The Effect of Poststroke Impairments on Brachialis Muscle Architecture as Measured by Ultrasound  Le Li, MSc, Kai Y. Tong, PhD, Xiaoling Hu, PhD  Archives of Physical Medicine and Rehabilitation  Volume 88, Issue 2, Pages 243-250 (February 2007) DOI: 10.1016/j.apmr.2006.11.013 Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 1 Typical ultrasonography imaging of the brachialis (BRA) muscle. (A) Original image and (B) image with labels. The bright fringe in the lower region of the image shows the muscle–bone boundary (BRA–humerus). The upper shaded area is the biceps brachii (BIC), the lower shaded area is the humerus and the BRA is between these 2 regions. Aponeurosis (APO) is the boundary between the BRA and BIC. Lm is the visualized part of the entire muscle fascicle length and can be measured directly; MT1 and MT2 are the distance of the fiber distal end point to the superficial aponeurosis and the distance of the fiber proximal end to the bone, respectively; α is the pennation angle. Archives of Physical Medicine and Rehabilitation 2007 88, 243-250DOI: (10.1016/j.apmr.2006.11.013) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 2 Brachialis (A) pennation angle and (B) fascicle length in the affected side and the unaffected side of the subjects after stroke (affected group and unaffected group, respectively) as a function of elbow joint angle at the rest condition (mean, n=7). The error bar represents 1 standard deviation (SD). *Any significant difference between the affected group and the unaffected group (t test, P<.05). Archives of Physical Medicine and Rehabilitation 2007 88, 243-250DOI: (10.1016/j.apmr.2006.11.013) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 3 Brachialis (A) fascicle length and (B) pennation angle changes according to the contraction level in the affected group and the unaffected group at a fixed position of elbow flexion at 90° (mean, n=7). The error bar represents 1 SD. *Any significant difference between the affected group and the unaffected group (t test, P<.05). Archives of Physical Medicine and Rehabilitation 2007 88, 243-250DOI: (10.1016/j.apmr.2006.11.013) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions