Upper limb anatomy Flashcards
Where are the two articular facets on the clavicle?
What sits on the inferior lateral third of the clavicle, and what attaches here?
One facet medially for sternum
One facet laterally for acromium
On inferior surface = Conoid tubercle where conoid ligament attaches, and trapezoid line were trapezoid ligament attaches
- Both from coracoid process
- Both together make up the coracoclavicular ligament
Describe the structure of the scapula?
Lateral part marked by glenoid cavity
Above this is supraglenoid tubercle = long head of biceps brachii
Below this is infraglenoid tubercle = long head of triceps brachii
From glenoid cavity a prominent spine passes inferomedially on posterior scapula = supraspinous fossa and infraspinous fossa
Acromium is anterolateral projection of the spine
What three joints make up the shoulder joint?
And what ligaments strengthen each part?
Sternoclavicular joint:
Anterior sternoclavicular ligament, interclavicular ligament and costoclavicular ligament
ACJ:
Reinforced by acromioclavicular ligament
Trapezoid ligament and conoid ligament = coracoclavicular ligament
Glenohumeral joint
What is glenoid labrum, and what is it continuous with superiorly?
What are the three areas it is thickened?
Fibrocartilagenous ring, attached to free edge of glenoid cavity
Superiorly it is continuous with tendons of long head of biceps
- Anterosuperior to form superior, middle and inferior glenohumeral ligaments - attach to lesser tubercle
- Superiorly between coracoid process and greater tubercle = coracohumeral ligament
- Between greater and lesser tubercle = transverse humeral ligament = holds long head of biceps in place in the intertubercular groove
Trapezius?
Elevates scapula and rotates it in humeral abduction
- middle fibres retract scapula
- lower fibres depress scapula
Origin = superior nuchal line, spinous processes of C7-T12
Insertion = Superior edge of scapula spine, acromium and lateral third of clavicle
Accessory nerve
Deltoid?
Major abductor of shoulder once past 15-degrees
Origin = Inferior crest of scapular spine, lateral acromium and lateral third of clavicle
Insertion = deltoid tuberosity of humerus
Axillary nerve
Levator scapulae?
Action = elevates scapula
Origin = transverse process of C1/2 + posterior tubercle of C3/4
Insertion = Medial border of scapula to root of spine
Dorsal scapular nerve
Rhomboid minor and major?
Both elevate and retract scapula
Both Dorsal scapular nerve
Both insert into medial scapular to the root of spine
Minor origin = lower end of ligamentum nuchae + spinous process of C7 to T1
Major origin = spinous process of T2-T5
Supraspinatus muscle?
First 15-degrees abduction
Origin = medial 2/3rds supraspinous fossa of scapula
Insertion = upper facet of greater tubercle of humerus
Suprascapular nerve
Infraspinatus muscle?
Lateral rotation of arm at glenohumeral joint
Origin = medial 2/3rds of infraspinous fossa
Insertion = middle facet of greater tubercle of humerus
Suprascapular nerve
Teres minor muscle?
Lateral rotation of arm at GHJ
Origin = upper 2/3rds of flattened strip of bone on posterior scapula
Insertion = Inferior facet on greater tubercle of humerus
Axillary nerve
Teres major muscle?
Medial rotation of arm and extension
Origin = Inferior angle of posterior scapula
Insertion = medial lip of intertubercular sulcus on anterior humerus
Inferior subscapular nerve
Long head of triceps?
Extends forearm at elbow
Origin = infraglenoid tubercle on scapula
Insertion = Common tendon with medial and lateral head attach to olecranon process of ulna
Radial nerve
4 gateways in posterior scapular region?
Quadrangular space
Triangular space
Triangular interval
Suprascapular foramen
Borders and contents of the 4 gateways in the posterior scapular region?
- Suprascapular foramen = superior transverse scapular ligament passing over suprascapular notch
- Suprascapular nerve passes through it
- Suprascapular artery and vein pass immediately superior to the ligament - Triangular space = medial margin of long head of triceps, inferior teres minor and superior teres major
- Circumflex scapular artery and vein - Triangular interval = Medial humerus, lateral long head of triceps and inferior teres major
- Radial nerve, profunda brachii artery + veins - Quadrangular space = Humerus, long head of triceps, subscapularis superiorly and teres major inferiorly
- axillary nerve
- posterior circumflex artery
Borders of the axilla?
Lateral = Humeral head Medial = chest wall and serratus anterior Anterior = lateral border of pec major Posterior = subscapularis, teres major and lats
Fascia = clavipectoral fascia
What axillary fascia do you divide in an axillary node clearance?
Clavipectoral fascia
What makes up the axillary inlet and what passes through?
Medially = lateral border of rib 1 Anterior = posterior clavicle Posterior = superior scapula
Contents = when subclavian artery turns into axillary artery
Vice versa for axillary vein
Pec Major?
Flexes, adducts and medially rotates arm
Origin = medial 2/3rds of the clavicle, manubriosternal joint and first 7 costal cartilages
Insertion = Lateral lip of intertubercular sulcus
Lateral + medial pectoral nerve
Pec minor?
Pulls tip of shoulder down and protracts scapula
Origin = ribs 3-5 Insertion = coracoid process
Medial pectoral
Subclavius?
Pulls clavicle medial to stabilise SCJ + pulls tip fo shoulder down
Origin = first rib Insertion = groove in inferior surface of middle third of clavicle
Nerve to subclavius
Serratus anterior?
Protracts and rotates scapula
Origin = lateral surface of upper 8/9 ribs Insertion = medial border of scapula
Innervation = long thoracic nerve
Subscapularis?
Medially rotates humerus
Origin = Medial 2/3rds of sub scapular fossa Insertion = lesser tubercle of humerus
Upper and lower scapular nerves
Latissimus dorsi?
Adducts, medially rotates and extends the arm
Origin = spinous process of T1-T6, lower 3/4 ribs ad iliac crest Insertion = Floor of inter tubercular sulcus
thoracodorsal nerve
Contents of the axilla?
3 nerves = long thoracic, thoracodorsal + intercostobrachial
Artery = axillary Vein = axillary
LN’s
Axilla: Course of long thoracic nerve + pathology
C5-C7
Passes anterior to scalenus posterior, posterior to clavicle but anterior to rib 1.
Lies medial on chest and supplies serrates anterior
Passes BEHIND brachial plexus
Risk in axillary surgery = winging of scapula
Axilla: What does thoracodorsal nerve innervate, course and pathology?
Lattisimus dorsi
Arises from posterior cord of brachial plexus. Runs down posterior axillary wall.
At origin it is posterior to sub scapular artery, distally moves anterior to it.
Can be damaged in axillary node clearance as it runs through the axillary nodes
= Fatigue of arm after repetitive use + problematic if going for a lat dorsi flap reconstruction
Axillary vein - boundaries, what forms it, and where does cephalic come from and join?
From lower margin of teres major up to lateral border of first rib - continuation of the basilic vein
Passes through axilla anterior and medial to the artery
Cephalic drains lateral and posterior hand.
In shoulder it passes deep to clavicular head of pec major and pierces clavipectoral fascia to join axillary vein
Axilla: Intercostobrachial nerve - what it is a branch of, what it supplies and how is it injured?
Branch of second intercostal nerve.
Leaves 2nd intercostal space at MAL, then pierces serratus anterior.
Axillary sensation
Axillary node clearance
Axillary LN’s - what are the three levels and what is divided in Pateys mastectomy ?
Level 1 = inferior to pec minor
Level 2 = posterior to pec minor
Level 3 = above pec minor
Level 1+2 in normal LN dissection, occasionally level 3 taken out but rarely.
Axillary artery - boundaries of it and its three parts, course and branches?
Lateral border of first rib to inferior margin of teres major
1st part = above pec minor
- together with axillary vein is enclosed in cords of brachial plexus
2nd part = behind pec minor
- Posterior = posteiror brachial plexus cord + subscapularis, medial is medial cord of brachial plexus (separating artery and vein), anterior = pec major and minor, and lateral is lateral cord of brachial plexus
3rd part = below pec minor
- Posterior = subscapularis, teres major and lats
- between the subscapularis and artery is radial and axillary nerve
Branches:
1st part = 1 = superior thoracic
2nd part = 2 = thoracic-acromial and lateral thoracic
3rd part. = 3 = sub scapular, anterior circumflex and posterior circumflex
Where do you insert chest drains ?
5th ICS MAL
Borders:
Anterior edge lat dorsi
Pec major lateral border
Above and below nipple
insertion of each rotator cuff?
Supraspinatus = superior facet on G tubercle
Infraspinatus = middle facet
teres minor = inferior facet
Subscapularis = lesser tubercle of humerus
Where does lateral head of triceps attach?
Liner roughing from surgical neck to deltoid tuberosity on posterior humerus
What runs through the inter tubercular groove, and what holds it there?
Biceps brachii long head tendon
Transverse humeral ligament
Which arteries supply humeral head?
where = risk of….
Anterior and posterior circumflex artery
surgical neck = avascular necrosis, as well as damage to axillary nerve and posteiror circumflex artery
Surgical neck vs anatomical neck of humerus
Surgical neck = below tubercles and head
Anatomical = narrowing just below head
On posterior shaft of humerus what is there a spiral groove for?
Radial nerve
What is the structure of distal humerus?
What articulates / attaches to each bit?
1 condyle = made up of capitulum and trochlea
CAPITAL RADIO
2 epicondyles:
Medial = anterior forearm compartment muscles
Lateral = posterior compartment
3 fossa:
Anterior = Radial fossa superior to capitulum
Anterior = Ulnar fossa superior to trochlea
POSTERIORLY = olecranon fossa, superior to trochlea
Muscles of anterior compartment of arm?
MUSCULOCUTANEOUS NERVE for all
corachobrachialis = flex arm at GHJ origin = Coracoid process of scapula Insertion = Medial humerus midshaft, linear roughening
Biceps brachii = flexor of forearm + supinator
Origin: Long head = supraglenoid tubercle, short head = coracoid process
Insertion = radial tuberosity (medial aspect of radius)
Brachioradialis = flexor of forearm origin = Anterior humerus Insertion = Tuberosity of ulna
Muscle of posterior arm?
RADIAL NERVE
Triceps brachii = extends forearm
Origin: Long head = infraglenoid tubercle. Medial and lateral head = posterior humerus
Insertion = olecranon
Which ligament wraps around head of radius?
Annular ligament of radius
Which ligaments laterally strengthen the fibrous capsule of elbow?
Which muscle inserts posteriorly into fibrous capsule?
Radial collateral = Attaches to lateral epicondyle of humerus > blends with annular ligament of radius > attaches to radial notch of ulnar
Ulnar collateral = three parts
Anterior band - medial epicondyle humerus > medial edge of coronoid process ulna
Posterior band - medial epicondyle humerus > medial olecranon
Transverse = joins the two together
Triceps tendon inserts posteriorly
What forms your cubital fossa?
Brachioradilais laterally
Pronator teres medially
Line between two epicondyles
Major contents of cubital fossa?
Median and radial nerve, brachial artery and vein and tendon of biceps brachii
Where does brachial artery bifurcate?
Apex of cubital fossa
Into radial and ulnar artery
In cubital fossa - where is median nerve vs brachial artery, and how does it leave?
It sits median to brachial artery
Leaves between two heads of pronator teres
What protects the nerve and artery in the cubital fossa?
Bicipital aponeurosis
How does radial nerve leave elbow?
Lies just underneath lip of brachioradialis
Here it splits into superficial and deep
Superficial = forearm Deep = passes between two heads of supinator to posterior compartment of forearm
How does ulnar nerve traverse elbow?
Passes posterior to medial epicondyle
What makes up roof of cubital fossa and what lies here?
what does this structure connect?
What separates this structure from the brachial artery and median nerve.
Superficial skin and fascia
Median cubital vein connect basilic vein medially to the cephalic vein laterally
Bicipital aponeurosis separates them
What muscles attach to the radius?
Upper third = supinator, FDS, FPL
Middle third = pronator teres (oval roughening)
Lower third = pronator quadratus and tendon of supinator longus
What are the three grooves on posterior distal radius for?
- Tendons of extensor carpi L+B
- Tendons of extensor pollicis longus
- Tendons of extensor indicis
What is medial and lateral on distal radius?
what does it have two facets for?
Lateral = styloid process Medial = ulnar notch
Scaphoid and lunate