deck_2770135 Flashcards
What is the spinal tract that is associated with fine touch and proprioception?
Dorsal Column Tract
What is the spinal tract that is associated with pain and temperature?
Lateral Spinothalamic Tract
What is the spinal tract that is associated with crude touch and pressure?
Anterior Spinothalamic Tract
What is the spinal tract that is associated with unconscious proprioception?
The Anterior and Posterior Spinocerebellar tractsand The Cuneocerebellar Tract
Describe the route of the dorsal column tract
Receptors to medullaGracile/ Cuneate nucleus in the medulla to the venteroposterolateral nucleusVPL nucleus to the primary somatosensory cortex
Describe the 1st order neurones in the dorsal column tract
Cell bodies are found in the dorsal root ganglionStay on the ipsilateral sideFibres from lower limb = fasciculi gracilisFibres from upper limb = fasciculi cuneate
Describe the 2nd order neurones in the dorsal column tract
Run from the gracile/cuneate nucleus to venteroposterolateral nucleus of the thalamus, via the pons and the midbrain through the medial lemniscus- cell bodies found in the nucleus gracilis/cuneate
Where does the dorsal column tract dessucate?
In the medulla
Describe the third order neurones in the dorsal column tract
Run from the venteroposterolateral nucleus of the thalamus to the primary somatosensory cortes via thalamocortical radiations- terminate in the medial aspect of the somatosensory cortex
What happens if there is damage to the dorsal column tract?
Below the medulla, there will be damage to the ipsilateral side
What are the clinical signs that would occur with damage to the dorsal column tract?
Loss of tactile senseLoss of proprioceptionInability to identify objects placed in the hand
Describe the route of the lateral spinothalamic tract
Nociceptors to dorsal hornDorsal horn to venteroposterolateral nucleus of the thalamusThalamocortical radiations ascend to the primary somatosensory cortex
Where does dessucation occur in the lateral spinothalamic tract?
At the level of entry into the spinal cord
Where do you find the cell bodies of the 1st order neurones of the lateral spinothalamic tract?
In the dorsal root ganglia
Describe what happens when you get damage to the lateral spinothalamic pathway
Loss of pain and temperature sensation on the contralateral side. - can have some sensation remaining 1 or 2 levels below, as some 1st order neurones ascend/descend 1 or 2 levels in the zone of Lissauer before synapsing with their second order neurones.
Which nerves are affected when there is a tumour or a lesion that expands from the grey matter?
The sacral and lumbar fibres lie dorsalaterally to the thoracic and cervical fibres, so the T and C will be affected first. Initially, this causes sacral and lumbar sparing as they will not be affected initially.
Describe the path of the anterior spinothalamic tract
Same as the lateral spinothalamic tractNociceptors to dorsal hornDorsal horn to venteroposterolateral nucleus of the thalamusThalamocortical radiations ascend to the primary somatosensory cortex
Describe the path of the posterior spinocerebellar tract
Neurones run from the receptors to lamina VII of the spinal cord, then the fibres ascend up to the cerebellum on the ipsilateral side
Describe the path of the anterior spinocerebellar tract
Neurones run from the receptors to lamina VII of the spinal cord, then dessucate in the spinal cord and ascend in the anterolateral white matter, recross to the ipsilateral side at the superior peduncle of the pons, then runs to the cerebellum.
What type of information does the anterior and posterior spinocerebellar tracts carry?
Information about whole limb movements and postural adjustments to the cerebellum.
What happens when there is damage to the spinal cerebellar tracts?
Loss of proprioception and coordination to the contralateral limb.
Describe the path of the cuneocerebellar tract
1st order neurones ascend on the ipsilateral side in the cuneocerebellar tract and synapse in the brainstem. After, the neurones travel to the cerebellum where they terminate.
Describe the path of the trigeminal nerves
The nerves run to the trigeminal nucleus (brainstem) where the central processes synapse then they travels up to the thalamus where they synapse with the third order neurones and then run up to the cerebral cortex.
