Search

BIO DESIGN

pISSN 1225-8962
eISSN 2287-982X

Article

Article

Original Article

Split Viewer

Phys. Ther. Korea 2023; 30(3): 245-252

Published online August 20, 2023

https://doi.org/10.12674/ptk.2023.30.3.245

© Korean Research Society of Physical Therapy

The Relationship Between Upper Extremity, Trunk and Hip Muscle Strength and the Modified Upper Quarter Y-balance Test

Joo-young Jeon1 , PT, BPT, Jun-hee Kim2 , PT, PhD, Oh-yun Kwon2,3 , PT, PhD

1Department of Physical Therapy, The Graduate School, Yonsei University, 2Kinetic Ergocise Based on Movement Analysis Laboratory, 3Department of Physical Therapy, College of Software and Digital Healthcare Convergence, Yonsei University, Wonju, Korea

Correspondence to: Oh-yun Kwon
E-mail: kwonoy@yonsei.ac.kr
https://orcid.org/0000-0002-9699-768X

Received: July 31, 2023; Revised: August 5, 2023; Accepted: August 7, 2023

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background: Various functional tests such as upper quarter Y-balance test (UQYBT) are used to evaluate shoulder stability and mobility in clinical or sports fields. Previous studies have been conducted to determine the correlation between the scapular or trunk muscle and UQYBT. However, the correlation between UQYBT and hip flexor, which can be considered as a core muscle, has not been confirmed. Objects: To verify the relationship between the UQYBT and scapular muscle (scapular protractor and lower trapezius [LT]), trunk muscle, and hip flexor strengths in healthy male participants.
Methods: A total of 37 healthy male participants were recruited and underwent UQYBT in the push-up posture. The isometric strength of the scapular protractor, LT, trunk flexor and extensor, and hip flexors were measured using a smart KEMA strength sensor (KOREATECH Inc.).
Results: The superolateral direction of the UQYBT was moderately to strongly related to trunk extensor (r = 0.443, p < 0.01), scapular protractor (r = 0.412, p < 0.05), LT (r = 0.436, p < 0.01), and both sides of the hip flexors (supporting-side: r = 0.669, p < 0.01; non-supporting- side: r = 0.641, p < 0.01). The inferolateral direction of the UQYBT was moderately related to the scapular protractor (r = 0.429, p < 0.01), LT (r = 0.511, p < 0.01), and both sides of hip flexors (supporting-side: r = 0.481, p < 0.01; non-supporting-side: r = 0.521, p < 0.01). The medial direction of the UQYBT was moderately to strongly related with the scapular protractor (r = 0.522, p < 0.01), LT (r = 0.541, p < 0.01), and both sides of hip flexors (supporting-side: r = 0.605, p < 0.01; non-supporting-side: r = 0.561, p < 0.01).
Conclusion: This study showed that the strength of the scapular muscles, trunk muscles, and hip flexor muscles correlated to the UQYBT. Therefore, the strength of not only the scapular and trunk muscles but also the hip flexor muscles should be considered to improve the UQYBT.

Keywords: Muscle strength, Physical examination, Psoas muscle

Article

Original Article

Phys. Ther. Korea 2023; 30(3): 245-252

Published online August 20, 2023 https://doi.org/10.12674/ptk.2023.30.3.245

Copyright © Korean Research Society of Physical Therapy.

The Relationship Between Upper Extremity, Trunk and Hip Muscle Strength and the Modified Upper Quarter Y-balance Test

Joo-young Jeon1 , PT, BPT, Jun-hee Kim2 , PT, PhD, Oh-yun Kwon2,3 , PT, PhD

1Department of Physical Therapy, The Graduate School, Yonsei University, 2Kinetic Ergocise Based on Movement Analysis Laboratory, 3Department of Physical Therapy, College of Software and Digital Healthcare Convergence, Yonsei University, Wonju, Korea

Correspondence to:Oh-yun Kwon
E-mail: kwonoy@yonsei.ac.kr
https://orcid.org/0000-0002-9699-768X

Received: July 31, 2023; Revised: August 5, 2023; Accepted: August 7, 2023

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background: Various functional tests such as upper quarter Y-balance test (UQYBT) are used to evaluate shoulder stability and mobility in clinical or sports fields. Previous studies have been conducted to determine the correlation between the scapular or trunk muscle and UQYBT. However, the correlation between UQYBT and hip flexor, which can be considered as a core muscle, has not been confirmed. Objects: To verify the relationship between the UQYBT and scapular muscle (scapular protractor and lower trapezius [LT]), trunk muscle, and hip flexor strengths in healthy male participants.
Methods: A total of 37 healthy male participants were recruited and underwent UQYBT in the push-up posture. The isometric strength of the scapular protractor, LT, trunk flexor and extensor, and hip flexors were measured using a smart KEMA strength sensor (KOREATECH Inc.).
Results: The superolateral direction of the UQYBT was moderately to strongly related to trunk extensor (r = 0.443, p < 0.01), scapular protractor (r = 0.412, p < 0.05), LT (r = 0.436, p < 0.01), and both sides of the hip flexors (supporting-side: r = 0.669, p < 0.01; non-supporting- side: r = 0.641, p < 0.01). The inferolateral direction of the UQYBT was moderately related to the scapular protractor (r = 0.429, p < 0.01), LT (r = 0.511, p < 0.01), and both sides of hip flexors (supporting-side: r = 0.481, p < 0.01; non-supporting-side: r = 0.521, p < 0.01). The medial direction of the UQYBT was moderately to strongly related with the scapular protractor (r = 0.522, p < 0.01), LT (r = 0.541, p < 0.01), and both sides of hip flexors (supporting-side: r = 0.605, p < 0.01; non-supporting-side: r = 0.561, p < 0.01).
Conclusion: This study showed that the strength of the scapular muscles, trunk muscles, and hip flexor muscles correlated to the UQYBT. Therefore, the strength of not only the scapular and trunk muscles but also the hip flexor muscles should be considered to improve the UQYBT.

Keywords: Muscle strength, Physical examination, Psoas muscle

Fig 1.

Figure 1.Measurement of isometric muscle strength. (A) Scapular protractor, (B) lower trapezius, (C) hip flexor, (D) trunk flexor, and (E) trunk extensor.
Physical Therapy Korea 2023; 30: 245-252https://doi.org/10.12674/ptk.2023.30.3.245

Fig 2.

Figure 2.Upper quarter Y-balance test (UQYBT). (A) Modified UQYBT start position. (B) Modified UQYBT end position (each direction of medial, superolateral, and inferolateral).
Physical Therapy Korea 2023; 30: 245-252https://doi.org/10.12674/ptk.2023.30.3.245

Table 1 . Participants’ characteristics.

VariableMale (N = 37)
Age (y)27.54 ± 6.20
Height (cm)174.76 ± 6.45
Weight (kg)76.89 ± 12.36

Values are presented as mean ± standard deviation..


Table 2 . Isometric muscle strength and each direction score and a composite score of UQYBT.

VariableMale (N = 37)
Muscle strength (%bw)
Supporting-side scapular protractor21.04 ± 8.72
Supporting-side lower trapezius8.97 ± 3.66
Supporting-side hip flexor19.78 ± 6.91
Non-supporting-side hip flexor18.19 ± 6.83
Trunk flexor16.75 ± 6.43
Trunk extensor33.65 ± 11.69
UQYBT score (%AL)
Medial108.00 ± 9.80
Superolateral58.94 ± 13.17
Inferolateral70.38 ± 12.69
Composite score79.26 ± 9.97

Values are presented as mean ± standard deviation. UQYBT, upper quarter Y-balance test; bw, body weight; AL, arm length..


Table 3 . Correlation between isometric strength and upper quarter Y-balance test.

Supporting-side scapular protractorSupporting-side lower trapeziusNon-supporting-side hip flexorSupporting-side hip flexorTrunk flexorTrunk extensor
Medial direction0.522**0.541**0.561**0.605**0.2320.261
Superolateral direction0.412*0.436**0.641**0.669**0.379*0.443**
Inferolateral direction0.429**0.511**0.521**0.481**0.1710.250
Composite score0.521**0.567**0.664**0.678**0.3020.368*

Values are presented as r value. *p < 0.05, **p < 0.01..