JC31 (Surgery) - Diseases of Spinal Cord

Question 1

Acute causes of paraplegia

Answer 1

Trauma (commonest)
Transverse myelitis
Acute cord compression
Infective – viral myelitis, abscess, spondylodiscitis
Vascular – spinal infarct, vascular malformation

Question 2

Chronic causes of paraplegia

Answer 2

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

Question 3

Complete cord lesion

• Features
• Associated causes

Answer 3

Question 4

Dorsal cord lesion

• Features
• Associated causes

Answer 4

Question 5

Anterior cord lesion

• Features
• Associated causes

Answer 5

Question 6

Hemi-cord lesion

• Features
• Associated causes

Answer 6

Question 7

Central cord lesion

• Features
• Associated causes

Answer 7

Bilateral spinothalamic loss at the level

Long tract- sacral sparing, UL>LL weakness

Question 8

Conus medullaris and cauda equina lesion

• Features
• Associated causes

Answer 8

Question 9

Define spinal** (not neurogenic) shock and recovery phase

Answer 9

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

Question 10

Define neurogenic shock and associated s/s

Answer 10

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)

Question 11

List anogenital dysfunctions due to spinal cord lesion

Answer 11

Spastic/ Neurogenic bladder (complicated by UTI, reflux nephropathy)

incontinence ± constipation

sexual dysfunction

Question 12

List all autonomic problems due to spinal cord lesion

Answer 12

• *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

Question 13

Differentiate the patterns of pain due to bone, spine or radicular lesion

Answer 13

• 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

Question 14

First line investigations for suspected spinal cord lesion

Answer 14

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

Question 15

D/dx acute cord compression

Answer 15

Disc prolapse
Infections – TB/pyogenic abscess
vertebral collapse
Trauma
Cancer: met CA, lymphoma, myeloma
Haematoma: spontaneous, traumatic

Question 16

3 anatomical locations of spinal cord tumors

Answer 16

□ Extradural: majority metastatic
□ Intradural extramedullary: meningioma and nerve sheath tumours
□ Intramedullary: gliomas, incl. ependymomas and astrocytomas

Question 17

Extradural metastatic tumors

• Common primaries
• Which section of spine
• Routes of metastasis to spine
• Presentation

Answer 17

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)

Question 18

Radiographic features of extradural tumors

Answer 18

Plain XR: osteolytic lesions, vertebral collapse, pedicle erosion

MRI of entire spine: confirm extradural compressive lesion

Question 19

Management outline for extradural tumors

Answer 19

→ Dexamethasone 4mg IV Q6H if neurological symptoms present

→ Surgical decompression + stabilization followed by RT if unstable

→ RT alone if stable spine OR unfavourable prognosis

Question 20

List examples of Intradural-extramedullary and intramedullary tumors

Answer 20

Intradural extramedullary: meningioma and nerve sheath tumours (e.g. schwannoma)

Intramedullary: gliomas, incl. ependymomas and astrocytomas

Question 21

Compare spinal meningioma vs schwannoma

• Type of spinal cord tumor
• Location
• Associated syndrome

Answer 21

Both are Intradural- Extramedullary tumors

 Spinal meningioma: slow-growing, invasive intradural extramedullary lesions ± bone erosions

 Spinal schwannoma: usually cervical or lumbar intradural extramedullary lesions

Both associated with Neurofibromatosis type II (give multiple lesions)

Question 22

Name 2 Intramedullary gliomas

Answer 22

Spinal ependymoma: commonest intramedullary SC tumours in adult

Spinal astrocytoma: 2nd most common primary cord tumour

Question 23

Define syringomyelia

Typical Site

Answer 23

Syringomyelia: acquired development of a cavity (syrinx) within central spinal cord

Site: usually in lower cervical but may extend upward to brainstem (syringobulbia) or downward to filum terminale

Question 24

Causes of syringomyelia

Answer 24

Causes:
□ Arnold-Chiari malformation: cerebellar tonsils obstructs foramen magnum → impaired drainage

□ Dandy-Walker malformation

□ Acquired spinal cord pathologies: trauma, arachnoiditis, intramedullary tumour

Question 25

Presentation of syringomyelia

Answer 25

Presentation: central cord pattern □ Suspended, dissociated sensory loss: → Loss of pain and temperature alone in cape-like distribution → Classically associated with painless burns □ Anterior horn involvement → Wasting and weakness of small hand muscles → Winging of scapula → Scoliosis □ ± long tract signs □ ± brainstem signs, due to syringobulbia or Chiari malformation □ ± hydrocephalus (25%), usually asymptomatic

Question 26

Ix and Mx of syringomyelia

Answer 26

Mx: □ Syringostomy to drain syrinx into CSF space □ Syringoperitoneal shunt □ Decompression of underlying Chiari malformation

Question 27

Outline the topographic map of spinal tracts

Answer 27

Question 28

UMN vs LMN lesion differences

Answer 28

Question 29

List all spinal myotome levels

Answer 29

Question 30

Outline the tracts of DCML and Spinothalamic tract

Answer 30

Question 31

Outline all dermatomal landmarks

Answer 31

Question 32

Define the lesion types at conus medullaris and cauda equina

Answer 32

Question 33

Bloody supply to spinal cord

Answer 33

Question 34

Describe the course and origins of spinal arteries

Answer 34

Question 35

Horner syndrome 4 features

Answer 35

Question 36

S/S foramen magnum lesion

Answer 36

Question 36

S/S thoracic and Lumbar spine lesion

Answer 36

Question 37

S/S conus and cauda equina lesion

Answer 37

Question 38

S/S cervical spine lesion

Answer 38

Question 39

ASIA classification of Spinal cord injury

Answer 39

Question 40

Ddx etiologies of spinal cord lesion - VINDICATE \*\*\*\*\*\*\*\*

Answer 40

Vascular - SC infarct (AAA, Aorta surgery), Spinal cord AVM Infection - Spinal abscess, tuberculosis, osteomyelitis… Inflammation - Transverse myelitis, MS Neoplasms Degenerative - Spondylosis (disc degeneration/ prolapse; apophyseal joint damage' joint hypertrophy' SC canal stenosis) Congenital defects: Spinal bifida occulta, Meningocele, Myelomeningocele

Question 41

Routes of spinal metastasis

Answer 41

Hematological Direct (e.g. lung CA) Lymphatics Subarachnoid seeding via CSF from CNS cancer

Question 42

List examples of extradural, intradural extramedullary and intramedullary spinal tumors

Answer 42

Extradural - Spinal metastasis Intradural extramedullary - Meningioma, Schwannoma Intramedullary - Spinal ependymoma, Spinal astrocytoma

Question 43

Name the 1st and second most common primary\*\* spinal cord tumors

Answer 43

Question 44

Treatment and intra-operative monitoring methods for spinal cord tumors

Answer 44

Surgical resection +/- External RT adjuvant therapy - primary tumor Palliative surgery (pain, instability…) - Metastatic tumors Monitoring: Motor Evoked Potential (MEP) and Somatosensory Evoked Potential (SSEP)

Question 45

Sponylosis and and myelopathy Management - Conservative and surgical

Answer 45

Conservative - Physiotherapy, Analgesics Surgical decompression - Progression neurological deficit, Myelopathy, Radiculopathy, Intractable pain

Question 46

Tethered cord syndrome * Cause * Associated condition * S/S * Tx

Answer 46

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

Question 47

Spinal cord trauma * common causes * Common location of traumatic damage * Types of spinal trauma

Answer 47

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

Question 48

Difference in presentation between small and large central cord lesion

Answer 48

Question 49

Causes of myeloneuropahty

Answer 49