A Cadaveric Study of Strain on the Subscapularis Muscle Takayuki Muraki, PT, PhD, Mitsuhiro Aoki, MD, PhD, Eiichi Uchiyama, MD, PhD, Hiroshi Takasaki, PT, MS, Gen Murakami, MD, PhD, Shigenori Miyamoto, PT, PhD  Archives of Physical Medicine and Rehabilitation  Volume 88, Issue 7, Pages 941-946 (July 2007) DOI: 10.1016/j.apmr.2007.04.003 Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 1 Schematic representation of the experimental setup. A shoulder specimen was mounted vertically on a wood jig. Precise displacement sensors (Pulse-Coderb) were attached to the upper, middle, and lower fiber groups of the subscapularis muscle. 3SPACE sensorsc were attached to the acromion and humerus. Archives of Physical Medicine and Rehabilitation 2007 88, 941-946DOI: (10.1016/j.apmr.2007.04.003) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 2 Photograph and diagram of the Pulse Coder. (A) The Pulse-Coder, which was aligned with the muscle fibers, was used to measure the strain on the muscles by determining the changes in the length between specified points. (B) The 4 fishhook-like barbed points, which were inserted in the middle of the muscle, prevented the sensor from slipping out of the muscle. Archives of Physical Medicine and Rehabilitation 2007 88, 941-946DOI: (10.1016/j.apmr.2007.04.003) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 3 The arm elevation positions used in this measurement: (A) scapular plane and (B) axial plane. In the globe graph, longitudinal lines represent the angle of the elevation plane and latitudinal lines represent the elevation angles. Archives of Physical Medicine and Rehabilitation 2007 88, 941-946DOI: (10.1016/j.apmr.2007.04.003) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 4 Strain on the following upper fiber groups of the subscapularis muscle at each glenohumeral joint position. Values are mean ± SD. Abbreviations: Abd, abduction; Elev, elevation; ER, external rotation; Flex, flexion; H. Abd, horizontal abduction; IR, internal rotation. Archives of Physical Medicine and Rehabilitation 2007 88, 941-946DOI: (10.1016/j.apmr.2007.04.003) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 5 Strain on the following middle fiber groups of the subscapularis muscle at each glenohumeral joint position. Values are mean ± SD. Abbreviations: see fig 4. Archives of Physical Medicine and Rehabilitation 2007 88, 941-946DOI: (10.1016/j.apmr.2007.04.003) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

Fig 6 Strain on the following lower fiber groups of the subscapularis muscle at each glenohumeral joint position. Values are mean ± SD. *Position showed a significantly greater strain than the neutral position (P<.05). Abbreviations: see fig 4. Archives of Physical Medicine and Rehabilitation 2007 88, 941-946DOI: (10.1016/j.apmr.2007.04.003) Copyright © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions