MSK Upper Extremity nerves
Damage to the axillary nerve presents after what with what?
Fracture surgical neck of humerus
Anterior dislocation of humerus
Flattened deltoid/loss of abduction >15 degrees
loss of sensation over deltoid and lateral arm
Damage to musculocutaneous nerve presents how?
Upper trunk compression (C5-C7)
Loss of forearm flexion/supination
Loss of sensation over lateral forearm
Damage to the radial nerve presents how?
Mid shaft humerus fracture
compress of axilla(Saturday night palsy)
decrease grip strength
loss of senstation over posterior arm/forearm dosal hand
Median nerve damage cause and findings?
Supracondylar fracture or humerus
Carpal tunnel or wrist laceration
wrist flexion, thumb, 2,3 digit
Loss of sensation over 1,2,3 and 1/2 4 digit
Tinel sign +
Ulnar nerve damage cause and findings?
Fracture of medial epicondyle
Fracture hook of hamate
Claw hand/radial deviation of wrist with flexion
Loss of sensation over the 1/2 4 and 5 digit
Recurrent branch of median nerve
Superficial laceration of palm
loss of thenar muscle group
NO SENSATION loss
Brachial plexus is made up of which nerve roots?
What is the composition of the long thoracic nerve?
draw the brachial plexus
What is Erb palsy(waiter's tip)?
UPPER roots C5-C6 (traction injury)
Causes: Infants traction neck
Function Look at the picture
abduction/Lateral rotation/ flexion/supination
What is the Klumpke palsy?
Klumpke monkey (Lower traction injury C8-T1)
Cause: Upward force on delivery(grapping a tree)
Muscle: Intrinsic hands muscles
Presents: Total claw hand
Thoracic Outlet Syndrome(TOS)
Compression of lower trunk and subclavian vessels
Cause: Cervical rib/Pancoast tumor
Similar to Klumpke
Nerve: Long thoracic (C5-C7)
Cause: Axillary node dissection /Stab
Muscle: Serratus anterior
Function: unable to anchor scapula to thoracic cage
The more distal the lesion the worse it is
the more proximal the better because more nerve fibers contribute to the action of the muscle
Where are the thenar and hypothenar eminence on the hand?
Thenar is lateral
Hypothenar is medial
What muscles compose the thenar eminece?
OAF (pollicis means thumb)
Abductor pollicis brevis
Flexor pollicis brevis
What muscles make up the hypothenar emience?
OAF (digiti minimi means pinky finger)
Opponens digiti minimi
Abductor digiti minimi
Flexor digit minimi
What muscles adduct the fingers and which muscles abduct the hand?
DAB = Dorsal interossei - ABduct
PAD = Palmar interossei - ADDuct
What do the lumbrical muscles do in the hand?
flex at MCP