Upper Extremity Nerves EC Flashcards
Axillary nerve (roots, typical injury, sign, muscles innervated)
C5-6
Fractures surgical neck of humerus
Dislocation of humeral head
Atrophied deltoid
Deltoid, Triceps longhead, teres minor
Radial nerve (roots, typical injury, sign, muscles innervated)
C5-T1
Fractures midshaft humerus
“Saturday Night palsy”/Incorrect use of crutches
Wrist drop
BEST: Brachioradialis, Extensors, Supinator, Triceps
Median nerve (roots, typical injury, sign, muscles innervated)
C5-T1
Fracture of supracondylar humerus
Impaired opposition of thumb, lateral finger flexion, and wrist flexion
“Ape hand” and “Pope’s blessing”
Forearm: flexors (minus carpi ulnaris and ulnar 1/2 of digitorum profundus)
Hand: Thenar muscles and 1st 2 lumbricals (“MED-LOAF”)
Ulnar nerve (roots, typical injury, sign, muscles innervated)
C8, T1
Fracture of medial epicondyle of humerus (funny bone)
Impaired medial finger flexion and wrist flexion
Radial deviation of wrist upon flexion
Forearm: flexor carpi ulnaris + 1/2 digitorum profundus
Hand: all but MED-LOAF
Musculocutaneous nerve (roots, typical injury, sign, muscles innervated)
C5-C7
Upper trunk compression
Impaired flexion at elbow
BBC - Brachialis, Biceps, Coracobrachialis
Limb adducted, medially rotated, and forearm pronated (lesion and common cause)
Damage to C5-C6 roots (Erbs palsy)
Often seen in infants following trauma during delivery
Atrophy of the thenar and hypothenar eminences, Atrophy of the interosseous muscles, Sensory deficits on the medial side of the forearm and hand, Disappearance of the radial pulse upon moving head toward ipsilateral side
Embryologic defect in C8-T1 or a cervical rib compressing subclavian artery and inferior trunk
Klumpke’s palsy/Thoracic outlet syndrome
Inability to extend 4th and 5th digits when trying to open hand
Ulnar claw
Distal ulnar nerve lesion (ie hook of hamate) leads to loss of medial lumbrical function
2nd and 3rd digits clawed upon attempted finger extension.
Median claw
Carpel tunnel or dislocated lunate
Distal median nerve lesion leads to loss of lateral lumbrical function
Loss of function of all lumbricals, finger flexers. Clawing of all digits
Klumpke’s total claw
C8-T1 lesion
What does the dorsal scapular nerve innervate?
Rhomboids
What does the long thoracic nerve innervate?
Serratus anteroir
What does the suprascapular nerve innervate?
Supraspinatus and Infraspinatus
What does the lateral pectoral nerve innervate?
Pectoralis major
What does the medial pectoral nerve innervate?
Pectoralis major and minor