDAMENTALS 1