Spinal Cord Flashcards
What sections of spinal cord have ventral enlargements?
Cervical (C5 - T1) - brachial plexus
Lumbar (L1 - S3) - sacral plexus
What sections of spinal cord have intermediate horns?
Thoracic and upper lumbar (T1 - L2)
Rexed’s Laminae:
What nuclei are in Lamina I?
What neurons are here?
Marginal layer or posteromarginal nucleus
Nociceptive (pain) neurons
Rexed’s Laminae:
What nuclei are in Lamina II?
What neurons are here?
Substantia gelatinosa
Interneurons
Rexed’s Laminae:
What nuclei are in Lamina III, IV and V?
What neurons are here?
What is special about Lamina V?
Nucleus proprius
Non-noxious (non-painful) stimuli
Lamina V has wide range
Rexed’s Laminae:
What neurons are lateral?
What neurons are medial?
Lateral - corticospinal and rubrospinal
Medial - afferent from muscle spindles
Rexed’s Laminae:
What nuclei are in Lamina VII?
What neurons are here?
Nucleus dorsalis, Clarke’s nucleus, interomediolateral nucleus
ND&C - non-noxious joint receptors from manipulation of joints (proprioception)
IML - noxious and complex properties (sympathetic T1 - L2)
Rexed’s Laminae:
What neurons are in Lamina VIII?
Wht do they do?
Interneurons
Noxious and complex properties
Rexed’s Laminae:
What neurons are in Lamina IX?
Alpha motor neurons
What is the general somatotopy of the ventral horn?
Medial - proximal muscles
Lateral - distal muscles
Ventral - extensor muscles
Dorsal - flexor muscles
Where are upper motor neuron cell bodies located?
Where do their axons cross the neural axis?
Cerebral cortex and brainstem
Decussation of pyramids
Where are lower motor neuron cell bodies located?
Where do they exit the spinal cord?
Where to they synapse next?
Ventral horn of spinal cord
Ventral root and join spinal nerves
On skeletal muscle at NMJ
List the following characteristics for an upper motor neuron lesion: Paralysis Reflexes Muscle tone Muscle power Atrophy Speed Area Babinski
Spastic Hyper-reflexia Increased Weak Disuse Decreased Large Positive
List the following characteristics for an upper motor neuron lesion: Paralysis Reflexes Muscle tone Muscle power Atrophy Speed Area Babinski
Flaccid Hypo-reflexia or areflexia Reduced with fasciculation Very weak Pronounced Lost Localized Negative
