Upper Extremity Flashcards
What does the scapular spine divide?
Divides dorsal surface intro supraspinous and infraspinous fossae
What is the acromial angle?
Where spine bends at spinoglenoid notch
Lateral border of scapula
- From inferior angle to glenoid cavity
- widens superiorly as infraglenoid tubercle
Medial border of scapula
From inferior angle to superior angle
Superior border of the scapula
Superior angle to suprascapular notch
Inferior angle of scapula
Overlies 7th intercostal space (rib)
Superior angle of scapula
Medial to superior border
Lateral angle of scapula contains what?
- glenoid cavity
- glenohumeral joint
- supra- and infraglenoid tubercles
- an anatomical neck
- surgical neck
Coracoid process
- From top of head of scapula
- points laterally and anteriorly
Clavicle articulates with?
Manubrium of the sternum and acromion of scapula
Acromial end of clavicle
Flattened for articulation with acromion
Sternal end of clavicle
Enlarged for articulation with the manubrium of sternum and 1st costal cartilage
Shaft of cartilage
- Medial 2/3 convex anteriorly
- lateral 1/3 concave anteriorly
Humerus
The arm or brachial extends from shoulder to elbow
Head of humerus articulates with?
Glenoid cavity– glenohumeral joint
What are the greater and lesser tubercles of the humerus separated by?
Intertubercular groove/sulcus (aka bicipital groove)
Where is the anatomical neck?
Lies between the head and tubercles
Surgical neck of humerus
Lies at the beginning of the body or shaft, distal to the tubercles
-more likely region of breakage
Deltoid tuberosity
- anterolateral “bump”
- insertion of deltoid muscle
Radial groove
- aka spiral groove
- posterior aspect
- position of radial nerve
Trochlea of humerus articulates with?
Ulna
Where is the sulcus for ulnar nerve?
Lateral to trochlea in the deep groove
What does the capitulum articulate with?
Radius
What are the 2 parts of the coracoclavicular ligament?
- conoid (more medial)
- trapezoid ligaments
What muscles make up the rotator cuff?
-supraspinatus
-infraspinatus
-teres minor
-subscapularis
(SITS)
What deepens the glenoid cavity?
Fibrocartilaginous labrum
What is the weakest part of the articular capsule and why?
- posterior part
- it isn’t supported by any ligaments
Ligaments of the shoulder
- intrinsic ligaments of the capsule
- glenohumeral ligaments
- transverse humeral ligament
- coracohumeral ligament
- coracoacromial arch
Glenohumeral ligaments
- superior
- middle
- inferior (Supraglenoid to neck and lesser tubercle)
Transverse humeral ligament covers what?
Intertubercular groove
Coracohumeral ligament
Strengthens superior part of capsule
What makes up the coracoacromial arch?
- coracoid process
- coracoacromial ligament
- acromion
What is the purpose of the coracoacromial arch?
Prevents superior displacement of humerus
Triangular space borders
- tendon of long head of triceps
- teres minor
- Teres major
What does the triangular space contain?
Circumflex scapular artery
Quadrangular space boundaries
- long head of triceps
- teres major
- teres minor
- lateral head of triceps brachii
What does the quadrangular space contain?
- axillary nerve
- posterior circumflex humeral artery
Triangular interval boundaries
- teres major
- long head of triceps brachii
- lateral head of triceps brachii
What does the triangular interval contain?
- radial nerve
- deep brachial artery
Triangle of auscultation borders
- inferolateral edge of trapezius (lower fibers)
- dorsomedial ledge of latissimus dorsi
- medial border of the scapula
What movement enlarges the triangle of auscultation? And what does this allow for?
Crossing the arm in front of the body
- causes the intercostal spaces 6 and 7 to become subcutaneous
- allowing for access to respiratory sounds
The arterial supply that forms the anastomotic blood supply to the scapular region are branches of?
Subclavian artery or axillary artery (once it continues past the 1st rib)
Subclavian artery branches off what on the right vs left?
Right: brachiocephalic trunk
Left: aortic arch
What are the parts of the subclavian artery?
1) from origin to medial border of anterior scalene muscle
2) portion situated behind the anterior scalene
3) from anterior scalene’s lateral border to the outer border of the 1st rib
What are the branches of the subclavian artery?
- vertebral artery
- internal thoracic artery
- thyrocervical trunk
- dorsal scapular artery
What does the vertebral artery supply blood to?
Central nervous system
Where is the vertebral artery located?
- in the transverse foraminae of cervical vertebrae
- identified in the floor of the suboccipital triangle
Internal thoracic artery supplies blood to?
The diaphragm
What does internal thoracic artery anastomose with?
Intercostal arteries
What does the thyrocervical trunk branch into?
- inferior thyroid artery
- suprascapular artery
- transverse cervical artery
- superficial scapular artery
Where does the dorsal scapular artery arise from?
- the 3rd part of subclavian artery
- may also arise as a branch of the thyrocervical trunk (then it is named transverse cervical artery)
Axillary artery
-lateral extension of the subclavian artery past the lateral border of the 1st rib
3 parts of the axillary artery
1) lateral border of 1st rib to medial border of pectoralis minor
2) portions situated posterior to pectoralis minor
3) from pectoralis minor’s lateral border to the inferior border of teres major where it becomes the brachial artery
Main branches of the axillary artery are:
- thoracoacromial trunk
- lateral thoracic artery
- subscapular artery
- anterior circumflex humeral artery
- posterior circumflex humeral artery
Thoracoacromial trunk comes off?
The 2nd part of axillary artery
What are the branches of the thoracoacromial trunk?
- clavicular
- acromial
- deltoid
- pectoral
Lateral thoracic artery
- Large in females
- lateral mammary branches to the mammary gland
Subscapular artery comes off?
- the axillary artery (usually 2nd part)
- largest branch
What does subscapular artery branch into?
Circumflex scapular artery thru the triangular space
-continues as the thoracodorsal artery
Where does the anterior circumflex humeral artery come from?
-the lateral side of the axillary artery (2nd to 3rd part)
Where does the posterior circumflex humeral artery come from?
-3rd part posteriorly and goes around the posterior side of humerus thru quadrangular space to Ana Sato Mose with anterior circumflex humeral artery
Which arteries are involved in the scapular anastomosis?
- dorsal scapular
- suprascapular
- subscapular
- circumflex scapular
- branches of intercostal arteries
Where do intercostal arteries come from?
The descending aorta
The anastomosis around the head of the humerus involves?
The anterior and posterior circumflex humeral arteries
Where do the nodes of the axilla carry lymph?
From upper extremity, back, and anterior surface of thorax and abdomen down to umbilicus
What groups are the lymph nodes of the axilla divided into?
- brachial or lateral
- subscapular or posterior
- pectoral or anterior
How does lymphatic drainage enter the venous system?
Thru thoracic duct
What can alter the flow pattern of lymphatic drainage?
Blockage!
-spread of metastatic cells takes place in this fashion
Which muscles receive some branches from ventral rami and spinal accessory nerve?
- trapezius
- sternocleidomastoid
Winged scapula-cause and symptoms
- damage to the long thoracic nerve
- results in paralysis of serratus anterior
- inability to abduct the arm above the horizontal or push with the arm
- scapula is limited in superior rotation
Damage to axillary nerve results in:
- atrophy of deltoid muscle
- pt is unable to maintain abduction of arm against resistance
- roundness of shoulder is absent
Damag to thoracodorsal nerve
- paralysis of latissimus dorsi
- lats are unable to pull body toward humerus (in a closed chain action like pull-ups)
Rotator cuff importance
Provides the main dynamic stability to glenohumeral joint
The weakest support dynamically is when the rotator cuff is in what position? Why?
- inferior
- lack of supporting tendons
What tendon reinforces the superior aspect of the glenohumeral joint?
Supraspinatus tendon
What tendon supports the posterior aspect of the GH joint?
Tendons of infraspinatus and teres minor
What joint supports the anterior aspect of the GH joint?
Tendon of the subscapularis