Assessment Overview

Purpose: The ASIA Impairment Scale was designed to classify motor and sensory impairments that result from spinal cord injuries. The scale includes testing light touch and pinprick over 28 sensory dermatomes. There are also 10 myotomes, 5 in the upper extremity and 5 in the lower extremity, that must be tested via manual muscle tests. Lastly, a rectal exam is conducted to check sensory and motor function in the S4 and S5 spinal segment.

Equipment: Piece of cotton, safety pin

ICF Category: Impairment, Body structure/function

Details: The ASIA Impairment Scale classifies spinal cord injuries (SCI) into five different categories, AIS A, B, C, D, and E. AIS A is a motor complete SCI where no motor or sensory function is preserved below the level of the lesion or in the sacral segments. AIS B is a sensory incomplete spinal cord injury where sensation, but not motor function is preserved below the level of the lesion. The sacral segments are also preserved. AIS C is a motor incomplete SCI where function is preserved in the sacral segments or the individual meets the criteria for a sensory incomplete SCI and has some motor function below the level of the lesion. AIS D is a motor incomplete SCI with at least half of the key muscles below the level of injury having a grade greater than or equal to a 3. AIS E means that there is normal sensation and motor function at every spinal segment, and the individual is neurologically intact. A complete injury is determined by the absence of a voluntary anal contraction, sensory scores of 0 in S4-S5, and no response to deep anal pressure. An incomplete injury means that there is partial sensation and/or motor function in levels below the neurologic level of the injury, including S4-S5. The neurologic level of the injury is the most caudal segment of the spinal cord with intact sensation and antigravity muscle function strength.

Assessment Handouts

Assessment Psychometrics

The ASIA Impairment Scale is classified as an impairment-based outcome measure. It is highly recommended (4/4) by Neuro PT EDGE for acute, subacute, and chronic SCI patients. It is highly recommended for all levels of SCI (AIS A-D), and students should learn to administer this test. The psychometrics for this outcome measure are presented in the list below.

• Construct Validity:

  • Significant correlation with 10 MWT in acute SCI for AIS C and D

  • Significant correlation with WISCI-II in acute SCI for AIS C and D

  • Excellent construct validity of two separate scales UEMS and LEMS for UE key muscles

• Floor/Ceiling Effects: ASIA UEMS: 42% at ceiling; ASIA LEMS: 53% at floor

• Interrater Reliability: Excellent for chronic SCI for:

  • Motor (ICC=0.99)

  • Pinprick (ICC=0.99)

  • Light touch (ICC=0.98)

• Intrarater Reliability: Excellent in chronic SCI for:

  • Motor (ICC=0.99)

  • Pinprick (ICC=0.84)

  • Light touch (ICC=0.80)

• MCID:

  • Sensory score=5.19

  • Motor score=4.48

  • Upper Extremity score=2.72

  • Lower Extremity score=3.66

• Mean Data: Variable, differs between AIS level, neurologic level of injury, and time since injury

• MDC:

  • Total motor score=1.87

  • Total sensory score=3.87

  • Light touch=4.1

  • Pinprick=5.9

  • UEMS=2.0