Posttraumatic Spinal Cord Injury without Radiographic Abnormality

Table 1

Summarized descriptions of ASIA Impairment Scale (AIS) Grades A, B, C, D, and E. Please note that only patients with an initial SCI and neurological findings receive an AIS grade. (Source: with permission from American Spinal Injury Association: International Standards for Neurological Classification of Spinal Cord Injury.)

American Spinal Injury Association (ASIA) Impairment Scale (AIS)
Grade	Description
A	Complete	No sensory or motor function is preserved in the sacral segments S4-5
B	Sensory incomplete	Sensory but not motor function is preserved below the neurological level and includes the sacral segments S4-5 AND no motor function is preserved more than three levels below the motor level on either side of the body
C	Motor incomplete	Motor function is preserved at the most caudal sacral segments for voluntary anal contraction OR the patient meets the criteria for sensory incomplete status
D	Motor incomplete	Motor incomplete status as defined above, with at least half (half or more) of key muscle functions below the single NLI having a muscle grade ≥ 3
E	Normal	If sensation and motor function are graded as normal in all segments and the patient had prior deficits, then the AIS grade is E