Sensory Exam (H&P)

What are the sensory pathways of the CNS

Spinothalamic Tract

Posterior Columns

Spinocerebellar Tract

What sensations travel on the anterior spinothalamic tract

Touch (Crude and Deep Pressure)

What sensations travel on the lateral spinothalamic tract

Pain

Temperature

Pathway of Spinothalamic Tract

Skin Receptors

Posterior Root Ganglion

Grey Matter of Spinal Cord

Cross to Opposite Side (1-2 segements up)

Medulla Oblongata + Midbrain

Thalamus

Post Central Gyrus

What separates the posterior columns

Fasciculus cuneatus (T6 and above)

fasciculus gracilis (T7 and below)

What sensory information is relayed by posterior columns

Position sense

Fine touch

Vibration

Joint position

Point localization

2 point discrimination

Posterior Column Pathway

Skin Receptors

Posterior Root Ganglion

White Column

Medulla (Crosses)

Thalamus

Post Central Gyrus

What information is relayed by spinocerebellar

Unconscious proprioception

Pathway of Spinocerebellar Tract

Dorsal Horn of Spine

Lateral White Column

Cerebellum

Difference between anterior and posterior spinocerebellar tracts

Anterior spinocerebellar – crosses over when enters spinal column, then crosses over again in cerebellum to finish in ipsilateral cerebellum

Posterior spinocerebellar – Goes straight up on ipsilateral side to cerebellum

T4 Dermatome

Level of the nipples

T10 Dermatome

Umbilicus

L1 Dermatome

Inguinal Canal

L5 Dermatome

anterior ankle and foot

Great toe

S1 Dermatome

Lateral Foot

Fifth Toe

S5 Dermatome

Anus

What parts of the sensory exam look at the posterior column

Light Touch

Vibration Sense

Joint Position Sense

What parts of the sensory exam look at the spinothalamuc

Crude Touch

Pin Prick

Temperature

What parts of the sensory exam look at the cortical paths

Stereognosis

Graphesthesia

Extiniction

C3 Dermatome

Front of Neck

C4 Dermatome

Shoulder

C6 Dermatome

Thumb

C8 Dermatome

Ring and Little Finger

L3 Dermatome

Medial Thigh

L4 Dermatome

Medial Calf

What dermatomes are assessed during sensory exam

C3

C4

C6

C8

T4

T10

L1

L3

L4

L5

S1

Difference between Fine Touch and Crude Touch

Fine touch – lightly touch patient with a small piece of gauze or cotton wisp and evaluates posterior column

Crude touch- touch patient with fingers and evaluates spinothalamic tracts

What is used for vibration sense

128 Hz tuning fork

Where is vibration sense tested

Thumb

elbow

clavicle

Big toe

lateral malleolus,

patella

How do we assess proprioception

Move the distal phalanx (index finger and big toe)

Have patient tell you if toe is up or down.

Stereognosis

Patient identifies object placed in the hands with eyes closed

What does stereognosis assess

Nondominant Parietal Lobe

Astereognosis

Abnormal sterognosis

Graphesthesia

Ability to identify a number written in the palm of one’s hand with eyes closed (numbers 0-9)

What does graphestheisa assess

Dorsal column (light touch)and nondominant parietal lobe

Extinction

touch patient in two locations at the same time and ask the patient where touched

What does extinction assess for

Parietal lobe lesions  feel the individual touches but may “extinguish” the sensation of the side contralateral to the lesion

Two point discrimination

Continue to decrease distance between the two ends of the paperclip until patient can no longer discriminate between one and two points

<5mm on finger pad

What does two point discrimination test

both posterior column and cortical functioning

Causes of Parietal Lobe Dysfunction

CVA

Hemorrhage

Tumor

Demyelination (MS)

How does parietal dysfunction present

• Nondominant parietal lobe:

  • Stereognosis and graphesthesia

• Contralateral parietal lobe:

  • Extinction

How does thalamic dysfunction present

Hemisensory loss of all modalities on contralateral side

Causes of Thalamic Dysfunction

CVA

Hemorrhage

Tumor

Demyelination (MS)

How will brainstem dysfunction present

Loss of sensation on the ipsilateral face and contralateral side of the body

Cause of Brainstem dysfunction

CVA

Hemorrhage

Tumor

Demyelination (MS)

How will complete transverse lesion of the spinal cord present

Hyperesthesia (increased touch/pinprick sensation) at the upper level

Loss of all modalities below the lesion

Causes of Complete Transverse Lesion

Trauma

Spinal cord tumor causing compression

Transverse myelitis

MS

Intraspinal tumors

Spinal abscess

How will hemi section of cord present

Loss of joint position sense and vibration sense on same side as lesion

Loss of pain and temperature on opposite side of lesion

Loss of motor function on same side as the lesion

Brown Sequard Syndrome

A condition of sensory loss due to a hemisection of the spinal cord

Causes of Hemisected Spinal Cord

Trauma

Spinal cord tumor causing compression

Transverse myelitis

MS

Intraspinal tumors

Spinal abscess

How will central cord dysfunction present

Loss of pain and temperature at the level of the lesion (where spinothalamic fibers cross the cord)

Loss of motor function at the level of the lesion (UE > LE)

Some decreased motor function at levels below injury

Cause of Central Cord Dysfunction

Trauma causing cervical neck hyperextension (esp. in elderly with coexistent spinal stenosis)

Syringomyelia (fluid filled cavity in the spinal cord)

How will anterior spinal lesion present

Loss of pain and temperature bilaterally below the level

Joint position sense and vibration remain

Loss of motor function bilaterally below the level

Cause of Anterior Spinal Lesion

Anterior spinal artery emboli or thrombosis (rare)

Trauma

How does posterior column lesion present

Loss of joint position sense and vibration sense bilaterally

Pain and temperature remain intact

Causes of Posterior Column Lesion

• Trauma

• Tumor

• Multiple sclerosis

• Subacute degeneration of the cord

  • Vitamin B12 deficiency

  • Tabes dorsalis

Common Nerves for Singular Nerve Dysfunction

Median

Ulnar

Peroneal

Lateral Cutaneous Nerve

Common Cause of Singular Nerve Dysfunction

Entrapement

Saturday Night Palsy

Compression of radial nerve

Cause of Radial nerve paralysis

Fracutre

Entrapement

How does radial nerve paralysis present

Wrist Drop (weak extensors)

How does Long thoracic nerve paralysis present

weakness of serratus anterior

Winged scapula

Patient complains of shoulder weakness

Cause of Long thoracic nerve paralysis

trauma t

repetitive activities

Erb Duchenne paralysis (Erb’s Palsy

Lower motor neuron paralysis of brachial plexus, mostly C5-C6

Cause of Erb’s Palsy

Birth Injury

Blow to Shoulder

Presentation of Erb’s Palsy

Arm hangs limb

Finger Flex

Turned Posterior

Loss of sensation

Klumpke paralysis (“claw hand”)

Lower motor neuron injury of C8 and T1

Cause of Klumpke paralysis

birth injury

trauma where person grabs something while falling

Presentation of Klumpke Paralysis

Forearm flat

Wrist and Fingers Tighten

Motor Loss of FCU and ulnar half of FDP

Lose of ulnar and forearm sensation

Causes of Polyneuropathy

Diabetes mellitus

ETOH

Medications (ex: chemotherapy)

Heavy metals

HIV

Guillain-Barre

Hereditary

Idiopathic