Upper limb / axilla Flashcards
Which muscle group (and muscles) does the musculocuaenous nerve supply?
Root
Flexor compartment of the arm
Coracobrachialis, biceps brachi and brachialis
C5/6/7
What does radial nerve supply?
Roots
All extensor muscles of the arm and forearm, all posterior skin of arm / forearm / hand
C 5/6/7/8/ T1
What does the axillary nerve supply?
Roots
Deltoid, teres minor, skin over lower part of deltiod (regimental patch)
C5–6
What does the median nerve supply
Roots
All flexor muscles of the forearm
(except for the flexor carpi ulnaris and the medial half of the flexor digitorum profundus)
The thenar muscles (flexor pollicis brevis, abductor pollicis brevis, opponens pollicis) and the lateral two lumbricals
Skin over lateral palm and lateral 3 1/2 digits including nail beds
C5/6/7/8, T1
What does the ulnar nerve supply?
Roots
flexor carpi ulnaris and the medial half of the flexor digitorum profundus
Majority of intrinsic muscles of the hand
Skin over palm and medial 1 1/2 digits
C8.- T1
Upper brachial plexus injury presentation
Erbs palsy
Arm hangs by side, rotated medially, forearm extended and pronated
Loss of sensation in the arm and paralysis / atrophy of deltoid / biceps & brachialis muscle
Lower brachial plexus injury presentation
Klumpke’s plasy
Paralysis / atrophy of intrinsic muscles of the hand + flexors of wrist / hand
Subscapularis
Action
Nerve supply
GH medial rotation
Upper and lowr subscapular nerve (posterior cord)
Teres major
Action
Nerve supply
ADDuction and medial rotation of GH joint, and extension of shoulder
Lower subscapular nerve
Lat Dorsi
Action
Nerve supply
ADDuction and medial rotation of GH joint and extension of shoulder
Thoracodorsal nerve
Trapezius
Action - upper / middle / lower
Nerve supply
Upper elevates the scapula
Middle retracts the scapula
Lower depresses and laterally rotates the scapula
Accessory nerve
Pectoralis major
Action
Nerve supply
ADDuction of GH joint
Medial rotation
Flexion of extended arm
Extension of flexed arm
Lateral and medial pectoral nerves
Pectoralis minor
Action
Nerve supply
Stabilises the scapula on the thorax
Lateral and medial pectoral nerves
Deltoid (Ant / Post/ Middle)
Action
Nerve supply
ANTERIOR
Flexes the humerus at the GH
Medially rotates the humerus at GH
MIDDLE
ABDucts at GH joint
Attaches limb to pectoral girdle
POSTERIOR
Extends the humerus at GH
Laterally rotates the humerus at GH
Axillary nerve
Presentation of clavicle #
Drooped shoulder, medially rotated
Ligaments that re-inforce the AC joint
Coracoclavicular ligaments (Trapezoid and conoid)
Intrinsice ligament of AC joint
Acromioclavicular ligament
Movements of the AC joint
Retraction and protraction of the scapula
Elevation of the arm via rotation of the scapula
Ligaments forming the Sternoclavicular joint
Interclavicular ligament
Anterior stenoclavicular ligament
Costoclavicular ligament
What do ALL rotator muscles do?
ALL stabalise the GH joint
Rotator cuff muscle position & movements:
S
I
T
S
Supraspinatius - posterior, first 15 degrees of ABDuction
Infraspinatus - posterior, lateral rotation
Teres minor - posterior, lateral rotation
Subscapularis - anterior, medial rotation
ABDuction of the shoulder
First 15 degrees
Up to 90 degrees
Beyond here
Supraspinatus
Deltoid
Trapezius
Test for supraspinatus injury on exam
Empty Can Test: Position the patient with arms elevated to 90 degrees in the scapular plane, with the elbow extended, and full medial rotation and pronation of the forearm with thumbs pointing downwards. Ask the patient to resist the downward force being applied to the forearm. Test is positive is patient has pain or weakness.
Test for infraspinatus + teres minor injury on exam
Infraspinatus Test: Position the patient with the arm fully adducted, with the elbow flexed to 90 degrees. Ask the patient to resist the medially directed force to the arm. Test is positive if patient has pain or weakness.
Test for supraspinatus on exam
Lift off test (behind back)
Biceps brachii
Action
Nerve supply
Flex shoulder and elbow
Supinates
forearm
Musculocutaneous nerve
Brachialis
Action
Nerve supply
Flexes the elbow
Musculocutaneous nerve
Coracobrachilais
Action
Nerve supply
Flexes the shoulder
Musculocutaneous nerve
Biceps tendon reflex tests which ROOT?
C6
What does the Musculocutaneous nerve become?
Lateral cutaneous nerve of the forearm
Triceps brachii
Action
Nerve supply
Extends the forearm at the elbow joint
Radial nerve
What prevents superior dislocation of the humerus
Coracoacromial arch
How does the radial nerve lie along the humerus
In the spiral groove in direct contact with the bone, with the profunda brachii artery
Veins of the arm and position
Connected by what at the cubital fossa?
Cephalic - laterally
Basilic - medially
Median cubital vein
Where is the axillary nerve at risk in terms of a #
Surgical next of humerus
Where is the ulnar nerve
Medial epicondyle
Ligaments of the elbow
Collateral (lie laterally)
& annular ligament
Aetiology of the ‘pulled elbow’
Dislocation of the. radial head from the annular ligament in children
Muscles involved in supination
Biceps brachii
Brachioradialis
Supinator
Muscles involved in pronation
Prontator quadratus
Prontator teres
Major contents of the cubital fossa
Medial -> lateral
Median cutaenous nerve of the forearm
median nerve
brachial artery
biceps tendon
radial nerve
Medial and lateral wall of the ACF
Pronator teres
Brachioradialis
Flexors of the forearm originate…
from the medial epicondyle
Extensors of the forearm originate…
from the lateral epicondyle
Tennis elbow
Epicondylitis of the lateral epicondlye (extensors)
tEnnis elbow
Golf elbow
Epicondylitis of the medial epicondlye (extensors)
golF elbow
What is at risk in a supracondylar #
Occlusions of brachial artery
also risk to median, ulnar and radial nerves
Why is the radius more likely to be # in the wrist?
Ulnar doesn’t articulate with the carpals to radius takes the full force
Which carpal bones does the radius articulate with?
Scaphoid and lunate
3 layers of anterior forearm muscles
How many in each layer?
Superficial - 4
Intermediate - 1
Deep - 3
Which muscles lie in the superficial layer of the ant. forearm
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
Which muscle lies in the intermediate layer of the ant. forearm
And where does it’s tendons insert
Flexor digitorum superficialis
Pass deep to the flexor retinaculum and insert onto the middle phalanges
Which muscles lie in the deep layer of the ant. forearm
Flexor digitorum profundus
Flexor pollicis longus
Pronator quadratus S
Plamaris longus is the surface marker for what at the wrist?
Median nerve
Surface marking for radial artery at the wrist
Lateral to the flexor carpi radialis tendon
Where do the ular and median nerve lie in the anterior forearm
Intermediate/deep layer, between FDS and FDP
Which muscle lies in the superficial layer of the ant. wrist
Either side of the FDS
Which layer of the anterior forearm does the radial nerve. and artery sit?
Superficial layer
Branches of the brachial artery (2)
Radial and ulnar artery
Branches of the ulnar artery (2)
Ulnar collateral
Common interosseous artery
Branches of the common interosseous artery
Ant. and post.
Where are the NV structures at risk in the lower arm
ACF and radiocarpal joint (wrist)
What nerve supplies the posterior forearm
Posterior interoessous nerve
Colles # =
following a fall on the hand
Involves the distal radius
Often presents as a dinner fork deformity
Borders of the anatomical snuff box
Medial
Lateral
Proximal
Floor
Roof
Tendon of EPL
Tendon of abductor PL and EPB
Styloid process of radius
Carpal bones, scaphoid and trapezium
Skin
Superficial muscles of the posterior forearm
Extensor carpi radialis brevis
Extensor digitorum
Extensor carpi ulnaris
Extensor digiti minimi
Brachioradialis
Extensor carp radialis longus
Deep muscles of the posterior forearm
Supinator
APL
EPB
EPL
Extensor indicis
Carpal bones of the hand order
Radial -> ulnar (1st layer)
2nd layer
Scaphoid
Lunate
Triquetral
Pisiform
Trapeszium (back at the thumb)
Capitate
Hamate
What forms the roof of the carpal tunnel?
Flexor retinaculum
3 thenar muscles?
Abductor pollicis
Flexor pollicis
Opponens pollicis
Which nerve supplies the thenar muscles?
hypothenar…
Median nerve
Ulnar
3 hypothenar muscles?
Abductor digiti minimi
Flexor digiti minimi
Opponens digiti minimi
Fracture of rib one may compromise which artery?
Distal subclavian
Anterior dislocation of the humeral head may compress what artery?
Axillary artery
Laceration of the wrist puts which nerves at risk?
Median and ulner
Medial epicondyle # puts which nerve at risk?
Ulnar nerve
Which groups of muscles provide the ‘power grip’
Extrinsic forearm muscles
Which muscles provide the pinch grip
Intrinsic muscles
Actions of the lumbricals
Flex the MP
Extend the IP
Actions of the interossei
Flex the MP
Extend the IP
What supplies adductor pollicis
Ulnar nerve
Which muscles make up the thenar muscles?
And what nerve supplies them?
adductor pollicis, abductor pollicis brevis, flexor pollicis brevis and opponens pollicis.
What is froment’s test
The Froment’s sign test is performed to determine the presence of an ulnar nerve injury. Bending the thumb when pinching a piece of paper is a sign of an ulnar nerve injury.
Where does the FDS tendons split?
As it inserts on the middle phalange
Where doe the tendons of FDP insert?
Distal phalanges
Why is paraesthesia of the palm not found in true carpal tunnel?
Nerve that supplies the lateral palm is a branch that runs superior to the flexor retinaculum §
Where is musculocutaenous nerve commonly injured?
Stab wound in axilla
Motor and sensory loss in musculocutaenous nerve injury
Motor loss: Weakness of flexion and supination of the forearm, weakness of arm flexion
Sensory loss: Lateral aspect of forearm
What is the flexor retinaculum attached to laterally?
medially
Scaphoid & trapezium
Pisiform and hook of hamate
Attachments of extensor retinaculum:
Medially
Laterally
Pisiform and triquestrum
Anterolateral to the radius above the styloid
