Nerves Flashcards
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Musculocutaneous nerve arises from which roots
C5-C7
Motor innervation of musculocutaneous
All muscles of the anterior compartment of arm. Biceps brachi, coracobrachialis, brachialis.
Note: all the nuscless in the anterior compartment of arm are flexors
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Sensory innervation of musculocutaneous nerve
Lateral cutaneous nerve of forearm
Provides innervvation to the lateral aspect of the forearm
Lesion of musculocutaneous nerve causes what?
Loss of sensation at the lateral aspect of forearm
Weakness of elbow flexion and forearm supination
Motor innervation of axillary nerve
Deltoid and teres minor
Sensory innervation is of axillary nerve
Superiolateral aspect of arm
Course of axillary nerve
Passes through the quadrangular space with the posterior circumflex humeral artery
How is It injured..axillary nerve
Fracture of the axillary neck of the humerus
What roots does the axillary nerve arise from
5, 6
Sensory branch if axillary nerve?
Superior lateral brachial cutaneous nerve
What are the roots of the radial nerve
C5-T1
Motor innervation of radial nerve
All extensor muscles of arm and forearm
Which muscles are supplied by the radial nerve in the arm
Triceps brachi
What does the radial nerve innervate in the forearm
10 extensors, 5 of which originate from lateral epicondyle(common extensor tendon)
Which of the 5 extenders originate from the lateral epicondyle
Extensor carpi radialis brevis Extensor digitorium Extensor digit minimizes Extensor carpi ulnaris Anconeus
Sensory innervation of radial nerve
Posterior aspect of arm and forearm
Lesions of the radial nerve injuries?
Mid shaft injuries of the humerus
Pressure of badly crutches
Lesion of the radial nerve results in
Wrist drop (Saturday night palsy or honeymoon palsy)
Due to the fact that wrist and fingers cannot extend at metacarpophalangeal joints. Extensors paralyzed due to denervation. Wrist remains partially flexed due to opposing action of flexors in forearm
Brachioradialis and supinator paralysed
Sensory innervation and damage of radial nerve
Posterior surface of lower arm, lateral dorsum of hand, dorsal surface of roots of lateral 3 and 1/2 fingers
