Spinal cord injury (SCI) involves an insult to the spinal cord with resultant disturbance in motor, sensory or autonomic function which may be temporary or permanent.
Important definitions
Paresis: partial loss of power; weakness.
Plegia: total loss of power; paralysis.
Myelopathy: caused by damage to the spinal cord, which ends at L1.
Radiculopathy: damage/compression to nerve roots with symptoms in the distribution of the root.
Tetraplegia or quadriplegia: injury involving all four limbs.
Monoplegia: of one limb.
Paraplegia: bilateral lower-limb involvement.
Neurogenic shock: triad of hypotension, hypothermia and bradycardia due to interruption of sympathetic nervous system input (T1 – L3) with unopposed vagal input. Note: hypovolaemic shock causes tachycardia.
Spinal shock: a transient physiological reflex with depression of spinal cord function associated with loss of all motor and sensory function, including reflexes and anal tone, below the level of injury. Catecholamine release will lead to a transient hypertension, followed by hypotension and accompanied by flaccid paralysis, double incontinence and priapism. Duration may be hours to days until function returns to the reflex arcs below the injury level.
Classification
ASIA (American Spinal Injury Association) impairment scale: A (complete motor and sensory loss including S4–5); B (incomplete: sensory but no motor function preserved below injury); C (incomplete: motor function preserved below injury with power < 3); D (incomplete: motor function preserved below injury with power ≥ 3); E (normal). An incomplete lesion may progress to a complete lesion and vice versa.