International Standards for Neurological Classification of Spinal Cord Injury (ASIA Impairment Scale)

Last Updated

January 18, 2013

Purpose

The ASIA impairment scale (AIS) classifies motor and sensory impairment that results from a Spinal Cord Injury (SCI).

Link to Instrument

Instrument Details

Acronym AIS / ASIA

Area of Assessment

Functional Mobility
Strength
Upper Extremity Function

Assessment Type

Observer

Administration Mode

Paper & Pencil

Cost

Free

Diagnosis/Conditions

Spinal Cord Injury

Spinal Injuries

The ASIA Impairment Scale builds on the earlier Frankel scale but includes a number of significant improvements.
AIS A (complete) classification is defined by the absence of motor and sensory function in the sacral segments S4-S5. An AIS-A classification is made with a single observation.
The AIS B (sensory incomplete) classification is reserved for people with preserved sensation below the neurological level of injury and at sacral segments S4-S5; and no motor preserved more than 3 levels below the motor level on either side.
For AIS C and D (motor incomplete), the scale adds quantitative criteria for determining the appropriate diagnostic classification.
For AISC or D must have either: 1) voluntary anal sphincter contraction OR 2) sacral sensory sparing with motor sparing >3 levels below the motor level for that side of the body.
AIS C is assigned if half the key muscles below the neurological level of injuryare graded as less than 3/5.
AIS D is assigned if half or more of the key muscles below the neurological level of injury have a grade ≥ 3/5.
Unlike the A, B, C and D classifications, an AIS E classification implies the presence of a spinal cord injury but without detectable neurological deficits.
AIS classifications also differentiate incomplete SCI’s into one of 5 types:
1) A central cord syndrome diagnosis is associated with greater loss of upper versus lower limb function.
2) A hemi-section lesion of the spinal cord is classified as Brown-Sequard syndrome
3) An injury to the anterior spinal tracts is classified as Anterior cord syndrome
4) An injury to the conus is classified as conus medullaris syndrome
5) An injury to the spinal roots is classified as cauda equina syndrome

Number of Items

Varies

Tapered piece of cotton
Safety pin

10-60 minutes

Required Training

Reading an Article/Manual

Child

6 - 12

years

Adolescent

13 - 17

years

Adult

18 - 64

years

Elderly Adult

65 +

years

Instrument Reviewers

Initially reviewed by the Rehabilitation Measures Team; Updated by Cara Weisbach PT, DPT, Wendy Romney PT, DPT, NCS, and the SCI EDGE task force of the Neurology section of the APTA in 2012

Body Part

Upper Extremity
Lower Extremity

ICF Domain

Body Function

Measurement Domain

Motor
Sensory

Professional Association Recommendation

Recommendations for use of the instrument from the Neurology Section of the American Physical Therapy Association’s Multiple Sclerosis Taskforce (MSEDGE), Parkinson’s Taskforce (PD EDGE), Spinal Cord Injury Taskforce (PD EDGE), Stroke Taskforce (StrokEDGE), Traumatic Brain Injury Taskforce (TBI EDGE), and Vestibular Taskforce (Vestibular EDGE) are listed below. These recommendations were developed by a panel of research and clinical experts using a modified Delphi process.

For detailed information about how recommendations were made, please visit: http://www.neuropt.org/go/healthcare-professionals/neurology-section-outcome-measures-recommendations

*Abbreviations:*
HR	Highly Recommend
R	Recommend
*LS / UR*	Reasonable to use, but limited study in target group / Unable to Recommend
NR	Not Recommended

Recommendations for use based on acuity level of the patient:

Acute

(CVA < 2 months post)

(SCI < 1 month post)

(Vestibular < 6 weeks post)

Subacute

(CVA 2 to 6 months)

(SCI 3 to 6 months)

Chronic

(> 6 months)

SCI EDGE

Recommendations based on SCI AIS Classification:

	AIS A/B	AIS C/D
SCI EDGE	HR	HR

Recommendations for entry-level physical therapy education and use in research:

	Students should learn to administer this tool? (Y/N)	Students should be exposed to tool? (Y/N)	Appropriate for use in intervention research studies? (Y/N)	Is additional research warranted for this tool (Y/N)
SCI EDGE	Yes	Yes	Yes	Not reported

Considerations

Use of the AIS motor scale in a 2-dimensional model (separate UEMS and LEMS) increases the predictive power of the AIS motor scale.

Do you see an error or have a suggestion for this instrument summary? Please e-mail us!

Minimal Detectable Change (MDC)

Acute and Chronic SCI: (Marino 2008, n=16)

Smallest Real Difference
- Light tough = 4.1
- Pin-prick = 5.9
- UEMS = 2.0

Chronic SCI: (Clifton 1996, n=160, based on surgical or non-surgical group)

Minimal Detectable Change = .29
AIS motor score = 1 point
AIS pin-prick sensory = 7.8 points
AIS light-touch sensory = 12.95 points

Normative Data

AcuteTetraplegia : (Cifu et al, 1999; n = 375; sample analyzed into three age groups, 18 to 34, 35 to 64, & 65+ years, )

Outcome Measures for Each Injury Group:
	AIS Motor Admission	AIS Motor Discharge	FIM Motor Admission	FIM Motor Discharge
AIS A, B C2-C4	4.85	16.90	13.20	23.50
AIS A,B; C5-C8	14.62	24.33	16.53	33.58
AIS C; C2-C4	25.08	57.21	15.55	48.58
AIS C; C5-C8	34.31	59.93	20.89	57.75
AIS D; C2-C4	63.12	78.07	33.63	73.62
AIS D; C5-C8	65.32	78.63	35.53	72.43
ANOVA
f	125.61	70.37	30.87	67.42
p	.000	.000	.000	.000

Admission &Discharge Scores by Age Catagory:
Admission	18-34yrs	35-64yrs	65+yrs	p
AIS Motor	38.61	39.02	43.15	.239
FIM Motor	25.01	25.80	22.82	.201
FIM Cognitive	31.02	29.54	27.65	.001
Discharge	18-34yrs	35-64yrs	65+yrs	p
AIS Motor	57.67	57.52	56.56	.914
FIM Motor	62.38	56.37	49.74	.000
FIM Cognitive	33.86	32.54	29.86	.000

*showed greater differences in FIM scores from Admission to Discharge in younger>middle>older age groups

Test/Retest Reliability

Acute and Chronic SCI: (Curt & Dietz; 1997; n = 70 acute and 34 chronic SCI patients)

AIS Scores by Age and Diagnosis: () = ±
	Tetraplegia			Paraple gia
	Initial	6 months	% Change	Initial	6 months	% Change
N	31	31		39	39
Mean age	42.6 (22.3)			40.3 (17)
Male/Female	27/4			30/9
Complete / incomplete	12/19	11/20	8.3	17/22	14/25	17.6
AIS Motor	38.2 (30)	56.7 (31.7)	32.7*	60.2 (13.5)	68 (17.3)	11.5*
AIS light touch	65.2 (35)	70.6 (35.6)	7.7	86.1 (16.3)	88.7 (16.5)	2.9
AIS pin prick	54.5 (36.9)	63.2 (38.1)	13.7	82 (18)	86.5 (18.5)	5.2

Interrater/Intrarater Reliability

Chronic SCI : (Clifton et al, 1996; n = 19, intervention involved surgical intervention, at least 2 months apart)

Non-intervention (baseline to 1 year)
- Excellent intrarater reliability AIS Motor (ICC = 0.99)
- Excellent intrarater reliability AIS Pin prick (ICC = 0.84)
- Excellent intrarater reliability AIS Light touch (ICC = 0.80)
Intervention Group (2 months apart)
- Excellent intrarater reliability AIS Motor (ICC = 0.98)
- Excellent intrarater reliability AIS Pin prick (ICC = 0.83)
- Excellent intrarater reliability AIS Light touch (ICC 0.76)

Acute to Chronic SCI: (Savic et al. 2007; n=45, 3 months – 45 years post injury)

Interrater Reliability:

Excellent AIS total motor scores (ICC = 0.999)
Excellent AIS Pin prick (ICC = 0.997)
Excellent AIS Light touch (ICC = 0.988)
Adequate for motor scores for the 10 individual key muscles (weighted Kappa coefficient = 0.649–0.993, p>0.05)
Adequate for sensory and motor levels (unweighted Kappa coefficient = 0.68-0.78; p>0.01)

Chronic SCI : (Marino et al. 2008; n = 16, Tetraplegia n=10, (complete = 5; incomplete = 5) and paraplegia n=6, (complete = 5, incomplete = 1) rated by 16 raters (8 physicians and 8 physical therapists)

	All	Complete	Incomplete
AIS light touch	0.96ᵃ	0.99ᵃ	0.86ᵃ
AIS pin-prick	0.89ᵃ	0.99ᵃ	0.69ᵇ
AIS total motor	0.98ᵃ	1.00ᵃ	0.95ᵃ
UEMS (tetra)	0.96ᵃ	n/a	n/a
LEMS	n/a	n/a	0.98ᵃ
a- Excellent reliability(ICC ≥0.75) b- Adequate reliability(ICC 0.4<0.74)

Intra-rater Reliability:

Excellent AIS Light Tough ICC= 0.99
Excellent AIS Pin-Prick ICC = 0.99
Excellent AIS UEMS ICC = 0.98

Criterion Validity (Predictive/Concurrent)

Acute and Chronic SCI: (Curt et al, 1998, n=36 acute, n= 34 chronic)

Excellent predictive validity of AIS UEMS for hand function (in acute 0-110 days, r = 0.79, p<0.001; in chronic (> 6 months) r = 0.83 p<0.001)
Excellent predictive validity of AIS LEMS for ambulatory capacity (in acute r = 0.79, p<0.001; in chronic r = 0.78, p< 0.001)
Adequate predictive validity of sensory scores for ambulatory capacity in acute and chronic individuals, respectively for pin prick (r = 0.64 and 0.58, p = 0.001; and for light tough (r=0.55 and r = 0.63 p = 0.004).

Tetraplegia : (Cifu et al, 1999)

Young (m = 19.49) and middle (m = 21.66) aged patients tended to improve more between admission and discharge than older patients (m = 12.71)
Younger patients (m = 37.38) improved more than middle aged (30.57) and older (m = 26.92) patients

Acute & Chronic SCI : (Marino et al, 2004, n=4338, at discharge from inpatient rehabilitation from Model SCI centers ) –

Separate AIS upper and lower-extremity motor scores were found to be more predictive of subsequent FIM motor scores than using the total AIS motor score alone.

Construct Validity

Acute SCI : (van Hedel et al. 2009; n = 886 European participants; assessed at 2 weeks, 1, 3, 6 and 12 months post SCI; p<0.001)

		AIS C			AIS D
When assessed, mo	Test	Indoor Mobility	Moderate Distance	Outdoor Mobility	Indoor Mobility	Moderate Distance	Outdoor Mobility
< 1	10MWT	--	--	--	0.68	0.60	0.41
	WISCI II	--	--	--	0.74	0.65	0.42
1	10MWT	0.39	0.38	0.37	0.82^a	0.82^a	0.69
	WISCI II	0.44	0.44	0.49	0.82^a	0.80^a	0.68
3	10MWT	0.66	0.66	0.53	0.79^a	0.83^a	0.82^a
	WISCI II	0.66	0.65	0.51	0.85^a	0.81^a	0.79^a
6	10MWT	0.84^a	0.81^a	0.69	0.58	0.69	0.72
	WISCI II	0.75^a	0.73	0.62	0.74	0.75^a	0.72
12	10MWT	0.90^a	0.89^a	0.84^a	0.47	0.62	0.67
	WISCI II	0.91^a	0.89	0.81^a	0.75^a	0.80^a	0.76^a

10MWT = 10-m walking test

WISCI II = Walking Index for Spinal Cord Injury.

^a= Excellent Correlations ≥ 0.75

SCI: (Graves et al, 2006; n=6,116 from National Spinal Cord Injury Statistical Center Database)

Excellent construct validity of AIS total motor score and separate UEMS and LEMS to represent LE (r=.95-0.97)
Excellent construct validity of 2 separate scales UEMS and LEMS for UE key muscles (r= 0.76-0.97)
AIS Total motor score explained 13-73% of variance for UE key muscle (coefficients range from 0.36-0.86)
AIS motor scores using 2 separate scales UEMS and LEMS explained 58-94% of variance for UE key muscle (coefficients range from 0.76-0.97)
AIS total motor score and separate UEMS and LEMS represent LE ratings similarly, both with correlation coefficients ranging between 0.95-0.97
Overall AIS motor scale used as a single total score accounts for 82% of variance and use of AIS motor score as 2 separate scales accounts for 86% of variance.
Global Chi-square Fit = 2,596 with critical value of 6.635 indicating AIS better represents data with the use of 2 separate scales than with the total score

Face Validity

Not statistically assessed

Bibliography

Cifu, D. X., Seel, R. T., et al. (1999). "A multicenter investigation of age-related differences in lengths of stay, hospitalization charges, and outcomes for a matched tetraplegia sample." Archives of physical medicine and rehabilitation 80(7): 733-740. Find it on PubMed

Clifton, G. L., Donovan, W. H., et al. (1996). "Omental transposition in chronic spinal cord injury." Spinal Cord 34(8963963): 193-203. Find it on PubMed

Curt, A. and Dietz, V. (1997). "Ambulatory capacity in spinal cord injury: significance of somatosensory evoked potentials and ASIA protocol in predicting outcome." Arch Phys Med Rehabil 78(9014955): 39-43. Find it on PubMed

Furlan, J. C., Fehlings, M. G., et al. (2008). "Motor and sensory assessment of patients in clinical trials for pharmacological therapy of acute spinal cord injury: psychometric properties of the ASIA Standards." J Neurotrauma 25(11): 1273-1301. Find it on PubMed

Graves, D. E., Frankiewicz, R. G., et al. (2006). "Construct validity and dimensional structure of the ASIA motor scale." J Spinal Cord Med 29(1): 39-45. Find it on PubMed

Marino, R. J. and Graves, D. E. (2004). "Metric properties of the ASIA motor score: subscales improve correlation with functional activities." Arch Phys Med Rehabil 85(15520975): 1804-1810. Find it on PubMed

Marino, R. J., Jones, L., et al. (2008). "Reliability and repeatability of the motor and sensory examination of the international standards for neurological classification of spinal cord injury." J Spinal Cord Med 31(2): 166-170. Find it on PubMed

Savic, G., Bergstrom, E. M., et al. (2007). "Inter-rater reliability of motor and sensory examinations performed according to American Spinal Injury Association standards." Spinal Cord 45(6): 444-451. Find it on PubMed

van Hedel, H. J. and Dietz, V. (2009). "Walking during daily life can be validly and responsively assessed in subjects with a spinal cord injury." Neurorehabil Neural Repair 23(2): 117-124. Find it on PubMed

Last Updated

Purpose

Link to Instrument

Area of Assessment

Assessment Type

Administration Mode

Cost

Diagnosis/Conditions

Number of Items

Required Training

Instrument Reviewers

Body Part

ICF Domain

Measurement Domain

Professional Association Recommendation

Considerations

Minimal Detectable Change (MDC)

Normative Data

Test/Retest Reliability

Interrater/Intrarater Reliability

Criterion Validity (Predictive/Concurrent)

Construct Validity

Face Validity

Bibliography

Physical Activity Recall A...

Psychosocial Adjustment to...

6 Minute Push Test