Brachial Plexus Injuries

Question 1

flattened deltoid
loss of arm abduction > 15 deg
loss of sensation over deltoid muscle and lateral arm

Answer 1

C5-C6: axillary nerve

fractured surgical neck of humerus
anterior dislocation of humerus

Question 2

loss of forearm flexion and supination

loss of sensation over lateral forearm

Answer 2

C5-C7: Musculocutaneous n

upper trunk compression

Question 3

wrist drop
loss of elbow/wrist/finger extension
decreased grip strength
loss of sensation over posterior arm/forearm and dorsal hand

Answer 3

C5-T1: radial n

compression of the axilla (crutches or sleeping with arm over chair)

mid-shaft humerus fracture
repetitive pronation/supination of forearm due to screwdriver use (“finger drop”)

Question 4

ape hand and pope's blessing
loss of wrist flexion 
loss of flexion of lateral fingers 
loss of thumb opposition
lumbricals of 2nd and 3rd digits 
loss of sensation over thenar eminence

Answer 4

C5-T1: Median n

supracondylar fracture of humerus (proximal lesion)

carpal tunnel syndrome

Question 5

claw hand
radial deviation of wrist on flexion
Loss of wrist flexion, flexion of medial fingers
loss of abduction and adduction of fingers
loss of sensation over medial 1 1/2 fingers including hypothenar eminence

Answer 5

C8-T1: ulnar n

proximal lesion: fracture of medial epicondyle of humerus (funny bone)

distal lesion: fractured hook of hamate (distal lesion)

Question 6

arm…medially rotated, extended and pronated

Answer 6

Waiters tip/erb’s palsy: C5-C6, upper trunk

Question 7

total claw hand!

Answer 7

klumpke: C8-T1, lower trunk

Question 8

Arm abduction 0-15 deg

Answer 8

supraspinatus m. - suprascapular n

Question 9

Arm abduction 15- 50 deg

Answer 9

deltoid m. - axillar n.

Question 10

Arm abduction above 90 deg

Answer 10

trapezius m - accessory n.

Question 11

Arm abduction beyond 100 deg

Answer 11

serratus anterior m. - long thoracic n.

Question 12

Rotator cuff muscles 1

Answer 12

SItS:
Supraspinatus m - suprascapular n.

(abduction)

Question 13

Rotator cuff muscles 2

Answer 13

SItS:

infraspinatus m. - external rotation - suprascapular n.

Question 14

Rotator cuff muscles 3

Answer 14

SItS:

teres minor m. - external rotation - axillary n.

Question 15

Rotator cuff muscles 4

Answer 15

SItS:

subscapularis m. - internal rotation and adduction - upper/lower subscapular n. (c5-c6)