Sensory Assessment

Question 2

What is the purpose of a sensory assessment?

Answer 2

To assess somatosensory function and identify potential neurological deficits.

Question 3

What are the three types of sensation?

Answer 3

Superficial
deep
combined

Question 4

What does the anterolateral (spinothalamic) tract detect?

Answer 4

Pain
temperature
crude touch

Question 5

What does the DCML pathway detect?

Answer 5

Light touch (precise localization)
Two point discrimination
Pressure
Vibration
Proprioception (joint position sense and kinesthetic awareness)
Barognosis
Graphesthesia
Texture recognition
Stereognosis

Question 6

What is superficial sensation?

Answer 6

Pain (sharp/dull)
Touch awareness
Temperature
Pressure

Question 7

What is deep sensation?

Answer 7

Kinesthetic awareness/ joint movement sense
Proprioception/ joint position sense
Vibration

Question 8

What is combined cortical sensation?

Answer 8

Stereognosis
Tactile localization
Two point discrimination
Double simultaneous stimulation
Graphesthesia
Barognosis (recognition of weight)

Question 9

Why is vision eliminated during sensory tests?

Answer 9

To prevent visual compensation and ensure true sensory response.

Question 10

What should you do before testing a sensory modality?

Answer 10

Visually demonstrate so the patient knows what to expect

Question 11

Why test bilaterally in sensory assessments?

Answer 11

To compare affected vs. unaffected sides for more accurate localization.

Question 12

What must be checked before sensory testing begins?

Answer 12

Arousal and orientation

Question 13

Why do we start sensory testing with light touch and sharp/dull?

Answer 13

They provide quick insights into multiple pathways.

Question 14

What is the pattern of testing for dermatomes?

Answer 14

Top to bottom or in a consistent systematic order.

Question 15

What can peripheral distribution patterns suggest?

Answer 15

Localized nerve damage or polyneuropathy.

Question 16

What is the difference between absent, impaired and anesthesia?

Answer 16

absent: sensation completely lost, no sensibility in the affected region
impaired: decreased intensity compared to what is typically felt
anesthesia: all sensory modalities are lost

Question 17

How do you test tactile localization?

Answer 17

Ask the patient to say “yes” when touched and point to or describe the area.

Question 18

What tool is commonly used for light touch?

Answer 18

Cotton ball or tissue

Question 19

How do you vary light touch testing?

Answer 19

Randomize timing and occasionally ask during no stimulus.

Question 20

What does accurate tactile localization suggest?

Answer 20

Intact DCML pathway from periphery to cortex.

Question 21

What does sharp/dull testing assess?

Answer 21

Integrity of pain pathway via the lateral spinothalamic tract.

Question 22

What tools can be used for sharp/dull testing?

Answer 22

Safety pin (sanded) or paperclip

Question 23

How should sharp/dull stimuli be applied?

Answer 23

With enough pressure to indent but not blanch the skin; hold for a few seconds.

Question 24

What does loss of sharp/dull discrimination indicate?

Answer 24

Lesions in the anterolateral pathway.

Question 25

What is temperature testing used for?

Answer 25

To map areas of sensory loss in dermatomal or peripheral patterns.

Question 26

What temperatures are used in thermal testing?

Answer 26

Warm (40°C) and cool (10°C).

Question 27

How long should thermal stimulus contact be maintained?

Answer 27

Approximately 3 seconds.

Question 28

What does tactile threshold/pressure testing measure?

Answer 28

Minimal detectable pressure (light touch threshold).

Question 29

What tool is used for tactile threshold testing?

Answer 29

Semmes-Weinstein monofilaments (SWM).

Question 30

How are monofilaments used?

Answer 30

Apply perpendicularly with enough force to bend slightly; hold for 1-2 seconds.

Question 31

What does a higher monofilament number mean?

Answer 31

More force required to bend = more significant sensory loss.

Question 32

What population benefits most from tactile threshold testing?

Answer 32

Patients with diabetic neuropathy or nerve injuries.

Question 33

What does conscious proprioception involve?

Answer 33

Joint movement and position sense.

Question 34

How is joint movement tested?

Answer 34

Move joint randomly and ask if it is moving up or down.

Question 35

How is joint position tested?

Answer 35

move the patients joint and have them match the final position with the opposite limb or to report the position of the joint

Question 36

What does vibration testing evaluate?

Answer 36

Large beta peripheral nerve fibers and DCML neurons

Question 37

What tool is used for vibration testing?

Answer 37

128 Hz tuning fork.

Question 38

Where is vibration typically tested?

Answer 38

DIP joints of fingers/toes or medial malleolus

Question 39

What are combined cortical sensation tests dependent on?

Answer 39

Intact primary touch sensation.

Question 40

What is two-point discrimination testing?

Answer 40

Determining whether one or two points are felt with gradually reduced distance.

Question 41

How is 2-point discrimination tested?

Answer 41

Use calipers/paperclip; gradually decrease spacing until patient perceives one point.

Question 42

What does successful 2-point discrimination indicate?

Answer 42

Intact discriminative touch and DCML function.

Question 43

What is bilateral simultaneous touch testing?

Answer 43

Testing for sensory extinction by touching one side or both

Question 44

What does sensory extinction suggest?

Answer 44

Contralateral parietal lobe lesion.

Question 45

What is graphesthesia?

Answer 45

Ability to recognize letters or numbers drawn on the skin. Draw a number or letter on patients hand and ask them to identify It.

Question 46

What is stereognosis?

Answer 46

Ability to recognize an object by touch alone. Place an object in the patient’s hand; ask them to identify it.

Question 47

What does impaired stereognosis indicate?

Answer 47

Lesion in the contralateral parietal cortex or white matter.

Question 48

What is barognosis?

Answer 48

Ability to distinguish the weight of objects.

Question 49

What is tactile extinction?

Answer 49

Inability to perceive both stimuli during simultaneous bilateral touch.

Question 50

What is a dermatome?

Answer 50

An area of skin innervated by a single dorsal root.

Question 51

What is the typical grading scale for sensory testing?

Answer 51

0 = absent 1 = impaired 2= normal NT= not testable

Question 52

What are examples of peripheral distribution sensory loss?

Answer 52

Carpal tunnel radial nerve palsy

Question 53

What are examples of dermatomal sensory loss?

Answer 53

Cervical or lumbar radiculopathy.

Question 54

What is polyneuropathy?

Answer 54

Symmetrical peripheral nerve damage often in diabetes or chemotherapy.

Question 55

Why test from distal to proximal?

Answer 55

Sensory loss in polyneuropathy typically starts distally

Question 56

Why is light touch testing often prioritized?

Answer 56

It helps localize lesions and assess DCML function.

Question 57

What is the significance of intact light touch but impaired graphesthesia?

Answer 57

Potential parietal lobe dysfunction.

Question 58

Why is it important to document asymmetry?

Answer 58

It helps localize central vs. peripheral lesions.

Question 59

What does a lesion in the primary sensory cortex affect?

Answer 59

Localization of sensation though touch may still be detected.