2.2.5. Anterior Shoulder Flashcards Preview

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Flashcards in 2.2.5. Anterior Shoulder Deck (22)

What are four functions of the thoracic wall(cage)

Protect vital organs Resist negative internal pressure generated by elastic recoil of the lungs Provide attachment for upper limbs Provide anchoring attachment of many muscles that move and maintain limbs


What are the landmarks of the sternum

Jugular notch

Angle of Louis(aka sternal angle



xiphoid process


What anatomical levels does the sternal angle mark?

The second pair of coastal cartilages.


What is the infrasternal angle?

The angle formed by the cartilage of the false ribs and the inferior angle of the xiphoid process


What is the difference between the true and false ribs


What ribs have a coastal groove? What is the function of the coastal groove?


Which rib has the scalene turbucle?

Rib 1.  The scalene turbucle is the attachment point for the anterior scaleneus muscule.  





What is poland syndrome

Unilateral absence of both pectorali muscles, often associated with other ipsilateral limb deformities.



What is pectus excavatum

condition of a caved in chest due to rib overgrowth.  contrast with pectus carinatum undergrowth of the ribs causing the chest to bow outward.


Pec major Origin, Insertion, Innervation, Blood supply, Main action (OIIBM)

Origin: Sternal half of clavicle, sternum to 7th rib, aponeurosis of EO

Insertion: lateral lip of intertubercular sulcus of humerus

Innervation: Medial and lateral pectoral nerves

Blood supply: pectoral branche of thoraco-acromial artery

Main action: flexes and adducts arm, rotates medially


Pec Minor O.I.I.B.M.

Origin: Upper margin of rib 3-5

Insertion: coracoid process of scapula

Innervation: Medial pectoral nerves 

Blood supply: pectoral branche of thoraco-acromial artery

Main action: lowers the lateral angle of scapula, protracts scapula


Serratus A.  OIIBM

Origin: lateral surface of 8-9 ribs

Insertion: coastal surface, medial border of scapula

Innervation: Long thoracic

Blood supply: Lateral thoracic a.

Main action: protracts scapula/holds it against thoracic wall



1. Medial pectoral nerve***

2. Lateral pectoral nerve

3. Pec. minor

** Medial pectoral nerve is LATERAL to the lateral pectoral nerve.  easy to distinguish because the medial nerve goes through pec minor and also innervates pec major, where the lateral pec nerve BYPASSES mec pinor.


What is winged scapula?  Which NERVE injury causes this problem and what disability does the patient have? Why is the long thoracic nerve exceptional?

 - Paralysis of Serratus anterior by injuring the long thoracic nerve is one cause of a winged scapula.  

-The upper limb may not be able to be abducted above horizontal position because the serratus anterior is unable to rotate the glenoid cavity superiorly to allow complete ABduction of the limb.  

-long thoracic nerve is exceptional in that it is superficial to the serratus anterior


What is important about cephalic vein

It is an important landmark since it is supercifical in the delto-pectoral groove and provide DIRECT intravenous access to the superior vena cava.  


Why is the tail of spence important?

Can be confused with a lump or enlarged lymph nodes when enlarged during menstrual cycle. 

On occasion, fibrous tissue that is palpa


Intercostobrachial nerves?

Innervates the medial skin of the upper arm as well as the lateral, upper thorax and axilla.  IT can be injured during breast surgery


What are the quadrants of the breast?

Think clock face.

superomedial 0-3

inferomedial 3-6

inferolateral 6-9

superolateral 9-12 






What is gynomastia?

slight enlargement of the breast (hypertrophy) due to imbalance between estrogenic and androgenic hormones.  Associated with Klinefelter syndrome (40%)


What is polythelia?

accessory nipples.


How does lymph flow out of the breast?

generally flows toward the nipple then lateral side of breast flows to ipsilateral pectoral nodes and into axial.  medial side of breast parasternal nodes and to contralateral breast