Osong Public Health Res Perspect.  2017 Aug;8(4):255-259. 10.24171/j.phrp.2017.8.4.04.

Correlation between Scapular Asymmetry and Differences in Left and Right Side Activity of Muscles Adjacent to the Scapula

• Kim SG

• KMID: 2394482
• DOI: http://doi.org/10.24171/j.phrp.2017.8.4.04

Abstract

OBJECTIVES
The aim of this study was to analyze the correlation between scapular asymmetry in young female adults and differences in left and right side activity of muscles adjacent to the scapula.
METHODS
This study included 60 female students from U university in Korea. In order to examine scapular asymmetry, the lateral scapular slide test (LSST) was used. The LSST was performed in 3 different postures (LSST-1, LSST-2, and LSST-3; i.e., 0°, 45°, and 90° of upper limb abduction, respectively). Muscle activity was measured during external and internal rotation of the shoulder joints. Muscle activity was measured at the upper, middle, and lower trapezius, and the serratus anterior.
RESULTS
In external shoulder rotation, there was a significant correlation (R = 0.450) between LSST-2 and the middle trapezius. In internal shoulder rotation, there was a significant correlation (R = 0.472) between LSST-2 and the upper trapezius, and between LSST-3 and the lower trapezius (R = 0.657); these results demonstrated a moderate positive linear correlation.
CONCLUSION
There was a positive correlation between left and right scapular asymmetry and the difference in left and right muscle activity of the trapezius in female adults. Problems in the trapezius may lead to scapular asymmetry.

Keyword

scapula; shoulder joint; anthropometry; electromyography

MeSH Terms

Adult
Anthropometry
Electromyography
Female
Humans
Korea
Muscles*
Posture
Scapula*
Shoulder
Shoulder Joint
Superficial Back Muscles
Upper Extremity