OT 501 chp 23

Sensation (Sensibility)

Body function that influences motor and processing aspects of performance skills.

Proprioception

Awareness of body or joint position in space.

Stereognosis

The ability to identify an object by touch while vision is occluded.

Neuroplasticity

The brain's ability to change, remodel, and reorganize to adapt to new situations.

Cutaneous sensation

Sensation involving pain, temperature, and touch.

Proprioceptive sensation

Sensory information arising from joints, skeletal muscles, and tendons.

Mechanoreceptors

Sensory receptors that respond to touch, pressure, stretch, and vibration.

Thermoreceptors

Sensory receptors that respond to heating and cooling.

Nociceptors

Sensory receptors that detect painful stimuli.

Paresthesia

A tingling, electrical, or prickling sensation.

Tinel's sign

Paresthesia produced by tapping over an affected nerve.

Hyperalgesia

Increased pain, which may occur during nerve regeneration.

Hypersensitivity

Increased sensory pain.

Dysesthesia

An unpleasant sensation that may occur spontaneously or in response to stimulation.

Allodynia

Pain caused by a stimulus that normally would not cause pain.

Dermatome

An area of skin supplied by one spinal dorsal root and its spinal nerve.

Neuropathy

Impairment of the peripheral nervous system.

Large sensory nerve fiber modalities

Vibration, light touch, and proprioception.

Small sensory nerve fiber modalities

Temperature and pain.

Prerequisites before OT sensory testing

Obtain client history, review medical information, and consider motor and functional findings.

Hand support rationale during sensory testing

Prevents movement from providing extra sensory cues and interfering with accuracy.

Visual condition during sensory testing

Occluded (blocked from viewing).

Sharp/dull testing target

Pain and protective sensation.

Sharp/dull testing score: Intact protective sensation

Correct identification of sharp and dull on 5/5 trials.

Sharp/dull testing score: Diminished protective sensation

Correct identification on 1/5 to 4/5 trials.

Sharp/dull testing score: Absent protective sensation

Correct identification on 0/5 trials or inability to perceive touch.

Protective function of temperature awareness

Protects the client from burns and thermal injuries.

Rationale for pre-modality temperature testing

Impaired temperature awareness increases risk of burn or injury from heat/cold modalities.

Compensatory strategy for impaired temperature awareness

Test temperature using an unaffected body part prior to exposure.

Assessment target of two-point discrimination

Receptor density and discriminative sensation.

Testing site for static two-point discrimination

The volar tip of each finger.

Initial static two-point discrimination distance

6 mm.

Static two-point discrimination: Normal range

1–5 mm.

Static two-point discrimination: Fair range

6–10 mm.

Static two-point discrimination: Poor range

11–15 mm.

Static two-point discrimination: Single point perceived

Indicates protective sensation only.

Static two-point discrimination: Zero points perceived

Indicates an anesthetic area.

Value of moving vs. static two-point discrimination in nerve recovery

Moving discrimination returns before static discrimination, indicating early sensory recovery.

Moving two-point discrimination: Normal range (ages 4–60)

2–4 mm.

Moving two-point discrimination: Normal range (ages 60+)

4–6 mm.

Target of static touch-pressure testing

Minimum pressure required for the client to perceive touch.

Instrument used for touch-pressure testing

Semmes-Weinstein monofilaments.

Starting monofilament size in touch-pressure testing

2.83.

Semmes-Weinstein monofilament: Green category

Normal light touch.

Semmes-Weinstein monofilament: Blue category

Diminished light touch.

Semmes-Weinstein monofilament: Purple category

Diminished protective sensation.

Semmes-Weinstein monofilament: Red category

Loss of protective sensation.

Monofilament response: Untestable at 6.65+

Inability to feel the largest monofilament.

Sequence rationale: Touch pressure before two-point discrimination

Light touch must be intact for the client to perceive the two-point stimulus.

Client verbal response for perceived monofilament

"Touch."

Assessment target of the Ten Test

Moving light-touch sensation evaluated by comparing affected area to normal area.

Ten Test: Normal score

10/10.

Procedure for testing proprioception

Move a joint with vision occluded and ask client to identify direction of movement.

Proprioception testing score: Intact

Correct responses on 3/3 trials.

Proprioception testing score: Diminished

Correct responses on 1/3 to 2/3 trials.

Proprioception testing score: Absent

0/3 correct responses.

Kinesthesia

Awareness of joint movement.

Dexterity

Skill and ease in using the hands.

Dellon-Modified Moberg Pickup Test (DMMPUT)

Standardized assessment of hand dexterity and functional sensory ability.

DMMPUT: Standardized object count

12 objects.

DMMPUT Test 1

Speed test assessing how quickly objects are placed into a box with vision.

DMMPUT Test 2

Tactile identification test where vision is occluded and objects are identified.

Two sensory inputs required for stereognosis

Touch and proprioception.

Importance of stereognosis in daily occupations

Allows object identification and manipulation without visual cues.

Impact of sensory loss on occupational performance

Compromises motor and processing performance necessary for daily tasks.

Danger of lost protective sensation

Risk of sustaining unnoticed injuries or burns.

Primary compensatory sense for impaired hand sensation

Vision.

Sensory distribution affected by carpal tunnel syndrome

Volar thumb, index finger, middle finger, and radial half of ring finger.

Sensory deficits typical of CNS brain involvement

Deficits in proprioception, stereognosis, and sensory processing.

Sensory deficits typical of PNS injury

Deficits in touch-pressure, pain, temperature, discrimination, or proprioception.

Importance of neuroplasticity in sensory rehabilitation

Enables neural reorganization through functional activity and sensory experience.

Core neuroplasticity principle in sensory rehab

"Use it or lose it" — disuse negatively alters neural pathways, whereas active use promotes recovery.

Overall purpose of OT sensory evaluation

Determine how sensory dysfunction impacts safety, performance, and function.

Role of sensory testing in OT intervention design

Guides selection of sensory retraining, compensatory strategies, and safety measures.

Purpose of compensatory sensory strategies

Protect the client from injury and assist in task performance when sensory recovery is limited.