PRELIMS: THORAX - REGIONAL ANATOMY (PECTORAL REGION) Flashcards
The region external to the anterior thoracic wall and helps anchor the upper limb to the trunk.
PECTORAL REGION
What are the components of the pectoral region
~SUPERFICIAL COMPARTMENT
~DEEP COMPARTMENT
The compartment that consists of the skin, superficial fascia, and breasts
SUPERFICIAL FASCIA
The compartment that consists of the muscles and associated structures
DEEP FASCIA
Structures that emerge from the thoracic wall, axilla, and neck
~NERVES
~VESSELS
~LYMPHATICS
FROM THE SUPERFICIAL COMPARTMENTS
Components of breast
~MAMMARY GLANDS
~ASSOCIATED SKIN
~CONNECTIVE TISSUES
Modified sweat glands in the superficial fascia anterior to the pectoral muscle and anterior thoracic wall
Consist of a series of ducts and associated secretory lobules
MAMMARY GLANDS
Mammary glands converge to form this
It also open independently into the nipple
15 TO 20 LACTIFEROUS DUCTS
The nipple is surrounded by a circular pigmented area that is called what?
AREOLA
Well developed structure that surrounds the ducts and lobules of the mammary gland
CONNECTIVE TISSUE STROMA
A well defined ligament that is formed by condensed connective tissue stroma that is continuous with the dermis of the skin and supports the breast.
SUSPENSORY LIGAMENTS OF BREAST
Creates tension on ligaments that causes pitting of the skin
CARCINOMA OF THE BREAST
What is the predominant component of breast in nonlactating women
FAT
What is the predominant component of breast in lactating women
GLANDULAR TISSUE
Lies on the deep fascia related to the pectoralis major muscle and the other surrounding muscle
BREAST
A layer of loose connective tissue that separates the breast from the deep fascia and provides some degree of movement over underlying structures
RETROMAMMARY SPACE
How does the base, or the attached surface of each breast extends?
VERTICALLY= FROM RIBS 2 TO 6 TRANSVERSELY= FROM STERNUM TO MIDAXILLARY LINE
TRUE OR FALSE:
The breasts is related to the thoracic wall and to structures associated with the upper limb which means that vascular supply and drainage can occur by multiple routes
TRUE
The vascular supply and drainage that occurs laterally
VESSELS FROM THE AXILLARY ARTERY ~SUPERIOR THORACIC ~THORACO-ACROMIAL ~LATERAL THORACIC ~SUB-SCAPULAR ARTERIES
The vascular supply and drainage that occurs medially
BRANCHES FROM THE INTERNAL THORACIC ARTERY
Where does the vascular and drainage supply happen for the 2nd to 4th intercostal arteries?
BRANCHES THAT PERFORATES THE THORACIC WALL AND OVERLYING MUSCLE
The veins that drains the breast is parallel to the arteries and then drains into the axillary, internal thoracic, and intercostal veins
STATEMENT TO REMEMBER FOR THE VENOUS DRAINAGE OF THE PECTORAL REGION
Where is the breast innervated?
VIA ANTERIOR AND LATERAL CUTANEOUS BRANCHES OF THE 2ND TO 6TH INTERCOSTAL NERVES
What innervates the nipples
4TH INTERCOSTAL NERVES
75% of the Lymphatic drainage that drains laterally and superiorly into axillary nodes
LYMPHATIC VESSELS
TRUE OR FALSE
Most of the remaining drainage happens into the parasternal nodes deep to the anterior thoracic wall and associated with the internal thoracic artery
TRUE
TRUE OR FALSE
Some drainage may occur via lymphatic vessels that follow the lateral branches of posterior intercostal arteries and connect with intercostal nodes situated near the heads and necks of ribs
TRUE
Nodes that drain into the subclavian trunk.
AXILLARY NODES
Nodes that drain into the bronchomediastinal trunks
PARASTERNAL NODES
Nodes that drains into the thoracic duct or bronchomediastinal trunks
INTERCOSTAL NODES
Describe the breast in men
RUDIMENTARY AND CONSISTS ONLY OF SMALL DUCTS AND CORDSOF CELLS THAT DOES NOT NORMALLY EXTEND BEYOND THE AREOLA
YES OR NO:
Can breast cancer occur in men
YES
One of the most common malignancies in women that develops in the cell of acini, lactiferous ducts and lobules of the breast
BREAST CANCER
Depends on the exact cellular site of the origin of cancer
TUMOR GROWTH AND SPREAD
Factors that affects the response to surgery
~CHEMOTHERAPY
RADIOTHERAPY
Spreads via the lymphatics and veins or by direct invasion
BREAST TUMOR
How is the diagnosis of breast cancer confirmed
BIOPSY AND HISTOLOGICAL EVALUATION
Steps in staging the tumors
- size of primary tumor
- exact site of primary tumor
- number and sites of lymph node spread
- organs to which thetumor may have spread
A procedure that may be carried out to look for any spread to the lungs, liver, or bones
COMPUTED TOMOGRAPHY SCANNING OF THE BODY
Tumor spread to the lungs
PULMONARY METASTASES
Tumor spread in the liver
HEPATIC METASTASES
Tumor spread in the bone
BONY METASTASES
Further imaging that uses radioactive isotopes that is avidly taken up by tumor metastases in bone
BONE SCANNING
A procedure that can visualize active foci of the metastatic disease in the body
PET-CT
TRUE OR FALSE:
Lymph drainage of the breast is complex
TRUE
Where does lymph vessels pass through
IT PASSES THROUGHAXILLARY, SUPERCLAVICULAR, AND PARASTERNAL NODES AND MAY EVEN PASS TO ABDOMINAL LYMPHNODES, AS WELL AS TO THE OPPOSITE BREAST.
TRUE OR FALSE:
Containment of nodal metastatic breast cancer is potentially difficult because it can spread through many lymph node groups
TRUE
What does the subcutaneous lymphatic obstruction and growth pull on that results in peau d’orange on the surface of the breast
CONNECTIVE TISSUE LIGAMENTTS IN THE BREAST
Further subcutaneous spread of tumor can induce a rare manifestation of breast cancer that produces a hard, woody texture to the skin called what?
CANCER EN CUIRASSE
a surgical procedure that involves the excision of breast tissue
MASTECTOMY
Damage to this nerve can result in paralysis of the serratus anterior muscle, producing a “winged” scapula
THORACIC NERVE
What are the 3 muscles of the pectoral region
~PECTORALIS MAJOR
~PECTORALIS MINOR
~SUBCLAVIUS
Where does the muscles of the pectoral region originate from?
FROM THE ANTERIOR THORACIC WALL AND INSERT INTO BONES OF THE UPPER LIMB
What is the largest and most superficial muscle of the pectoral region muscles?
It also has a broad origin that includes the anterior surfaces of the medial half of the clavicle, sternum, and related costal cartilages.
PECTORALIS MAJOR
The pectoralis major directly underlies this structure which is separated by the deep fascia and the loose connective tissue of the retromammary space
BREAST
What are the origin of the pectoralis major?
~MEDIAL HALF OF THE CLAVICLE AND ANTERIORSURFACE OF THE STERNUM
~FIRST SEVEN COSTAL CARTILAGES
~APONEUROSIS OF EXTERNAL OBLIQUE
What are the insertion of the Pectoralis major
~LATERAL LIP OF INTERTUBERCULAR SULCUS OF HUMERUS
What are the innervations of the Pectoralis major
~MEDIAL PECTORAL NERVES
~LATERAL PECTORAL NERVES
What are the functions of the Pectoralis major?
~ADDUCTION
~MEDIAL ROTATION
~FLEXION OF THE HUMERUS AT THE SHOULDER JOINT
IT ALSO ADDUCTS, FLEXES, AND MEDIALLY ROTATES THE ARM
What are the origin of the subclavius?
RIB 1 AT THE JUNCTION BETWEEN RIB AND COSTAL CARTILAGE
What are the insertion of the subclavius?
GROOVE ON THE INFERIOR SURFACE OF MIDDLE THIRD OF CLAVICLE
What are the innervations of the subclavius?
NERVE TO SUBCLAVIUS
What are the functions of the subclavius?
~PULLS THE CLAVICLE MEDIALLY TO STABILIZE STERNOCLAVIVULAR JOINT
~DEPRESSES TIP OF SHOULDER
What are the origin of the pectoralis minor?
~ANTERIORSURFACE OF THE 3RD, 4TH, AND 5TH RIBS
~DEEP FASCIA OVERLYING THE RELATED INTERCOSTAL SPACES
What are the insertion of the pectoralis minor?
CORACOID PROCESS OF THE SCAPULA
What are the innervations of pectoralis minor?
MEDIAL PECTORAL NERVES
What are the functions of the pectoralis minor?
~DEPRESSES THE TIP OF THE SHOULDER
~PROTRACTS THE SCAPULA
Muscle fibers converge to form what structures that inserts into the lateral lip of the intertubercular sulcus of the humerus?
FLAT TENDON
What are the Muscles of the pectoral region that lies under the pectoralis major that pulls the tip of the shoulder inferiorly?
~SUBCLAVIUS
~PECTORALIS MINOR
A small muscle that passes laterally from the anterior and medial part of rib 1 to the inferior surface of the clavicle
SUBCLAVIUS
A muscle that passes from the anterior surfaces of rib 3 to 5 to the coracoid process of the scapula
PECTORALIS MINOR
A continuous layer of deep fascia that encloses the subclavius and the pectoralis minor and attaches to the clavicle above and to the floor of the axilla below
CLAVIPECTORAL FASCIA
What forms the anterior wall of the axilla?
MUSCLES OF PECTORAL REGION
A region between the upper limb and the neck through which all major structures pass
ANTERIOR WALL OF AXILLA