Four limb weakness Flashcards
What produces UMN signs and what are they?
Lesions to the brain, brainstem and spinal cord
Bulk - normal Tone - Increased Power - reduced Abnormal movement - fasciculations not seen Reflexes - Brisk Plantar/Babinski - Up-going Clonus - +ve
What produces LMN signs and what are they?
Lesions to the LMN, anterior horn cell nerve root or peripheral nerve
Bulk - atrophy Tone - decreased Power - reduced Abnormal movement - fasciculations Reflexes - decreased/absent Plantar/Babinski - down-going Clonus - -ve
When can mixed UMN and LMN signs occur?
MND
B12 deficiency
taboparesis
What is spinal shock?
When someone has an acute insult to the cord (vascular, trauma, haemorrhage) it can cause LMN features
What tracts are affected in anterior cord syndrome?
- Lateral corticospinal tracts
* Lateral spinothalamic tracts
What are the features of anterior cord syndrome?
Bilateral loss below level of lesion: o Motor function o Light touch o Pain o Temperature
What are the features of central cord syndrome?
MUD-E • Motor > sensory • Upper extremity > lower extremity • Distal > proximal • Extension injury
What tracts are affected in hemi-cord/Brown-Sequard syndrome?
- Lateral corticospinal
- Dorsal columns
- Lateral spinothalamic
What are the features of hemi-cord/Brown-Sequard syndrome?
Ipsilateral loss below lesion
o Motor function – spastic paraparesis
o Proprioception – sensory ataxia
o Vibration
Contralateral loss below lesion – spinothalamic tract decussates
o Pain
o Temperature
What is subacute combined degeneration of the spinal cord?
Vitamin B12 or E deficiency causing degeneration of the posterior and lateral columns of the cord
What tracts are affected in subacute combined degeneration of the spinal cord?
- Lateral corticospinal
- Doral columns
- Spinocerebellar
What are the features of subacute combined degeneration of the spinal cord?
Bilateral: o Motor – UMN signs o Proprioception and vibration o Limb ataxia o Absent ankle and knee jerks
What is Friedrich’s ataxia and what symptoms does it produce?
Inherited condition
Same symptoms as subacute combined degeneration of the spinal cord with an intention tremor
What is syringomyelia and what is it associated with?
Fluid-filled cyst forms within the spinal cord causing compression due to dilation of CSF space within spinal cord
Chiarai 1 malformation
What does syringomyelia affect in the spinal cord?
- Ventral horns
* Lateral spinothalamic
What are the features of syringomyelia?
- LMN signs
* Cape-like Bilateral Loss of pain and temperature
What does neurosyphilis cause?
Degeneration of dorsal columns:
• Loss of proprioception and vibration
What does compression of C5 and above cause?
- UMN signs
- Sensory loss in all 4 limbs
- Diaphragmic weakness
- Autonomic dysfunction - incontinence
What does compression of C5-T1 cause?
- LMN signs in upper limbs
- Sensory loss below level of lesion
- UMN signs in legs
- Respiratory (intercostal) weakness
- Autonomic dysfunction – urinary incontinence
What does compression of thoracic vertebrae cause?
- Spastic paraplegia
- Sensory level on trunk
- Weakness of legs
- Sacral loss of sensation
- Extensor plantar responses
What does compression of Cauda equina/below T12/L1 above cause?
- LMN signs
- New onset bilateral sciatica
- New/worsening Back pain
- Saddle area anaesthesia
- Decreased anal sphincter tone
- Urinary retention
What can cause acute transverse myelitis?
inflammation of the spinal cord
Inflammatory
o MS, post-infective, NMO/Devic’s
o CTD related (lupus, sjogren’s, sarcoid)
Compressive
o Discs, tumours
Infective o Viral (HZV, HIV)
Metabolic
o B12, copper deficiency
What is GBS?
B-cells produce antibodies against a pathogen that target myelin sheath, motor nerve cell or axon
What is the presentation of GBS?
- Peripheral loss of sensation or neuropathic pain
- Symmetrical ascending weakness (starting at the feet and moving upwards)
- Reduced reflexes
What are the other features of GBS?
- Hx gastroenteritis
- Respiratory muscle weakness
- CN involvement
- Autonomic involvement
What do nerve conduction studies and lumbar puncture show for GBS?
Nerve conduction studies:
o Slow motor nerve conduction velocity (demyelination)
o Prolonged/absent F waves
o Prolonged distal motor latency
Lumbar puncture
o Increased protein
o Normal WBC count and glucose
How do you manage GBS?
- IV immunoglobulins
- Plasma exchange
- Supportive care
- VTE prophylaxis
What is miller fisher syndrome and how does it present?
Variant of Guillain-Barre syndrome
Descending paralysis:
• Ophthalmoplegia
• Areflexia
• Ataxia
What is Charcot-marie-tooth disease
AD peripheral neuropathy
- LMN and sensory signs
What is MND?
Progressive degeneration of UMN and LMN
No sensory loss of sphincter distrubance
What is Amyotrophic lateral sclerosis (ALS)?
Loss of motor neurones in motor cortex and anterior horn of the cord
o LMN signs in arms UMN signs in legs
What is Progressive bulbar palsy?
Palsy of tongue, muscles of mastication and facial muscles
o Loss of brainstem motor nuclei (IX-XII)
What is Progressive muscular atrophy?
Anterior horn cell lesion
o LMN signs only
What is Primary lateral sclerosis?
Loss of Betz cells in motor cortex
o UMN signs only
