Spine Flashcards
(21 cards)
Lateral Corticospinal Tract
Fine movement in distal limbs
Path: Motor cortex > Internal capsule > Ipsilateral anterior brainstem
Crossess Midline (Decussate) in lower medulla
Terminate: on anterior horn motor neurons that supply UE/LE muscles
Lesion: Above & below medulla
Rubrospinal Tract
Support Roll of latereal corticospinal tract; promotes UE flexos and inhibits UE extensors
Pathway: crossess the ventral tegmental decussation :crossess immediately; decends in latereal column of spinal cord just anterior to the lateral corticospinal tract
Lesion: As isolated spinal cord lesion is RARE
Decerebrate
Brainstem Damage involving the red nucleus and below
– Red Nucleus damage decreases UE flexor tone and allows UE extension tone to dominate at the elbow
Decorticate
Brainstem damage “above” the red nucleus; UE flexor tone
Anterior Corticospinal Tract
Control and maintain axial/ proximal limb voluntary movements
Pathway: Doesnt cross midline in medulla; decends in anteromedial spinal cord
Terminates near medial ventral horn of most levels of spinal cord
Tectospinal
Function: Head & Eye movements
Pathway: originates in superior coliculi; crossess imediatelely; cervical spine supplies postureal muscles head and neck
Reticulospinal Tract
Function: Modulates reflexive/ autonomic motor movements related to gait posture; reticular system modulates flexor response
Pathway: reticular nuclei of lower 2/3 of brainstem
Terminates on motor nuclei of the anterior horn in all levels of spinal cord
Vestibulospinal Tract
Function: control head and neck movement/posture
Pathway: begins medial vestibular nuclei of medulla; decends in anteromedial spinal cord bilaterally
Terminates on motor nuclei of the neck muscles located in the anterior horn in all levels f spinal cord
Phase 1: Areflexia/hyporeflexia
Immediate areflexia/hyporeflexia occurs
Phase 2: Initial reflex return
The first reflex to return in the bulbocavenous reflex typically returns within 24-48 hours after injury; end of spinal shock
Phase 3: Initial hyperrreflexia
Some DTR begin return 1-4 weeks after the injury and become hyper-reflexic
Phase 4: Final hyperreflexia
Occur when all DTR below the level of injury have returned to and are hyper reflexive; flaccid paralysis is replaced by hypertonicity/spasticity during the 1-12 months after months after the injury
Brown Sequard Syndrome
incomplete lesion; ipsilateral loss of proprioception, discriminating touch and vibration below level of injury; Miscellaneous. Penetrating injury
Anterior Cord Lesion
Incomplete Lesion- anterior 2/3 cord is damaged
Bilateral motor loss below level of lesion & bilateral pain/temp
Miscellaneous: Poor prognosis for ambulation and bowel and bladder functions
Mechanism: Associated with flexion injuries; vascular occulsion to anterior artery
Posterior Cord Lesion
Incomplete lesion- posterior column damaged
Remains intact
No loss of pain/temp; bilateral loss of proprioception, discriminating touch and vibration below level of lesion; clinical- positive rhomberg test
Miscellanous- Most infrequent syndrome
Mechanism of injury: Hyperextension injuries; disc compression, posterior spinal artery occulsion
Central Cord Lesion
Incompete Lesion- area around central canal of the cord is damaged; impaired spinothalamic tracts as they cross midine
No motor loss
Cervical loss of pain/temp in classic cape distribution of upper extremity; no loss of proprioception, discriminating touch vibration
Transverse Cord Lesion
Complete lesion all white and grey matter damage
Bilateral motor loss between lesion
Bilateral loss of proprioception, discriminating touch and vibration below level of lesion
Pain Modulation Ascending Pathway
Periaqueductal grey area, raphe nuclei and other reticular nuclei
Lateral Vestibulospinal Tract
Maintain balance and extensor tone
descends in anteromedial spinal cord
