CNS - Diseases of Spinal Cord Flashcards
Acute causes of paraplegia
Trauma (commonest)
Transverse myelitis
Acute cord compression
Infective – viral myelitis, abscess, spondylodiscitis
Vascular – spinal infarct, vascular malformation
Chronic causes of paraplegia
Spondylotic myelopathy*
Primary or secondary tumours*
Congenital/developmental – syringomyelia, spinal dysarthrism, hereditary spastic paraplegia, Friedrich’s ataxia
Inflammatory – MS, radiation myelopathy, paraneoplastic myelopathy
Degenerative – MND, spinocerebellar ataxia
Subacute combined degeneration
Complete cord lesion
- Features
- Associated causes
Dorsal cord lesion
- Features
- Associated causes
Anterior cord lesion
- Features
- Associated causes
Hemi-cord lesion
- Features
- Associated causes
Central cord lesion
- Features
- Associated causes
Bilateral spinothalamic loss at the level
Long tract- sacral sparing, UL>LL weakness
Conus medullaris and cauda equina lesion
- Features
- Associated causes
Define spinal** (not neurogenic) shock and recovery phase
Spinal shock precede UMN signs for rapidly progressive spinal cord damage :
flaccid paralysis and areflexia for 1-2w after acute event
Recovery: gradual return of function with hyperreflexia (in months)
→ return of anal tone/reflex
→ Any remaining neurological dysfunction at this stage likely permanent
Define neurogenic shock and associated s/s
Neurogenic (spinal) shock in SCI down to T1
→ Cause: sympathetic signal disruption
→ Presentation: vasodilatation → hypotension, bradycardia, warm, flushed skin
- Diaphragmatic breathing if C5 or below (loss of control of intercostal muscles)
- Respiratory arrest if above C3 (loss of control of diaphragm)
List anogenital dysfunctions due to spinal cord lesion
Spastic/ Neurogenic bladder (complicated by UTI, reflux nephropathy)
incontinence ± constipation
sexual dysfunction
List all autonomic problems due to spinal cord lesion
- *Autonomic dysreflexia** (if lesion at or above T6) due to episodic autonomic fluctuation
- S/S: paroxysmal HTN, throbbing headache, excessive sweating, flushing of skin, bradycardia, anxiety etc
Impaired thermoregulation
Differentiate the patterns of pain due to bone, spine or radicular lesion
- Bone pain: continuous, dull pain w/ tenderness over affected area
- Spinal: continuous, deep aching pain radiating into whole leg or half of body; not affected by movement
- Radicular: severe, sharp, shooting, burning pain radiating to dermatome or myotome; exacerbate by mov’t, straining or cough
First line investigations for suspected spinal cord lesion
Clinical evaluation:
- History: Weakness, sensory loss, sphincter disturbance, pain, Temporal course and spatial distribution
- P/E: Motor by myotome, Sensory by dermatome, Cerebellar
Investigations:
- Plain XR spine
- Contrast MRI spine: acute paraplegia
- Myelography/ CT myelography (c/o MRI)
- CSF analysis: transverse myelitis
- Vitamin B12: Subacute combined cord degeneration
D/dx acute cord compression
Disc prolapse
Infections – TB/pyogenic abscess
vertebral collapse
Trauma
Cancer: met CA, lymphoma, myeloma
Haematoma: spontaneous, traumatic
3 anatomical locations of spinal cord tumors
□ Extradural: majority metastatic
□ Intradural extramedullary: meningioma and nerve sheath tumours
□ Intramedullary: gliomas, incl. ependymomas and astrocytomas
Extradural metastatic tumors
- Common primaries
- Which section of spine
- Routes of metastasis to spine
- Presentation
Primaries: commonly breast, lung, prostate, NHL, MM, RCC
Site: 90% at thoracic spine**
Routes: haematogenous, direct invasion (eg. paraspinal CA lung), lymphatics (along root sleeves), subarachnoid seedings
Presentation:
- bone pain and tenderness
- motor/sensory symptom
- sphincter disturbance (late)
Radiographic features of extradural tumors
Plain XR: osteolytic lesions, vertebral collapse, pedicle erosion
MRI of entire spine: confirm extradural compressive lesion
Management outline for extradural tumors
→ Dexamethasone 4mg IV Q6H if neurological symptoms present
→ Surgical decompression + stabilization followed by RT if unstable
→ RT alone if stable spine OR unfavourable prognosis
List examples of Intradural-extramedullary and intramedullary tumors
Intradural extramedullary: meningioma and nerve sheath tumours (e.g. schwannoma)
Intramedullary: gliomas, incl. ependymomas and astrocytomas
Outline the topographic map of spinal tracts
UMN vs LMN lesion differences
List all spinal myotome levels
Outline the tracts of DCML and Spinothalamic tract
Outline all dermatomal landmarks
Define the lesion types at conus medullaris and cauda equina
Bloody supply to spinal cord
Describe the course and origins of spinal arteries
Horner syndrome
4 features
S/S thoracic and Lumbar spine lesion
S/S conus and cauda equina lesion
S/S cervical spine lesion
ASIA classification of Spinal cord injury
Name the 1st and second most common primary** spinal cord tumors
Tethered cord syndrome
- Cause
- Associated condition
- S/S
- Tx
Cause
- Congenital malformation of cord, Spina Bifida Occulta causes lower spinal cord to become anchored by Fatty Filum Terminale or Lipoma
>> Entire SC dragged down and under tension, Low-lying conus medullaris
S/S
- Lower limb spastic weakness, Sphincter dysfunction, Pain, Scoliosis, Foot deformity;
- Worse symptoms at growth spurt
Tx- Surgical untethering
Spinal cord trauma
- common causes
- Common location of traumatic damage
- Types of spinal trauma
Causes:
RTA, Falls, Assault, Sports, Recreation…etc
Most common location: Cervical spine (highest mobility)
Types:
- Vertical compression
- Hinge injury - Intact ligament = stable; Torn ligament = unstable
- Shearing injury
Difference in presentation between small and large central cord lesion
Causes of myeloneuropahty
S/S foramen magnum lesion
