Spinal Cord Compression Flashcards Preview

Year 3 Clinical > Spinal Cord Compression > Flashcards

Flashcards in Spinal Cord Compression Deck (40)
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1
Q

Main white matter tracts?

A

Motor - corticospinal tracts (located in the lateral white matter)
NOTE - consists of UMNs and LMNs

Sensory :
• Spinothalamic tracts (located in the anterolateral white matter)
• Dorsal columns (located in the posterior / dorsal white matter)
NOTE - consist of 1st, 2nd and 3rd order neurones

2
Q

Difference between grey and white matter?

A

White matter - myelinated axons

Grey matter - cell bodies of neurones

3
Q

Pathway of the corticospinal tract?

A

2 neurones:
• Upper motor neurone (UMN) - runs from the motor cortex to the anterior grey horn; decussation occurs at the level of the medulla

This means it runs IPSILATERAL to the side of the body it supplies but info is received in the contralateral motor cortex

• Lower motor neurons

4
Q

Signs of an UMN lesion?

A

Increased tone, due to loss of inhibition; in the case of an UMN lesion, this is called spasticity

Loss of power (weakness):
• Extensors weaker than flexors in the arms
• Flexors weaker than extensors in the legs

Hyper-reflexia (brisk reflexes)

Babinski sign is present (up-going plantar response),as the UMN of the corticospinal tract is damaged, so other descending pathways dominate

Muscle wasting that is NOT MARKED

No fasciculations

5
Q

Where do UMN lesions occur?

A

Above the anterior horn cell, i.e: spinal cord, brain stem, motor cortex

NOTE - anterior horn cells are the cell bodies of the LMNs; they are located in the anterior grey matter of the spinal cord

6
Q

Features of spasticity that differentiate it from rigidity?

A

It is VELOCITY-DEPENDENT

Present predominantly in:
• FLEXOR muscles and forearm pronators of the ARMS
• EXTENSOR muscles of the LEGS

7
Q

Normal plantar response?

A

Should normally cause toe flexion

Great toe will extend and other toes will fan (Babinski sign) in UMN lesions

8
Q

Signs of a LMN lesion?

A

Decreased tone

Muscle wasting

Fasciculations

Diminished reflexes (hyporeflexia) or areflexia

Babinski sign is absent

9
Q

Where do LMN lesions occur?

A

Either in the anterior horn cell OR distal to the anterior horn cell, i.e: anterior horn cell, root, plexus, peripheral nerve

10
Q

Pathway of the spinothalamic tracts?

A

1st order neurone enters spinal cord and then 2nd order neurone immediately decussates at that spinal cord level

i.e: the tract runs CONTRALATERAL to the side of the body it supplies and info reaches the contralateral sensory cortex

11
Q

Function of the spinothalamic tract?

A

Supplies, to the contralateral side of the body:
• Crude (non-discriminative touch)
• Pain
• Temperature

12
Q

Pathway of the dorsal columns?

A

Decussation occurs at the level of the medulla, so the tract runs on the IPSILATERAL side as the side of the body it supplies

13
Q

Function of the dorsal columns?

A

Supplies, to the ipsilateral side of the body:
• Fine (discriminative) touch
• Proprioception
• Vibration

14
Q

With which tuning fork is vibration sense tested?

A

128Hz

15
Q

Categories of spinal cord compression?

A

Acute VS chronic

Complete (everything is damaged) VS incomplete (some residual motor / sensory function)

16
Q

Causes of acute spinal cord compression?

A

Trauma

Tumours (commonly metastases) can cause haemorrhage or collapse

Infection

Spontaneous haemorrhage

17
Q

Causes of chronic spinal cord compression?

A

Spondylosis (degenerative disease)

Tumours

Rheumatoid arthritis (common cause of cervical instability)

18
Q

Presentation of acute cord transection?

A

This is a complete lesion, i.e: all motor and sensory modalities beyond that point are affected

NOTE - sensory level can be located by checking dermatomes
Motor level can be located by checking myotomes

Initially, they have flaccid areflexic paralysis (AKA spinal shock) below the level of the injury; this is an acute, transient stage of spinal cord lesions and the classic UMN signs appear later

19
Q

Signs of flaccid arreflexic paralysis?

A

Hypotonia; muscles become flaccid and cannot contract

Areflexia

20
Q

What is Brown-Sequard syndrome?

A

Incomplete spinal cord injury that occurs due to cord hemisection, i.e: injury to one side of the spinal cord

This results in symptoms on the:
• Ipsilateral motor level (as the CST runs on the ipsilateral side)
• Ipsilateral dorsal column sensory level
• Spinothalamic sensory level

21
Q

Symptoms of Brown-Sequard syndrome?

A

Ipsilateral motor level - loss of motor function on the ipsilateral side (as the lesion)

Ipsilateral dorsal column sensory level - loss of the following on the ipsilateral side:
• Fine touch
• Proprioception
• Vibration

Contralateral spinothalamic sensory level - loss of the following on the contralateral side:
• Coarse touch
• Pain
• Temperature

22
Q

What is central cord syndrome?

A

Most common form of incomplete spinal injury;

Mainly caused by hyperflexion or extension injury to an already stenotic neck

23
Q

Symptoms of central cord syndrome?

A

Main symptom is DISTAL UPPER LIMB WEAKNESS:
• Complete paralysis of hands
• Weakness at wrists
• Able to move elbows and shoulders

PRESERVATION OF LOWER LIMB POWER

‘Cape-like’ spinothalamic sensory loss (of coarse touch, pain and temperature in this distribution)

Functions of dorsal column are preserved

24
Q

How does the somatotopic organisation of the anterior horn cells relate to the pattern of weakness in central cord syndrome?

A

Only the central part of the spinal cord is damaged

As the anterior horn cells corresponding to the hands are most central, they suffer complete paralysis

As the anterior horn cells corresponding to the elbows and shoulder are more lateral, function is partially preserved

As the anterior horn cells corresponding to the legs are most lateral, function is completely preserved, as this area of the spinal cord is undamaged

ADD IMAGE

25
Q

Why do patients suffer STT sensory loss when the STT is very laterally located in the spinal cord?

A

Despite being laterally located, the 2nd order neurones of the STT decussate at spinal cord level, so these are damaged

26
Q

Presentation of chronic spinal cord compression?

A

Same as acute compression

BUT

UMN signs predominate, as there is no period of acute flaccid areflexic paralysis

27
Q

Trauma that can cause spinal cord compression?

A

Typically a high-energy injury, e.g: RTA

Mobile segments of the spine are esp. vulnerable, i.e: CERVICAL

28
Q

Types of tumour with relation to the spinal cord?

A

Extradural - usually METASTASIS; commonly from lung, breast, kidney, prostate

Intradural - i.e: within the spinal canal; there are 2 types:
• Extra-medullary - meningioma, schwannoma
• Intra-medullary - astrocytoma, ependymoma

29
Q

Effects of tumours on the spinal cord?

A

Can cause:
• Slow compression
OR
• Acute compression via collapse or haemorrhage

30
Q

Why does spinal canal stenosis occur?

A

Osteophyte formation

Bulging of intervertebral discs

Facet joint hypertrophy

Subluxation

31
Q

How do epidural abscesses occur?

A

Bloodborne infection (often Staph.)

Surgery or trauma

Tuberculosis of the spine (esp. in endemic countries or with travel to those countries)

32
Q

Types of haemorrhage affecting the spine?

A

Epidural

Subdural

Intramedullary

33
Q

Causes of haemorrhage?

A

Trauma

Bleeding diatheses / disorders

Anti-coagulants

AVMs

34
Q

Treatment of spinal trauma?

A

ABCDE + IMMOBILISATION

Follow with Ix

Decompress and stabilise the spine using:
• Surgery
• Traction
• External fixation

Giving methylprednisolone is a historic treatment

35
Q

Ix for spinal trauma?

A

X-ray or CT or MRI

36
Q

Treatment of metastatic tumours?

A

Depends on patient and tumour; often have a poor prognosis, so treatment is mainly for relief from symptoms

Dexamethasone (also used acutely) helps preserve spinal cord function

Radiotherapy

Chemotherapy

Surgical decompression of the cord and stabilisation (mainly in younger patients)

37
Q

Treatment of primary tumours of the spine?

A

Surgical excision

38
Q

Treatment of infection of the spine?

A

Antimicrobial therapy
Surgical drainage

If required, stabilisation

39
Q

Treatment of haemorrhage at the spine?

A

Reverse anti-coagulation

Surgical decompression of the cord

40
Q

Treatment of degenerative disease of the spinal cord, e.g: spondylosis?

A

Surgical decompression +/- stabilisation

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