Cord injury patterns

Anatomy

 

Spinal cord anatomy

 

Dorsal Columns 

- light touch, vibration & proprioception

- CTLS (cervical fibres central, sacral fibres lateral)

 

Lateral Corticospinal Tract

- motor tract

- CTLS (cervical central, sacral fibres peripheral)

 

Anterolateral Spinothalamic Tract

- pain & temperature

 

Incomplete Spinal Cord Injury Patterns

 

1.  Central Cord Syndrome

- most common

- poor prognosis

- hyperextension injury

- Upper limb > Lower limb (as above, cervical fibres are central)

- distal > proximal

- sacral sparing (typically)

- due to the arrangement of fibres in dorsal column and anterior corticospinal

 

Central cord

 

2.  Anterior Cord Syndrome

- complete paralysis with dorsal column sparing

- anterior spinothalamic & lateral corticospinal tracts lost

- secondary to ischaemic event secondary to the anterior spinal artery

 

Anterior cord syndrome

 

3.  Brown-Sequard syndrome

- cord hemisection

- usually secondary to laceration

- ipsilateral dorsal columns & motor

- contralateral loss pain & temperature

 

Brown Sequard

 

4.  Posterior Cord Syndrome

- rare

- dorsal column loss only

- due to tumour / iatrogenic injury

 

5.  Cauda equina syndrome

- injury below L1

- only nerve roots at this level

- lower motor nerve injury to lumbar and sacral nerve roots

- fecal incontinence + urinary incontinence

- nil anal tone or sensation

 

6.  Conus medullaris injury

- cord ends at L1

- injury at this level

- T12 / L1 burst fracture most common cause

- lower motor neuron lower limb weakness

- upper motor neuron sacral lesions

- may have a spastic bladder which enables urination without catheterisation

 

Sacral Sparing

 

Triad of

- anal voluntary contraction

- perianal sensation

- FHL function

 

Indicates

- incomplete injury

- potential for recovery

- due to pial arteries on cord surface supplying small amount of tissue 

 

Blood Supply

 

Blood supply spinal cord

 

Anterior Spinal Artery

- arises from vertebral arteries at foramen magnum

- supplies the entire cord except for dorsal columns

- narrows and may become absent in thoracic region

 

Posterior Spinal Arteries

- paired

- originate from vertebral arteries

- smaller

 

Segmental Arteries

- average of 8 paired arteries

- may be single segmental supply between T4 and T8

- Artery of Adamkiewicz from left between T9-11 in 80% cases