Light touch sensory testing - Peripheral Nerve Injuries (median, axillary, femoral)

Question 1

What is the purpose of the technique i.e. what are you measuring and why?

Answer 1

Ability to perceive sensation of light touch
Identify nerve injuries

Question 2

How do you know whether the measurement is normal

Answer 2

Normal = normal and equal sensation in all areas of limb

Abnormal = certain dermatomes affected - absent, diminished or heightened sensation

Damage to spinal root nerve = abnormal sensation in particular dermatomes

Question 3

What principles are used in carrying out (application) the technique?

Answer 3

1) Patient comfortable, explain procedure, informed consent
2) Give patient example of what is normal - use tufted cotton wool in an unaffected area
3) ask patient to close eyes
4) compare right to left distal to proximal in circumferential pattern
5) “could you say yes when you feel the cotton wool?”
6) record sensation as either normal impaired or absent
7) document

Question 4

What structures/processes are being assessed?

Answer 4

Assessment focused on either dermatomes or peripheral nerves

Question 5

Precautions / contraindications

Answer 5

Skin conditions
Open wounds

Question 6

How would you document this?

Answer 6

Date, Time, Patient name
Explanation of procedure & gaining informed consent
Nerve being tested
Normal response to control light touch?
Working proximal to distal, circumferentially.
Same sensation in both limbs?
Any impairment - what type and where, dermatomes corresponding to what nerve.
Adverse affects?
Sign

Question 7

How would you assess sensation in the median nerve

Answer 7

Conduct test in forearm

Question 8

How would you assess sensation in the axillary nerve?

Answer 8

Conduct test in shoulder/ upper arm

Question 9

How would you assess sensation in the femoral nerve?

Answer 9

Conduct test on leg