Reliability of Biomechanical Spasticity Measurements at the Elbow of People Poststroke  Andrew J. Starsky, MPT, Samir G. Sangani, BS, John R. McGuire, MD, Brent Logan, PhD, Brian D. Schmit, PhD  Archives of Physical Medicine and Rehabilitation  Volume 86, Issue 8, Pages 1648-1654 (August 2005) DOI: 10.1016/j.apmr.2005.03.015 Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 1 The load cell and manipulandum used in our study. Archives of Physical Medicine and Rehabilitation 2005 86, 1648-1654DOI: (10.1016/j.apmr.2005.03.015) Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 2 (A) The parameter of peak torque was obtained by examining the maximum torque value. (B) Peak stiffness and onset angle were identified from the stiffness curve. Archives of Physical Medicine and Rehabilitation 2005 86, 1648-1654DOI: (10.1016/j.apmr.2005.03.015) Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 3 Representative data during passive elbow extension on a stroke patient. These data were collected from a single subject at 90°/s. The top trace represents elbow angle moving into extension, holding for 5 seconds, and then moving back into flexion. The second trace represents the raw elbow torque, with a downward deflection denoting a flexion torque and an upward deflection denoting an extension torque. The third trace represents the raw electromyographic signal from the biceps of the stretched arm. The fourth trace represents the raw electromyographic signal from the triceps of the stretched arm. As the arm was extended, the biceps activated via the stretch reflex and generated flexion torque, which diminished as the stretch was held. As the elbow was flexed, the triceps activated, eliciting extension torque at the elbow. Archives of Physical Medicine and Rehabilitation 2005 86, 1648-1654DOI: (10.1016/j.apmr.2005.03.015) Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 4 Variation of the reflex torque with passive elbow extension speed on a single stroke subject. The reflex torque increased as the speed of the perturbation increased. Archives of Physical Medicine and Rehabilitation 2005 86, 1648-1654DOI: (10.1016/j.apmr.2005.03.015) Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 5 Comparison of test parameters among all subjects on the different testing dates. (A) The average peak torque when the elbow was extended at 90°/s. Variation among the subjects and variation among the different test dates was evident. (B) Comparison of peak stiffness values. (C) Comparison of onset angles. Archives of Physical Medicine and Rehabilitation 2005 86, 1648-1654DOI: (10.1016/j.apmr.2005.03.015) Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 6 Biomechanic parameters compared with the Ashworth Scale. The Spearman rank correlation coefficients for the biomechanic parameters are compared with the coefficients for the Ashworth scores at the elbow. Abbreviations: 30 Torque, the peak torque at 30°/s; 60 Torque, the peak torque at 60°/s; 90 Torque, the peak torque at 90°/s; 30 Stiffness, the peak stiffness at 30°/s; 60 Stiffness, the peak stiffness at 60°/s; 90 Stiffness, the peak stiffness at 90°/s; 30 Angle, onset angle at 30°/s; 60 Angle, onset angle at 60°/s; 90 Angle, onset angle at 90°/s. Archives of Physical Medicine and Rehabilitation 2005 86, 1648-1654DOI: (10.1016/j.apmr.2005.03.015) Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 7 Comparison of the reliability values obtained with the different testing protocols for each parameter. Reliability greater than 80% for each parameter was observed with 2 days of testing. Archives of Physical Medicine and Rehabilitation 2005 86, 1648-1654DOI: (10.1016/j.apmr.2005.03.015) Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions