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Flashcards in Spinal Cord Lesions Deck (26)
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what is complete transection of the SC?

-trauma, ischemia, or pathological processes may partially or completely damage SC
-depending upon the level of the lesion, it may result in either quadriplegia or paraplegia



-caused by transection of the SC b/w levels of C5-6
-results in bilateral paralysis of the upper and lower extremities



-caused by transection of the SC b/w the levels of T1-2
-results in bilateral paralysis of lower extremities


first phase of complete transection of the SC

-immediately following transection of the SC, there is complete suppression of the spinal reflex arcs distal to the lesion--SPINAL SHOCK
-lasts b/w 4 days-6 weeks w/ an average of 2-3 weeks
-loss of all sensations, reflex activity
-bilateral flaccid paralysis of involved extremities
-loss of voluntary control of a spastic urinary bladder
-loss of sexual potency in the male
-various visceral deficits--loss of thermoregulation, causing cool, dry, skin with no sweating
-transient Horner's Syndrome if the lesion is above T2


second phase of complete transection of the SC

-marked by appearance of any spinal reflex activity distal to lesion
-gradually, the isolated SC shows an autonomous activation of the intrinsic spinal circuitry--results in variable and overlapping changes in reflexes and spasticity
-pts at first demonstrate minimal reflex activity and with time, develop spastic paralysis with changes in reflexes
-eventually, spasticity alternates b/w flexor and extensor spasm activity
-later, extensor M spasm or deep reflexes predominate


third phase of the complete transection of SC

-after an interval of 1-2 years, the affected M groups of the paralyzed pt will exhibit tonic M spasms of the extensors or flexors


SC level C1-4 deficit

-trauma to the upper cervical cord may disrupt the phrenic nucleus
-results in respiratory depression or arrest


SC level above T1 deficit

Horner's Syndrome
-lesions of the reticulospinal fibers descending to the interomediolateral (preganglionic sympathetic) cell column at T1
-results in Horner's Syndrome


SC level above T2 deficit

-sweating and vasomotor disturbances of the body


SC level C5-T6 deficit

-"rocking horse" type of respiration
-high thoracic or low cervical damage may disrupt the descending fibers to the MMCC
-resultant paralysis does not allow the intercostal Ms to assist in breathing and the pt mimics this particular mvmt


SC level S2 deficit

-reflex bladder
-lesions of the SC above the level of S2 may result in a reflex or spastic bladder
-although there is not voluntary bladder control, distention of the bladder wall results in a reflex (usually incomplete) voiding of the bladder


SC level S3-5 deficit

-lesions in this region result in flaccid anal sphincter tone with bowel incontinence


Horner's Syndrome

-seen in pts with neuro conditions such as SC injuries or brainstem damage
-may be caused by an interruption of the cervical sympathetic trunk, transection of the SC above the level of T1, or hemisection of the SC (Brown Squared) above the level of T1
-S/S--show up ipsilaterally
-slight ptosis of the upper lid due to paralysis of the tarsal M
-miosis or pupillary constriction due to paralysis of dilator pupillae M
-enophthalmos due to paralysis of the orbitalis M of Muller which has a slight protrusion function
-anhydrosis/blushing with vasodilation--skin on the face due to the loss of sympathetic innervation of the blood vessels


paralytic poliomyelitis

-symptoms seen with poliomyelitis such as fever, headache, vomiting, neck stiffness, and pain in back and limbs can go away and the pt will recover to get (non paralytic poliomyelitis) or it will result in varying degrees of paresis or paralysis (paralytic poliomyelitis)
-may involve damage to the nucleus ambiguus, phrenic nucleus, or medial motor column with resultant paralysis of the pharyngeal, laryngeal, diaphragm, or intercostal Ms
-assoc. problems of airway obstruction and clearance and pulmonary ventilation are life threatening



-seen with UMN paralysis
-refers to a paralysis of the upper and lower extremities on the same side of the body
-usually due to unilateral destruction of the motor cortex, internal capsule, or descending motor tracts above the pyramidal decussation
-results in spastic paralysis or paresis of the upper and lower extremities on the opposite side of the body
-destruction of the descending motor tracts b/w decussation and C5-->results in ipsilateral hemiplegia


vestibular special system

-postural impairment


cerebellar special system

-intention tremor


pyramidal special system

-Babinski reflex
-spastic paralysis
-decorticate rigidity


extrapyramidal special system

-tremors at rest


cortical special system

-focal lesions of primary cortices
-memory impairment
-content of cognition


nonnociceptive afferents in the Gate Control Hypothesis--- alpha and beta fibers

-closes the gate
-diminishes pain


nociceptive fibers in the Gate Control Hypothesis--C fibers

-opens the gate
-enhances the pain


congenital absence of nociceptive C type fibers

-results in disinhibition of the SG cell and an insensitivity to pain
-decrease in C type fibers closes the gate--decreases pain b/c with C type fibers we usually open the gate and enhances pain


Herpes Zoster

-may compromise the nonnociceptive A type fibers which inhibit the SG cells and inc sensitivity to pain
-decrease in A type fibers opens the gate--inc pain b/c with A type fibers usually close gate and diminish pain


Brown Sequard Syndrome

-unilateral transverse lesion or hemisection of the SC
-due to knife/bullet wound
-due to tumor such as meningioma pressing upon cord

-damage to posterior columns--ipsilateral loss of proprioception and vibratory sensations from the body below the level of the lesion
-damage to LCST (descending motor tracts)--ipsilateral spastic paralysis below the level of the lesion
-damage to the LSTT--contralateral loss of pain and temp sensations from the body 2 sensory dermatomal segments below the level of the lesion


subacute combined degeneration and pernicious anemia

-atrophy of the mucosal lining of the stomach results in an absence of intrinsic factor req'd to absorb vit B12
-deficiency in vitamin B12 causes many neuro disorders
-results in macrocytic anemia and degeneration of the posterior columns and pyramidal tracts
-S/S of subacute combined degeneration includes:
-numbness and tingling in fingers/toes--glove and stocking anesthesia
-bilateral loss of proprioception and vibratory sensations
-UMN signs such as spastic paralysis, paresis, hyperreflexia, and Babinski