Table 2.

The American Spinal Injury Association Impairment Scale (AIS). AIS grades from A to E considering the completeness of paralysis and the motor and sensory function test [36].

AIS Grade	A	B	C	D	E
Clinical State	Complete no motor or sensory function is preserved in the sacral segments S4–S5	Incomplete sensory but not motor function is preserved below the NLI and includes the sacral segments S4–S5	Incomplete motor function is preserved below the NLI, and more than half of key muscles below the NLI have a muscle grade less than 3	Incomplete motor function is preserved below the NLI, and at least half of key muscles below the NLI have a muscle grade of 3 or more	Normal motor and sensory function is normal