Weakness Is the Primary Contributor to Finger Impairment in Chronic Stroke  Derek G. Kamper, PhD, Heidi C. Fischer, MS, OTR/L, Erik G. Cruz, William Z. Rymer, MD, PhD  Archives of Physical Medicine and Rehabilitation  Volume 87, Issue 9, Pages 1262-1269 (September 2006) DOI: 10.1016/j.apmr.2006.05.013 Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 1 The difference in the reflex torque response to stretch between the 2 hands for the severely impaired and moderately impaired subjects. Error bars represent 1 SD. The response was larger for the severely impaired subjects (P<.01). Archives of Physical Medicine and Rehabilitation 2006 87, 1262-1269DOI: (10.1016/j.apmr.2006.05.013) Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 2 The ratio of normalized finger flexor to finger extensor electromyographic (EMG) activity during voluntary isometric extension for the impaired and unimpaired hands. Archives of Physical Medicine and Rehabilitation 2006 87, 1262-1269DOI: (10.1016/j.apmr.2006.05.013) Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 3 The difference in the amount of extensor activity during voluntary extension and voluntary flexion for the severely impaired and moderately impaired subjects. Error bars represent 1 SD. Archives of Physical Medicine and Rehabilitation 2006 87, 1262-1269DOI: (10.1016/j.apmr.2006.05.013) Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 4 Example of the static stiffness (offset torque) measured at different joint angles for the impaired and unimpaired hands of 1 stroke survivor. Positive angle denotes MCP extension, while positive static torque denotes a flexion torque. A second-order polynomial was fit to each dataset. Archives of Physical Medicine and Rehabilitation 2006 87, 1262-1269DOI: (10.1016/j.apmr.2006.05.013) Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 5 Example of the dynamic stiffness measured at different joint angles for the impaired and unimpaired hands of 1 stroke survivor. Positive angle denotes MCP extension, whereas positive dynamic stiffness denotes a flexion torque. A second-order polynomial was fit to each dataset. Archives of Physical Medicine and Rehabilitation 2006 87, 1262-1269DOI: (10.1016/j.apmr.2006.05.013) Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 6 For the severely impaired group, the sum of the increased resistance to MCP extension after stroke because of positive symptoms, such as spasticity, increased static stiffness, and increased dynamic stiffness was still less than the deficit in isometric extension torque (right bar). Archives of Physical Medicine and Rehabilitation 2006 87, 1262-1269DOI: (10.1016/j.apmr.2006.05.013) Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions