Upper Extremity Nerve Testing

Question 1

C5 myotome

Answer 1

1. Abduction shoulder

2. Flexion elbow

Question 2

C6 myotome

Answer 2

1. Elbow flexion
2. Wrist extension
3. Shoulder adduction

Question 3

C7 myotome

Answer 3

1. Elbow and finger extension
2. Wrist flexion
3. Shoulder adduction

Question 4

C8 myotome

Answer 4

1. Elbow extension

2. Finger flexion

Question 5

T1 myotome

Answer 5

1. Finger abductors/adductors

Question 6

Muscle strength test

Answer 6

0=complete paralysis
1= trace contraction visible/palpable
2= FAROM w/o gravity
3= FAROM against gravity
4= FAROM against gravity and w/ little resistance
5= FAROM against gravity w/ max resistance (normal)

Question 7

Reflexes

Answer 7

1. C5: biceps
2. C6: brachioradialis
3. C7: Triceps

Grading
0= no response
1+ = slight but present response (sometimes normal)
2+ = brisk response (normal)
3+ = very brisk response (sometimes normal)
4+ = repeating response (clonus) (always abnormal)

Question 8

Dermatome sensory testing

Answer 8

C5: shoulder
C6: thenar eminence
C7: not reliable to test (3rd finger)
C8: hypothenar eminence
T1: medial forearm at cubital region
T2: Axilla 

Ways to test

1. Vibration
2. Proprioception
3. 2-pt. Discrimination

Question 9

Peripheral nerves

Answer 9

1. Axillary: lateral aspect of deltoid
2. Musculocutaneous: lateral forearm
3. Radial: dorsum webbing between thumb and index finger
4. Ulnar: medial tip of pinky
5. Median: tip of index finger

Question 10

Electrodiagnostic testing

Answer 10

Study of interaction between muscle fibers and nerves
1. Indications: 
  A. Numbness/tingling
  B. Pain
  C. Weakness
  D. Ambulation issues
  E. Muscle atrophy
  F. Fasciculation
  G. Trauma
2. Determines:
  A. Diagnosis: nerves/muscles
  B. Localization: lesion
  C. Prognostication: how
3. What you can dx:
  A. Peripheral nerve entrapment (carpal tunnel)
  B. Brachial plexopathy (Erb’s palsy)
  C. Motor neuron disease (ALS)
  D. Radiculopathy (C5 from pinched nerve)
  E. Neuromuscular disease (myasthenia gravis)
  F. Neuropathy (diabetic)
  G. Demyelination disease (Guillan-Barre)
  H. Myopathy (muscular dystrophy)

Question 11

Nerve conduction study

Answer 11

Part 1 of electrodiagnostic testing: test fxn of nerve, muscle, and neuromuscular junction

1. Send electrical signal from muscle and nerve to receiver thru area of suspected entrapment
2. Look at velocity, amplitude, and delay of signal

Question 12

EMG (radio needle)

Answer 12

Part 2 of electrodiagnostic testing: used to localize specific muscles
1. Needle connected to radio
A. Hear noise when muscles activated
B. Trained to know what to listen for