CC2: spinal cord disorders Flashcards
What is myelopathy?
-Disease or damage to spinal cord causing any neurologic deficit
-Major cause of disability
What are some symtoms of myelopathy?
-motor deficits and primary sensory deficits and distrubances that localize a spinal cord level
1.weakness, ataxia (usually bilateral)
-signs of autonomic dysfunction
1. bladder/bowel disturbance
2. orthostatic hypotension, sexual dysfunction
Where does decussation of spinothalamic fibers occur?
spinal cord (contralateral pinprick pain/temperature deficit
Where does decussation of dorsal colu,ms/medial lemniscus fibers occur?
medulla (Ipsilateral propioception/vibration deficit)
where is the lower motor neuron located?
anterior horn cells
where is the upper motor neuron located?
lateral corticospinal tract
Findings of lower motor neuron?
Hyporeflexia, decreased tone, fasciculations (fine twitching of muscles), atrophy
Findings of upper motor neuron?
Hyperreflexia, spasticity, Babinski reflex(corticospinal tract lesion sign
which reflexes are affected with spinal cord lesions?
-abdominal cutaneous reflexes
-cremasteric reflex
-anal wink
-bulbocavernous reflex
What is the transverse cord lesion?
-all sensory /motor pathways partially or completely interrupted [trauma tumors, myelitis)
What is hemicord lesions: brown-sequard syndrome?
Damage to lat. corticospinal tract: ipsilateral upper motor neuron deficits below level of lesion
Damage to anterior horn cells: ipsilateral lower motor neuron deficits at level of lesion
Damage to posterior columns: ipsilateral loss of position and vibration sense
Damage to anterolateral (spinothalamic) system- contral. loss of pain and temperature sensation
What is central cord syndome?
-If small lesions, spinothalamic fibers crossing affected:
bilateral regions of suspended sensory loss in pain and temperature- may be asymmetric!
-If large lesions, anterior horn cells, corticospinal tract, posterior columns also affected:
1. lower motor neuron deficits at level of lesion
2. upper motor neuron deficit below level of lesion
3. Loss of propioception and vibration below the level
What is posterior cord syndrome?
Lesion of posterior column: loss of propioception and vibration below level
With large lesion, may affect lat. corticospinal tract: upper motor neuron deficits
(syphillis or vit 12 defficiency
What is anterior cord syndrome?
Damage to anterolateral (spinothalamic) system: decreased pain and temperature below lesion
Damage to anterior horn cells: lower motor neuron deficits at level of lesion
If large, damage to corticospinal tract: upper motor neuron deficits below level of lesion
What is cervical spondylotic myelopathy?
Spinal stenosis and compression of spinal cord resulting from age-related degenerative changes of the spine
surgery to decompress the spinal cord
What is the initial phase of trauma of spinal cord?
due to injury, spinal shock flaccid paralysis, los of DTRs
explain anterior spinal artery infarct
most commonly caused by insufficiencies within aorta
aneurysms, dissections, surgery, atherosclerosis…
-bilateral loss of motor fx, pain/temperature sensation/-relative sparing of proprioception and vibratory senses below the level of the lesion
- acute stage with spinal shock
Treatment:
-hypothermia, CSFdrainage, revascularization of Artery of Adamkiewicz under investigation when affected
-ASA
Prevention: identification of Artery of Adamkiewicz prior to thoracoabdominal aortic repairs
explain vitamin b12 deficiency
Myelopathy causing ataxia from affected dorsal columns and weakness from affected lateral corticospinal tract- subacute combined degeneration
-often not a result of poor diet, a result of poor absorption often occurring with age
-Treatment: vitamin B12 replacement
exaplain neurosyphilis tabes dorsalis
Chronic slowly progressive myelopathy causing ataxia from affected dorsal columns accompanied by pain from affected dorsal nerve roots
Treatment: Penicillin G
explain inflammatory myelitis
-Can be idiopathic or secondary to multiple sclerosis, neuromyelitis optica, connective tissue diseases, or sarcoidosis
-Acute or subacute myelopathy
Tx: steroids, immunosuppressant drugs
What is metastatic myelopathy?
metastatic spread to epidural space most common
metastatic spread to vertebral bodies
80% of patients treated after they loose ambulation will remain nonambulatory, 80% of patients treated before loosing ambulation will remain ambulatory for the rest of their lives.
Tx: Radiation and/or sugery
What is spina bifida myelomeningocele?
The most severe type of spina bifida- portion of the neural tube fails to develop or close properly in babies, causing defects in the spinal cord and in the bones of the spine.
Limb deformities , weakness, sensory disturbances , bowel and bladder problems, hydrocephalus
Treatment- surgery
3 important nerve roots in the arm?
C5, C6, C7 (most common in radiculopathies)
3 important nerve roots in the leg
L4, L5 (most common), S1 (most common)
What is a radiculopathy?
Sensory or motor dysfunction caused by a spinal nerve root lesion
a type of neuropathy
most commonly caused by disc herniation (C6,C7, L5, S1 most common)
Other causes: degenerative disease of vertebra/ligaments of spine, diabetes, metastasis, Guillain- Barre syndrome, herpes zoster
what are some signs and symptoms of radiculopathy?
-Burning, tingling pain that radiates or shoots down a limb in dermatome of affected nerve root
-Sensation may be diminished in dermatome of affected nerve root
-Loss of reflexes, and motor strength in radicular distribution(following dermatome)
-If chronic, atrophy and fasciculations (fine twitching of muscle)
How can radiculopathies be evaluated?
-Straight leg raising test may be helpful in diagnosis of mechanical nerve root compression in lumbosacral region
1. reproduction pain and abnormal sensation (paresthesias)
-Flexing or turning head toward affected side for cervical root compression
1. reproduction of pain and abnormal sensation (paresthesias)
-Percussion of spine
Imaging, nerve conduction studies, labs
how can we treat radiculopathies?
Treatment:
NSAIDS or oral steroids for inflammatory process
General pain management and for neuropathic pain- antiepileptic drugs, tricyclic antidepressants
physical therapy
nerve root block injections- i.e., epidural steroid injections
surgical option to decompress root for persistent or progressive pain and disability from compressive etiologies
Discectomy
Artificial disc replacement
Laminectomy
Spinal fusion
Radiation if bone metastasis
For infectious causes- Acyclovir for Herpes Zoster,Gancyclovir for CMV
which is the most common cause of rediculopathies?
herniated discs, in c6, c7, l5, s1
what is cervical herniated discs?
constricted by posterior longitudinal ligament to herniate laterally toward nerve root.
nerve root invovled usually corresponds tot he lower if the adjacent two vertebrae
what is lumbosacral herniated discs?
-posterolateral herniations more common
-nerve root invovled usually corresponds to the lower of the adjacent two vertebrae
What is spondylosis?
another cause of radiculopathies; Degenerative disc disease leads to bone over bone trauma leading to formation of osteophytes that may compress nerve roots
how deos herpes zozster relate to radiculopathies?
Reactivation of varicella zoster virus
persists for life in the sensory ganglia after initial systemic infection (chickenpox)
Dermatomal rash (shingles) associated with severe radiating pain
Most common in thoracic region
About 1/5 develop a chronic postherpetic neuralgia
Prevention with vaccine- Shingrix Treatment: acyclovir, NSAIDS, narcotics, calamine, tricyclic antidepressant and antiepileptic drugs
How is diabetic radiculopathy?
-One type of rare diabetic neuropathy
-Usually involves the thoracic region with severe pain and dysesthesias along chest and abdominal wall, sometimes weakness of abdominal wall confused with hernia, and sometimes weight loss
-Usually good prognosis with good recovery within a yr.
explain guillain barre in radiculopathies
Common cause of acute flaccid paralysis
Autoimmune , causing a rapidly progressive neuropathy with a predilection for nerve roots
Often but not always preceded by a viral illness
-Campylobacter jejuni enteritis
-HIV infection
Typically presents with progressive ascending weakness , loss of deep tendon reflexes, tingling sensation of hands and feet, and pain that may be radicular
-Motor involvement generally more than sensory involvement- several variants
What is cauda equina syndrome?
Impaired function of multiple nerve roots below L1-L2 spine level
-Sensory deficit S2-S5, saddle anesthesia
-Lumbosacral radicular pain
-leg weakness with decreased tone, hyporeflexia, muscle twitching
-Bladder dysfunction, decreased rectal tone, loss of erections
-loss of anal wink /bulbocavernous reflex as seen with spinal cord lesions
Causes: compressive-central disc herniation, epidural metastasis, lumbar spinal stenosis, trauma, noncompressive- sarcoidosis, cytomegalovirus
Consider a conus medullaris syndrome
-similar deficits with sacral spinal cord lesion but with Babinski sign, hyperreflexia
Neurologic emergency-
