Disorders of the Spine and Spinal Cord Flashcards
What are intrinsic spinal cord disorders?
These are diseases that interfere with spinal cord function due to non-compressive involvement of the cord itself.
Symptoms and signs are generally the same as one might see in extrinsic compression, but a suspended and dissociated sensory loss can only occur with intrinsic disease such as syringomyelia.
Urinary symptoms usually occur earlier in the course of an intrinsic cord disorder than with compressive disorders.
How should intrinsic cord diseases be investigated?
Imaging to exclude compressive lesion is the most important - i.e. MRI. Non specific signal change can be seen in spinal cord inflammation or infective conditions and others such as B12 deficiency.
Chest X ray, MRI spine, CSF examination, HTLV-1, HIV, syphilis serology and B12 are important acute investigations.
What is syringomyelia?
This is an expanding fluid filled cavity within the centre of the spinal cord (syrinx).
Presents with gradual onset over months or years with pain in cervical segments.
Anterior horn cell loss causes LMN signs at the level of the lesion.
Disruption of corticospinal tract causes UMN signs below it.
Suspended spinothalamic sensory loss at the level of the lesion, with preserved dorsal columns.
Occurs in a cape like distribution.
Associated with Arnold-Chiari malformations.
If extends into the brainstem it is syringobulbia
How does an anterior spinal artery infarct present?
Abrupt onset of anterior horn cell loss (LMN) at the level of the lesion, UMN features below it.
Dorsal columns are spared but spinothalamic loss causes bilateral diminished fine touch and pin prick sensation.
What is the Brown-Sequard syndrome?
Hemisection of the cord, most commonly seen in transverse myelitis or multiple sclerosis but can occur in trauma.
It presents with ipsilateral UMN signs and ipsilateral dorsal column loss with contralateral spinothalamic tract signs.
What are the features of subacute combined degeneration of the cord?
Caused by vitamin B12 deficiency.
Progressive spastic paraparesis with proprioception loss, absent reflexes due to peripheral neuropathy +/- optic nerve and cerebral involvement (dementia)
How does hereditary spastic paraparesis present?
Onset usually in adult life.
AD inheritance.
Slowly progressive UMN features affecting legs >arms.
Little if any sensory loss.
What is transverse myelitis?
Inflammation/ infection of a segment of the cord.
Usually caused by viruses (HZV), schistosomiasis, HIV, MS or sarcoidosis.
Presents with weakness and sensory loss often with pain developing over hours to days. UMN features below lesion.
Impaired sphincter function.
