Somatosensory System Lesions and Chronic Pain Syndromes

Question 1

What is the following a defintion of?

any pathology or injury affecting either the peripheral nervous system, the central nervous system, or both; deficits can occur at any point in the system

Answer 1

Sensory dysfunction

Question 2

Injury to DCML pathway inferior to decussation in the caudal medulla causes what?

Answer 2

Ipsilateral loss of light touch and conscious proprioception below the level of the lesion

Question 3

Injury to DCML pathway superior to decussation in the caudal medulla causes what?

Answer 3

Contralateral loss of light touch and conscious proprioception

Question 4

Where does decussation of the spinothalamic tract take place?

Answer 4

Within the spinal cord

Question 5

Injury to spinothalamic tract as it ascends through the spinal cord or brainstem will cause what?

Answer 5

Contralateral loss of pain sensation below the level of lesion

Question 6

What is the following a defintion of?

Movement incoordination that is not due to weakness

Answer 6

Ataxia

Question 7

What type of Ataxia is the following

Caused by lesions located in the peripheral and central structures that transmit and interpret somatosensory information along DCML pathway

Answer 7

Sensory Ataxia

Question 8

Lesions in thalamus, thalmaci radiations or somatosensory cortex would cause contralateral or ipsilateral sensory ataxia?

Answer 8

Contralateral Sensory Ataxia

Question 9

Lesions below decussation would cause contralateral or ipsilateral sensory ataxia?

Answer 9

Ipsilateral Sensory Ataxia

Question 10

The following is a pathology of what?

Impairment in movement due to central motor structures not able to get proprioceptive information about muscle length, velocity of limb movement impacting motor planning, coordination and execution of movement

Answer 10

Sensory Ataxia

Question 11

What is the following a definition of?

Stomping feet on the ground and looking at feet to compensate for sensory loss, wide-base, unsteady, high steppage gait

Answer 11

Sensory Ataxia Gait

Question 12

What is the following Clinical Presentation of?

• impaired awareness of the position and movements of limbs
• use vision to substitute for loss of proprioception so symptoms increase when can’t use vision in darker environments
• Positive Rhomberg test
• Impairments in two-point discrimination

Answer 12

Sensory Ataxia

Question 13

What are the following health condition lesions represent?

Peripheral nerve: large, myelinated fiber neuropathies
Dorsal root: tabes dorsalis
Dorsal Column: Spinal Cord Lesions
Medial Leminscus: brainstem lesions
Thalamus: thalamic syndrome
Parietal Lobe: primary somatosensory cortex & secondary somatosensory area lesions

Answer 13

Sensory Ataxia

Question 14

What is the following a defintion of?

Pain occurs in the absence of clearly identifiable tissue injury and is primarily due to central sensitization

Answer 14

Chronic Back Pain

Question 15

What are the most common chronic primary pain conditions (4)?

Answer 15

• Fibromyaglia
• Migrane
• Complex Regional Pain Syndrome
• Chronic Nonspecific Low Back Pain

Question 16

What is the following a defintion of?

Causes tenderness of muscles and adjacent soft tissues, stiffness of muscles, and widespread aching pain that does not folow dermatomal or peripheral nerve distributions

Answer 16

Fibromyaglia

Question 17

What is the following a defintion of?

Brain-initiated central sensitization syndrome characterized by dysfunction within the hypothalamus and the trigemino-thalamo-cortical pathway

Answer 17

Migrane

Question 18

What is the following a characteristics of?

• located unilaterally
• pulsating quality
• produce moderate to severe pain intensity
• aggravated or caused by avoidance of routine physical activity

Answer 18

Migrane

Question 19

What are the following triggers of?

• Stress
• Barometric pressure changes
• Lack of sleep
• Low blood sugar
• Menstruating women
• Decline in estrogen

Answer 19

Migranes

Question 20

What is the following a defintion of?

Result of an aberrant response to any degree of trauma

Answer 20

Complex regional pain syndrome

Question 21

What are following signs and symptoms of?

• Severe, spontaneous pain, hyperglasia, allodynia
• pain, vascular changes, and atrophy in a regional distribution in one upper or lower limb

Answer 21

Complex Regional Pain Syndrome

Question 22

What is the following a defintion of?

Back pain that cannot be attributed to a specific stuctures that does not resolve after 6-12 weeks since onset

Answer 22

Chronic nonspecific low back pain

Question 23

What is the following pathlogy of?

• central sensization; initiation site uncertain
• neural region affected: central nervous system

Answer 23

Chronic nonspecific low back pain

Question 24

What is the following a defintion of?

Caused by an underlying disease or specific injury and is mediated by both peripheral and central sensitization

Answer 24

Chronic secondary pain

Question 25

Increased activity of peripheral nociceptors entering the spinal cord due to peripheral sensitazation after a peripheral injury drives ____ changes that lead to ______ ______

Answer 25

Cellular; Central Sensitization

Question 26

# What is the following a defintion of? Pain that results from a direct consequence of a lesion or disease affecting the somatosensory system

Answer 26

Neuropathic pain

Question 27

What arises from abnormal neural activity anywhere along the nocicpetive pathways, including in peripheral nerves, the dorsal horn, the brainstem, and the cerebrum

Answer 27

Neuropathic pain

Question 28

# What is the following a defintion of? - Locations outside of the receptors that generates action potentials - Generates action potential without peripheral stimulatin causing spontaneous pain sensations - Myelin Damage

Answer 28

Ectopic foci

Question 29

# What is the following a defintion of? Excessive production of mechanosensitive, chemosensitive, and voltage-gated ion channels which are inserted into the area of demeylination enabling generation of action potentials in addtion to their normal role of conducting action potentials

Answer 29

Myelin Damage

Question 30

# What is the folloiwng a defintion of? - occurs in demyelination regions as a result of lack of insulation between neurons - action potential in one neuron may induce an action potential in another neuron

Answer 30

Ephatic Transmission

Question 31

# What is the following a defintion of? - most common cause of neuropathic pain - denervation of the nerves distal to the dorsal root ganglion results in lack of sensation from that nerve's receptive filed and often parethesias - partial damage to nerve can result in allodynia and sensation similar to electric shock - formation of neuroma - small fiber neuropathy

Answer 31

Peripheral generation

Question 32

# What is the following a defintion of? - twisted knot of nerve fibers and connective tissue

Answer 32

Formation of nueroma

Question 33

# What is the following a defintion of? - direct damage to neurons within central nervous system - pain felt in part of the body that corresponds to the lesioned brain or spinal cord area - occurs after deafferrentation or denervation

Answer 33

Central Generation

Question 34

# What is the following a defintion of? occurs when proximal axons of primary afferents are destroyed leaving spinal cord dorsal horn neurons without any peripheral input resulting in abnormal activity in the dorsal horns

Answer 34

Deafferentaion

Question 35

# What is the following a defintion of? Painful sensation post-amputation in the missing part of the limb secondary to peripheral and central mechanisms

Answer 35

Phantom Pain