title: Effect of scapular stabilization during cross-body stretch on the hardness of infraspinatus, teres minor, and deltoid muscles: An ultrasonic shear wave elastography study.
abstract: Posterior shoulder tightness is a contributing factor to shoulder injuries. Cross-body stretch is a method frequently prescribed to stretch the posterior shoulder structures. This stretching is performed horizontally adducting the shoulder with or without manual stabilization of the scapula by the therapist. However, no studies have investigated the effect of scapular stabilization during cross-body stretch using shear elastic modulus as an index of muscle hardness in vivo.
  
  
  
  The aim of this study was to quantitatively examine, using ultrasonic shear wave elastography, whether scapular stabilization during cross-body stretch effectively decreased the hardness of the infraspinatus, the teres minor, or the posterior portion of the deltoid muscles.
  
  
  
  A randomized, repeated-measures, cross-over design.
  
  
  
  Twenty healthy men participated in this study. The shear elastic modulus of the teres minor, the superior and inferior portions of the infraspinatus, and the posterior portion of the deltoid were measured before, and immediately after cross-body stretch with and without scapular stabilization.
  
  
  
  The shear elastic modulus of the superior and inferior portions of the infraspinatus decreased significantly after cross-body stretch with scapular stabilization, but there was no significant change in the shear modulus of the measured muscles after cross-body stretch without scapular stabilization.
  
  
  
  Our results suggest that manual scapular stabilization during cross-body stretch effectively decreases the hardness of the infraspinatus muscle.
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan. Electronic address: umehara.jun.77z@st.kyoto-u.ac.jp.
authors.forename: Jun
authors.initials: J
authors.lastname: Umehara
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hasegawa
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan; Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Nishishita
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Umegaki
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Tanaka
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Fujita
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Kusano
authors.affiliation: Human Health Science, Graduate School of Medicine, Kyoto University, 53 Shogoin-Kawahawa-cho, Kyoto, 606-8507, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Ichihashi
mesh_terms: D000328:Adult; D057645:Deltoid Muscle / Q000000981:diagnostic imaging / Q000502:physiology*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques; D006801:Humans; D008297:Male; D052580:Muscle Stretching Exercises; D016059:Range of Motion, Articular / Q000502:physiology; D017006:Rotator Cuff / Q000502:physiology*; D012540:Scapula / Q000502:physiology*; D014463:Ultrasonography; D055815:Young Adult
keywords: Cross-body stretch; Scapular stabilization; Shear wave elastography