26th June 2023

Brown-Séquard Syndrome

Distribution of motor and sensory loss in right hemisection of the lower thoracic spinal cord.

Image Source: Dr D Chang – own work

Brown-Séquard syndrome describes a pattern of sensorimotor loss resulting from damage to one half of the spinal cord (i.e. hemisection of the cord) causing:

• Ipsilateral loss of vibration sense and proprioception, with hemiparesis.
• Contralateral loss of pain and temperature sense, with a clinical sensory level usually 1 to 2 levels below the actual lesion.
• Ipsilateral loss of all sensory modalities at the level of the lesion, with radicular pain.
• Ipsilateral flaccid paralysis at the level of the lesion.

Brown-Séquard syndrome is usually caused by a traumatic spinal injury or intramedullary tumours confined to one side of the spinal cord, but an important cause of Brown-Séquard syndrome is transverse myelitis (see below).

This syndrome has the most favourable prognosis among the incomplete spinal cord syndromes, with 75% of patients able to ambulate independently at discharge from rehabilitation (75%) and nearly 70% perform functional skills and activities of daily living independently and favourable bladder and bowel function profile with continent bladder and bowel function achieved in 89% and 82%, respectively.