Establishing Normative Data on Scapulothoracic Musculature Using Handheld Dynamometry

Armstrong Atlantic State University, USA.
Journal of sport rehabilitation (Impact Factor: 1.28). 11/2009; 18(4):502-20.
Source: PubMed


Scapular strength deficits have been linked to shoulder dysfunction.
To establish normative data on the scapulothoracic musculature in normal subjects using a handheld dynamometer.
Descriptive normative data study.
Field research.
172 subjects with varying levels of overhead activity.
A handheld dynamometer was used to test the upper, middle, and lower trapezius; rhomboids; and serratus anterior.
A 2-factor ANOVA was performed for each of the muscles by activity level and unilateral ratio by activity-level analyses. Post hoc analysis included multiple pairwise comparisons, using the Dunn-Bonferroni correction method.
Activity level did not significantly affect the unilateral ratios: Elevation:depression was 2.5:1, upward:downward rotation was 1.5:1, and protraction:retraction was 1.25:1. A rank order from strongest to weakest was established through significant comparisons.
The unilateral ratios along with the rank order should be considered when discussing scapular rehabilitation protocols.

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Available from: Bryan L Riemann, Oct 04, 2015
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    • "It is reasonable to assume that the dominant limb is more frequently used in daily activities compared to the non-dominant limb; therefore this data suggests there may be increased UT, SA, and MT strength in the dominant limb compared to the non-dominant limb. However, no studies have directly investigated the effects of arm dominance on scapular muscle strength or endurance in healthy individuals [12]. The purpose of this study was to investigate the effect of arm dominance on scapular muscle strength, measured with a HHD, and scapular muscle endurance in healthy individuals. "
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