N26 Somatosensory System Lesions

Question 1

Anesthesia

Answer 1

Complete loss of TOUCH sensation

Question 2

Hypesthesia

Answer 2

partial loss of TOUCH sensation

Question 3

Hyperesthesia

Answer 3

abnormal increase in sensitivity of the skin when touched

Question 4

Paresthesia

Answer 4

spontaneous sensations (burning, tingling, pins and needles)

Question 5

Dyesthesia

Answer 5

impaired TOUCH sensation short of anesthesia (peripheral nerve injury) abnormal sensations with no stimuli, stimuli with decreased sensations

Question 6

Allodynia

Answer 6

when ordinarily non-painful stimuli evoke pain

Question 7

Analgesia

Answer 7

complete loss of pain appreciation

Question 8

Hypalgesia

Answer 8

partial loss of pain appreciation

Question 9

Hyperalgesia

Answer 9

abnormal increased sensitivity to painful stimuli

Question 10

Radicular pain

Answer 10

shooting pain in dermatomes (sciatica)

Question 11

Causalgia (CRPS)

Answer 11

severe, persistent, burning pain related to trauma, even outside of nerve area

Question 12

Is the pain in a specific dermatome, then

Answer 12

spinal nerve root problem

Question 13

Sensory loss restricted to one area of the body

Answer 13

Mononeuropathy

Question 14

Sensory loss symmetric on both sides

Answer 14

polyneuropathy

Question 15

Sensory loss of one whole limb or side of body

Answer 15

central or peripheral problem

Question 16

Sensory loss of one or more modality

Answer 16

is pattern of loss same for all modalities

Question 17

Spinal cord lesions are unique in that they

Answer 17

create dissociated sensory loss or specific loss of pain and temperature OR fine touch and proprioception

Question 18

Brown-Sequard hemicord/hemisection

Answer 18

loss of fine touch, proprioception, 2-pt discrimination on ipsilateral side of lesion, BUT loss of pain and temperature on contralateral side 1-2 segments below

Question 19

Lesion to caudal brainstem (caudal pons and all of medulla)

Answer 19

loss of pain and temperature sensation on the contralateral side of the body and ipsilateral side of the face

Question 20

Thalamic and cortical lesions result in

Answer 20

CONTRALATERAL side of body and head

Question 21

Spinal Nerve lesion (receptor, peripheral process, or DRG)

Answer 21

IPSILATERAL loss of all sensation

Question 22

Lesion of DC-ML in spinal cord

Answer 22

lost or diminished sensations on IPSILATERAL dermatomes

Question 23

Lesion of DC-ML at level of dorsal nuclei

Answer 23

lost or diminished sensations of IPSILATERAL body

Question 24

Lesion of DC-ML at level of ML, thalamic VPL, internal capsule, cerebral cortex 3,1,2

Answer 24

lost or diminished sensations on CONTRALATERAL body

Question 25

Lesion to DC-ML results in loss of

Answer 25

decreased vibratory sense, 2-pt discrimination, tactile stimuli, conscious proprioception, impaired motor function

Question 26

Dorsal Column ataxia

Answer 26

impaired ability to coordinate voluntary muscle movements

Question 27

Neurosyphilis

Answer 27

may cause degeneration in DC-ML (lumbosacral levels)

Question 28

Romberg Sign

Answer 28

indicates damage to DC-ML because a (+) sign indicates diminished joint position (proprioception); assuming that vestibular function is intact

Question 29

Lesion to the posterior parietal lobe

Answer 29

loss of secondary modalities (stereognosis and graphesthesia), whilst primary modalities are intact (vibration, touch, proprioception)

Question 30

Lesion to the posterior parietal lobe (5,7)

Answer 30

Astereognosis: inability to recognize an object by touch; Agraphesthesia: inability to idenitfy a letter or number wrote on skin; Neglect syndrome: distorted image of self in space; extinction phenomenon

Question 31

extinction phenomenon (hemineglect)

Answer 31

inability to identify stimulus presented on opposite side of lesion

Question 32

Lesions in the STT in spinal cord

Answer 32

lost or diminished pain, temperature, and crude touch in all CONTRALATERAL segments below lesion

Question 33

Lesions in thalamic VPL, internal capsule, or 3,1,2

Answer 33

lost or diminished pain, temperature, and crude touch in all CONTRALATERAL to lesion

Question 34

Thalamic pain syndrome (CPSP or Dejerine-Roussy)

Answer 34

lesion to thalamic VPL initially results in loss of all sensation, but eventually pain returns in contralateral side (due to SRTT bringing slow, burning pain to thalamic intralaminar nuclei)

Question 35

Results of lesion to ALS

Answer 35

Analgesia (loss of pain sensation), thermoanesthesia (loss of temperature sensation), hypesthesia (may have diminished touch sensation)

Question 36

Lesions to trigeminal peripheral system

Answer 36

IPSILATERAL loss of pain, temp, discrimination, proprioception, vibration and IPSILATERAL paralysis of muscles of mastication

Question 37

Trigeminal Neuralgia (Tic Douloureux)

Answer 37

compression of trigeminal sensory nerve causing excruciating pain

Question 38

Trigeminal motor nucleus lesion

Answer 38

IPSILATERAL paralysis or muscles of mastication

Question 39

Trigeminal sensory nucleus lesion

Answer 39

lost or diminished sensations to IPSILATERAL side of lesion

Question 40

Lesion to spinal trigeminal lesion

Answer 40

loss of pain and temperature to IPSILATERAL head

Question 41

Lesion to chief sensory trigeminal lesion

Answer 41

loss of discriminative sensation on IPSILATERAL side

Question 42

Lesions to VTTT, thalamic VPM, internal capsule, 3,1,2

Answer 42

CONTRALATERAL loss of pain, temp, discrimination, proprioception, vibration (VTTT at spinal trigeminal = CONTRALATERAL pain and temp)

Question 43

Spinal (Neural) Shock

Answer 43

1-6 weeks post injury to spinal cord = absence of neural activity at any level = acute flaccid paralysis (hyporeflexia or areflexia, hypotension (loss of sympathetic innervation), flaccid paralysis)