Upper extremity Flashcards
Injury to axillary nerve
- sensory impairment to lateral surface of shoulder
- shoulder weakness, especially with abduction
Supraspinatus
- Action
- abduction of shoulder
- Innervation
- suprascapular nerve

Dorsal scapular nerve (C5)
rhomboid major/minor and levator scapulae muscle
Teres Minor
- Action
- laterally rotates shoulder
- Innervation
- Axillary nerve

Extensor digiti minimi
- Action
- extends wrist and 5th finger
- Innervation
- radial nerve

Pronator quadratus
- Action
- pronates forearm
- Innervation
- median nerve

Pronator Teres
- Action
- Pronates and flexes forearm
- Innervation
- median nerve

Extensor carpi ulnaris
- Action
- extends and adducts wrist
- Innervation
- radial nerve

Deep muscles of the posterior forearm
- Abductor pollicis longus
- extensor pollicis longus
- extensor pollicis brevis
- extensor indicis
**all extend and all innervated by radial nerve
Triceps Brachii
- Action
- extends elbow joint
- Innervation
- Radial nerve

Muscles innervated by musculocutaneous nerve
- Biceps brachii
- brachialis
- coracobrachialis
Extensor digitorum
- Action
- extend wrist and medial 4 fingers
- Innervation
- radial nerve

Levator Scapulae
- Action
- Elevates scapula
- Innervation
- Dorsal scapular nerve

Thoracodorsal Nerve
(C7-C8)
Latissimus dorsi muscle
pectoralis major
- Action:
- adducts and medially rotates shoulder joing
- innervation:
- lateral and medial pectoral nerve

Subscapularis
- Action
- Medially rotates and adducts shoulder joint
- Innervation
- superior and inferior subscapular nerves

Extensor pollicis brevis
- Action
- extends wrist and thumb
- Innervation
- radial nerve

scapula
- overlays the 2nd-7th rips
- lateral border is thickest
- glenoid cavity articulates with head of humerous at glenohumeral joint

Latissimus dorsi
- Action
- extends, adducts and medially rotates shoulder
- Innervation
- thoracodorsal nerve

Rotator cuff
- Supraspinatus
- Infraspinatus
- Teres Minor
- Subscapularis
Extensor indicis
- Action
- extends wrist and 2nd finger
- Innervation
- radial nerve

Teres Major
- Action
- adducts and medially rotates shoulder
- Innervation
- Inferior subscapular nerve

Brachialis
- Action
- flexes elbow
- Innervation
- musculocutaneous nerve

axio-appendicular muscles
attach to the ribs, sternum, and vertebrae. Suport and move pectoral girdle
Arterial supply to upper extremity
- sublcavian artery
- axillary artery
- brachial artery
- four terminal branches
Medial Brachial cutaneous nerve
(C8-T1)
Sensory to the medial side of the arm
Brachioradialis
- Action
- weak flexion of elbow
- Innervation
- radial nerve

Pectoral girdle
- scapulae
- clavicles
- manubrium of sternum
- support and movement provided by the axio-appendicular muscles
Flexor Carpi Radialis
- Action
- Flexes and abducts hand at wrist
- Innervation
- Median nerve

humerus
- largest bone in upper limb
- radial groove for the radial nerve and profunda brachii artery
Musculocutaneous nerve
- pierces coracobrachialis muscle
- innervates brachialis and biceps brachii
- continues as sensory to lateral cutaneous nerve of the forearm
- Injury:
- sensory impairment to lateral surface of forearm
- paralysis of coracobrachialis, biceps, brachialis
Nerve to Subclavius
(Superior trunk/ C5)
subclavius muscle
Trapezius
- Action
- lifts and retracts scapula
- Innervation
- spinal accessory nerve (CNXI)

Rhomboid Minor
Rhomboid Major
- Action
- holds scapula to thoracic wall
- innervation
- dorsal scapular nerve

Supericial muscles of anterior forearm
- Pronator Teres
- Flexor Carpi Radialis
- palmaris longus
- flexor carpi ulnaris
Extensor carpi radialis brevis
- Action
- extend and abduct wrist
- innervation
- radial nerve

Superior subscapular nerve
(C5-C6)
subscapularis muscle
Palmaris Longus
- Action
- Flexes hand at wrist
- Innervation
- Median nerve

Lateral pectoral nerve
(C5-C7)
Pectoralis major muscle
Deltoid
- Action
- abducts shoulder joint
- innervation
- axillary nerve

Extensor carpi radialis longus
- Action
- extend and abduct wrist
- Innervation
- radial nerve

How median nerve innervates hand
- abducts thumb
- opposes thumb
- flexes thumb
- flexes metacarpophalangeal joints of the 2-4th fingers
- Injury
- sensory impairment to anterior thumb, palmer surface, anterior first 2.5 fingers and posterior joint of first 2.5 fingers
- loss of thumb opposition, decreased abduction of thumb, loss of flexion of proximal and distal interphalangeal joings
- “pope’s blessing” or “ape hand”
Inferior subscapular nerve
(C5-C6)
Subscapularis and teres major muscles
Biceps brachii
- Action
- supinates forearm and flexes elbow
- Innervation
- musculocutaneous nerve

Radius
- lateral to ulna and shorter
- shaft gradually enlarges as it passes distally
- with pronation of forearm, radius crosses ulna
Axillary artery
- lateral margin of 1st rib to inferior border of the teres major
Medial Pectoral nerve
(C8-T1)
Pectoralis major and minor muscles
Brachial artery
- Inferior border of the teres major muscle to the distal portion of the cubital fossa
Clavicle
- connects upper limb to axial skeleton
- sternal end touches sternum at sternoclavicular joint
- acromoial end touches the acromion of the scapula at acromioclavicular joint

Abductor pollicis longus
- Action
- extends wrist and abducts thumb
- innervation
- radial nerve

Flexor digitorum superficialis
- Action
- flexes wrist and proximal phalanges
- Innervation
- Median nerve

How the Ulnar nerve innervates hand
- adducts thumb
- abducts 5th finger
- flexes 5th finger
- opposes 5th finger towards thumb
- Injury
- Sensory impairment of medial surface of hand/palm and medial 1.5 fingers
- loss of flexionat 4th and 5th fingers, loss of thumb adduction, loss ability to oppose and abduct 5th finger
- “claw hand”
Infraspinatus
- Action
- laterally rotates shoulder
- innervation
- Suprascapular nerve

Intermediate and deep muscles of the anterior forearm
- flexor digitorum superficialis
- flexor digitorum profundus
- flexor pollicis longus
- pronator quadratus
Flexor pollicis longus
- Action
- flexes wrist and thumb
- Innervation
- median nerve

ulna
- medial
- stabilizing bone of the forearm
- shaft is thick but tapers distally
Flexor digitorum profundus
- Action
- flexes wrist and phalanges 2-5
- Innervation
- Median nerve and ulnar nerve

Medial antebrachial cutaneous nerve
(C8-T1)
Sensory to the medial side of the forearm
Pectoralis Minor
- Action
- stabilizes scapula
- Innervation
- medial pectoral nerve
Injury to radial nerve
- sensory impairment to posterior surface of forearm, posterior thumb and first 2.5 fingers
- paralysis of triceps, brachioradialis, supinator, extensors of the wrist and fingers
- “wrist drop”
Extensor pollicis longus
- Action
- extends wrist and thumb
- Innervation
- radial nerve

Coracobrachialis
- Action
- flex and adduct shoulder
- Innervation
- musculocutaneous nerve

Long thoracic nerve (C5-C6)
serratus anterior muscle
*Injury causes paralysis of serratus anterior and medial border of scapula proturdes away from body
Superficial muscles of the posterior forearm
- Brachioradialis
- extensor carpi radialis longus
- extensor carpi radialis brevis
- extensor digitorum
- extensor digiti minimi
- extensor carpi ulnaris
**All are innervated by the radial nerve
Flexor carpi ulnaris
- Action
- Flexes and adducts hand at wrist
- Innervation
- Ulnar nerve

Suprascapular nerve
(superior trunk/C5-C6)
supraspinatus and infraspinatus muscles
Serratus Anterior
- Action
- holds scapula to thoracic wall
- Innervation
- long thoracic nerve (LTN)
