Patterns of Sensory Loss - Somatosensory disorders - Lily Flashcards
-35 year old rugby player presented with pain in neck after a rugby match.
-Rapidly developed vertigo, unsteadiness, hoarse voice and difficulty swallowing.
-On examination, there was a left horners syndrome, and loss of pain and temperature in the left side of the face, but the right side of the body.
WHERE IS THE LESION?
- loss of pain temperature from left side of face but right side of body = LEFT SIDE SPINAL TRACT / LATERAL SPINOTHALAMIC TRACT LESION AT THE LEVEL OF THE (CLOSED) MEDULLA as well as left sympathetic trunk lesion.
- Horner’s syndrome arises when the sympathetic trunk is damaged. symptoms occur on the same side as the lesion. It is characterized by miosis (constricted pupil), ptosis (droopy eyelid), anhidrosis (decreased sweating), with or without enophthalmos (inset eyeball).
disordered temperature sensation in left leg and loss of vibration and proprioception on the right.
Where is the lesion?
- loss of temperature in left leg = spinothalamic lesion.
- Loss of vibration and proprioception on the right = dorsal column.
Lesion is right side below T6.
- Loss of strength in both legs (paraplegia).
- loss of pain and temp below umbilicus.
- vibration and proprioception preserved.
Where is the lesion?
Because dorsal column unaffected then lesion is anterior to the gracile / cuneate fascicles and covers lateral corticospinal tract and spinothalamic tract.
Spinal cord has anterior spinal artery and posterior spinal artery. There is lack of blood supply from the anterior spinal artery!!!
- loss of strength = lateral corticospinal tract lesion on both sides.
- loss of pain and temp below umbilicus = spinothalamic tract lesion on both sides below T10.
Sudden onset loss of sensation of the left side of the whole body, including the face.
Accompanied later by deep aching pain in left sided limbs.
Where is the lesion?
Lesion of Ventral posterior nucleus of thalamus on Right side.
(has to above the decussation of the dorsal column tract. so that the lesion will affect the same side of the body for both spinothalamic and dorsal column sensation)
- Gradually developed loss of pain and temperature sensation in both hands and across her body in a cape like distribution.
- also complained of wasting in small muscles of hands
- weakness in the legs.
SYRINGO MYELIA
- a cyst in the cervical region compresses the tracts.
- loss of pain temperatue sensation in hands = spinothalamic , dermatomes C6,7,8
- loss of pain temperature sensation across body = spinothalamic sensation lost in dermatomes C6 - T4?
- wasting in small muscles of the hands = LMN lesion of brachial plexus
-Lesion of anterior part of the spinal cord from C6 - C8 that includes both spinothalamic tracts and ventral rootlets. Also compresses lateral corticospinal tract (weakness in legs).
But doesn’t affect the dorsal column pathway.
- numbness to pain, fine touch and vibration with a “glove and stocking” distribution. (forearm and lower leg)
- Reflexes absent.
Nerve conduction studies showed axonal sensorimotor polyneuropathy.
(polyneuropathy is the general degeneration of peripheral nerves that spreads towards the centre of the body.)
What are the causes of peripheral neuropathy?
1) Diabetes Mellitus
2) Autoimmune (guillain-barre, vasculitis)
3) Toxic
4) Vitamin Deficiency
5) Paraneoplastic
6) Chronic Kidney , liver disease
7) Inherited (charcot-marie-tooth disease)
- 70 yr old lady with vitiligo.
- gradual onset numb feet.
- feels unsteady tends to fall on uneven ground or in the dark.
- found to be anaemic with high mean cell volume.
- loss of vibration sense up to waist.
- loss of proprioception in feet.
- could still feel pin prick
- normal strength.
- walked with sensory ataxia.
- loss of vibration sense up to waist = dorsal column
- loss of proprioception in feet = dorsal column
- sensory ataxia is not a problem with the cerebellum but a problem with the sensory input.
what is syringo myelia?
a progressive disease in which a longitudinal cyst forms in the cervical region of the spinal cord. It contains CSF , as it enlargens it compresses the tracts surrounding it.
Results in wasting of the hand muscles and loss of sensation.
The cyst can move along the spinal tract causing symptoms in those areas also.
What is the classical distribution of peripheral neuropathy?
“glove and stocking”
forearm and lower leg
What is the cause of a pure sensory stroke?
Thalamic Infarct
What would the symptoms be in an infarct of the Ventral posterior nucleus of the thalamus?
Loss of sensation on the contralateral side of the lesion
loss of both dorsal column spinothalamic
