Spinal Cord Assessment Tool for Spastic Reflexes (SCATS)

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Tool Description

  • Physiologically based measure for spastic reflexes for use in individuals with SCI.
  • Developed in response to the demand for a standardized, simple clinical measure that encompasses the primary spastic reaction in the SCI population.
  • The SCATS is split into 3 subscales, each addressing a separate spasm:
    1) Clonus
    2) Flexor spasms
    3) Extensor spasms.
    For each subscale, the spasm is triggered and then rated with a score ranging from 0 – 3.

ICF Domain:

Body Function – Subcategory: Neuromusculoskeletal & Movement-related Functions and Structures.

Number of Items:


Brief Instructions for Administration & Scoring


  • Clinician-administered.
  • SCATS clonus is measured by rapid passive dorsiflexion.  The degree of spasm is rated between 0 (no spasm) – 3 (severe spasm lasting longer than 10 seconds).
  • SCATS flexor spasm is measured by applying a pinprick stimulus to the medial arch with the knee and hip extended straight. The degree of spasm is rated between 0 (no spasm) and 3 (severe spasm, 30 knee and hip flexion).
  • SCATS extensor spasm is measured by extending the hip and knee joints from with the knee and hip extended at 90 and 110 degrees. The degree of spasm is rated between 0 (no spasm) and 3 (severe spasm, longer than 10 seconds).


  • Equipment to quantitatively measure joint angle changes.

Scoring: N/A


MCID: not established in SCI
SEM: not established in SCI
MDC: not established in SCI

  • Scores in each subscale range from 0 - 3, with scores above zero indicating the presence of spasm.
  • Scores of three indicate severe spasms.
  • The results of the SCATS will indicate to the clinician the type(s) of spasticity present in an individual, as well as the degree of severity of each type of spasticity.
  • No normative data for the SCI population has been reported.



Training Required:

Administration should be done by a trained clinician.


See the how-to page of this tool.

Clinical Considerations

  • The SCATS does not gather information on patient perspective, an important aspect of spasms, as some spasms are perceived as beneficial to the patient.
  • Each subscale is quick (<5 sec) to administer; however, if a spasm is elicited, spasm duration is patient specific and could be enduring.
  • The SCATS appears to be comprehensive in differentiating three different spastic responses.
  • As spasms are often uncomfortable for individuals with SCI, and the SCATS is recommended to be done in tandem with self reporting measures of spasm, there is the possibility of high respondent burden in terms of both length and comfort.  The measure could be conducted during a home visit or at a clinic/hospital.

Measurement Property Summary

# of studies reporting psychometric properties: 1


  • High Test-Retest kappa coefficient: κ = 0.614 ± 0.08 – 1.000 ± 0.08
  • High Inter-rater kappa coefficient: κ = 0.669 ± 1.000 (P < .01)

(Akpinar et al. 2016; N=47, mean age (range): 44.19 (18-88), mean no. months post-injury (range): 43.96 (6-197))


  • High correlation range with kinematic and electromyography:
    r = 0.69-0.94 (P < .01)

  • High correlation of SCATS extensor scores with Ashworth hip flexors:
    r = 0.98

  • High correlation of SCATS extensor scores with Ashworth knee flexors:
    r = 0.88

  • High correlation of SCATS extensor scores with Ashworth ankle plantar flexors:
    r = 0.61

(Benz et al. 2005; N=11, age range: 16-65)

  • High correlation of SCATS clonus scores with Modified Ashworth Scale (MAS) scores of hip extensor muscles, knee flexor muscles, and plantar flexor muscles:
    P < .01

  • High correlation of SCATS flexor spasm scores with MAS score of ankle plantar flexor muscles:
    P < .05

(Akpinar et al. 2016; N=47, mean age (range): 44.19 (18-88), mean no. months post-injury (range): 43.96 (6-197))


No values were reported for the responsiveness of the SCATS for the SCI population.

Floor/ceiling effect:

No values were reported for the presence of floor/ceiling effects in the SCATS for the SCI population.


Dr. Vanessa Noonan, Matthew Querée, Gita Manhas

Date Last Updated:

July 22, 2020

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Download Worksheet:

Worksheet Document
SCATS - clonus:

Clonus of the plantarflexors was quantified in response to a rapid passive dorsiflexion of the ankle (A). The ankle was dorsiflexed at an angle that triggered clonus, and the duration of clonic bursts was timed. An ordinal rating from 0 to 3 was determined by the duration of clonic activity where 0 is no reaction; 1 is mild, clonus was maintained less than 3 seconds; 2 is moderate, clonus persisted between 3 and 10 seconds; and 3 is severe, clonus persisted for more than 10 seconds.

SCATS - flexor spasms:

With the knee and hip extended to 0°, the clinician applied a pinprick stimulus for 1 second to the medial arch of the subject’s foot (B). Excursion of the big toe into extension, ankle dorsiflexion, and knee and hip flexion were visually observed for severity. The rating scale consisted of a score from 0 to 3, where 0 is no reaction to stimulus; 1 is mild, less than 10° of excursion in flexion at the knee and hip or extension of the great toe; 2 is moderate, 10° to 30° of flexion at the knee nd hip; and 3 is severe, 30° or greater of knee and hip flexion.

SCATS - extensor spasms:

With the contralateral limb extended, the tested knee and hip were positioned at angle of 90° to 110° of hip and knee flexion, and then both joints were simultaneously extended. One hand cupped the heel while the other was placed on the outside of the thigh (C). Once a reaction was elicited, the duration of visible muscle contraction in the quadriceps muscle was measured by observing superior displacement of the patella. The timed scale (0–3) that was used for clonus was also applied to the timed extensor spasms.





Equipment Needed


Adams M, Martin Ginis K, Hicks A. The Spinal Cord Injury Spasticity Evaluation Tool: Development and Evaluation. Arch Phys Med Rehabil. 2007;88:1185-1192.

Benz EN, Hornby TG, Bode RK, Scheidt RA, Schmit BD. A physiologically based clinical measure for spastic reflexes in spinal cord injury. Arch Phys Med Rehabil 2005;86:52-59.

Little JW, Micklesen P, Umlauf R, Britell C. Lower extremity manifestations of spasticity in chronic spinal cord injury. Am J Phys Med Rehabil. 1989;68:32-36