2. Examining the sensory system provides
information regarding the integrity of the
Spinothalamic Tract, posterior columns
of the spinal cord and parietal lobes of
the brain.
3. Equipment
Cotton ball
Objects to feel, quarter or key etc.
Test tubes with hot/cold H2O
Tuning fork, low pitched
4. Screening Test
Only necessary to evaluate the following
Lateral aspect of upper thighs
Inner aspect of upper arms
Dorsal or palmer surface of hands
Bottom or dorsal surface of feet
5. Neural Pathways
Sensory impulses travel to the brain via
2 ascending neural pathways
1. Spinothalamic tract
2. Posterior columns
Impulses originate in the afferent fibers of
the peripheral nerves, are carried
through the posterior dorsal root into
the spinal cord.
8. Assessment
Scatter stimuli over the distal and
proximal parts of all extremities and
trunk to cover most of the dermatomes.
Abnormal symptoms may indicate need
to test the entire body surface
Pain
Numbness
Tingling
9. Compare sensations on symmetric parts
of the body
If decrease in sensation
Systematic testing
From point of decreased sensation toward
sensitive area
Note where sensation changes
Map borders of deficient area, Diagram
10. Note if the pattern of sensory loss is
“distal”
Glove & stocking ( hands & feet)
Dermatones
C3- front of neck
T4 - nipples
T10 – umbilicus
C6 – thumb
L1 inguinal
11. Dermatomes
L4 – Knee
L5 – Anterior ankle & foot
Dermatome = band of skin innervated by
the sensory root of a single spinal nerve.
12. Light Touch Sensation
Use wisp of cotton
Ask clients to close both eyes and tell you
what they feel and where
Normal Findings
Correctly identifies light touch
In some older clients light touch and pain
sensations may be decreased
14. Pain Sensation
Pin prick
Tongue blade, dull & sharp
Ask to distinguish
2 sec. b/t each stimulus to avoid
summation
(frequent consecutive stimuli percieved as
one strong stimulus)
15. Abnormalities to pain
Analgesia = absence of pain sensation
Hypalgesia = decreased
Hyperalgesia = increased
Apply lightest pressure to obtain response
16. Temperature
Only tested when pain sensation is
abnormal.
Temp. & pain travel in the lateral
spinothalamic tract
Test tubes, hot & cold H2O
17. Vibration
Low pitched tuning fork (128Hz)
Distal interphalangeal joint (finger & big
toe)
Ask what the patient feels. Ask to tell when
the vibration stops and then touch the
fork to stop it. If impaired- proceed to
more proximal joints or bony
prominances.
18. Position ( Kinesthesia)
Passive movement of extremity
Finger or big toe up and down
Hold by sides b/t thumb and index finger
If position sense is impaired, move
proximally to next joint
If position sense intact distally , then it
is OK proximally.
19. Tactile Discrimination
Sensory cortex
Eyes closed during testing
Stereognosis= identification of an object
by feel
Astereognosis, inability to recognize objects
20. Number identification= GraphesthesiaNumber identification= Graphesthesia
Used when stereognosis prevented due to
motor impairment for ex. In arthritis
Use blunt end of pen/pencil to draw number
Two-point discrimination
Alternate double with single stimulus
Minimal distance1 from 2 points= less than
5mm on finger pads
21. Point Localization
Touch pt’s skin
Open eyes and point to where touched
Useful trunk & legs
Extinction
Simultaneously stimulate same area both
sides of body
Ask how many points felt and where
22. charting
If normal
Identifies light touch, dull and sharp
sensations to trunk and extremities.
Vibratory sensation, stereognosis,
graphesthesia, two-point discrimination
intact.
23. Abnormal results in these tests indicate
lesions of the sensory cortex.
These tests not done on children 6 yrs
and younger.
65yrs &older
loss of sensation of vibration at the ankle
Position sense in big toe may be lost
Tactile sensation impaired
24. Infants and toddlers
Little sensory testing
Hypoesthesia
Responds to pain by crying
General reflex withdrawal of all limbs
7 – 9mos.can localize stimulus