Hannah DC, Scibek JS, Carcia CR, Phelps AL. Junior and Collegiate Tennis Players Display Similar Bilateral Asymmetries of Humeral Retroversion.
J Athl Train 2021;
56:464022. [PMID:
33848357 PMCID:
PMC8675307 DOI:
10.4085/1062-6050-0686.20]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CONTEXT
Overhead throwing athletes consistently display significant bilateral differences in humeral retroversion (HRV). However, there is limited evidence regarding HRV asymmetries in tennis players despite similarities between the overhead throw and tennis serve.
OBJECTIVE
To determine if junior and collegiate tennis players demonstrate bilateral differences in HRV, and whether the magnitude of the side-to-side difference (HRVΔ) was similar across different age groups.
DESIGN
Cross-Sectional Study Setting: Field-Based Patients or Other Participants: Thirty-nine healthy tennis players were stratified into three age groups: Younger Juniors (n = 11; age = 14.5 ± 0.5 years), Older Juniors (n = 12; age = 17.1 ± 0.9 years), and Collegiate (n = 16; age = 19.6 ± 1.2 years).
MAIN OUTCOME MEASURES
Three-trial means were calculated for HRV for the dominant and nondominant limbs, and HRVΔ was calculated by subtracting the mean of the nondominant side from the dominant side. Paired-sample t-tests were utilized to determine bilateral differences in HRV, while a one-way ANOVA was used to compare HRVΔ between groups.
RESULTS
For all three groups, HRV was significantly greater in the dominant arm compared to the nondominant arm (Younger Juniors: dominant = 62.8° ± 9.1° vs nondominant = 56.3° ± 6.8°, P = .039; Older Juniors: dominant = 75.5° ± 11.2° vs nondominant = 68.6° ± 14.2°, P = .043; Collegiate: dominant = 71.7° ± 8.5° vs nondominant = 61.2° ± 6.9°, P = .001). However, no significant differences were detected in HRVΔ when compared across age groups (P = .511).
CONCLUSIONS
Consistent with studies involving overhead throwing athletes, tennis players demonstrated significantly greater measures of HRV in the dominant limb. Further, the development of HRV asymmetries appear to have occurred prior to the teenage years as no changes were observed in HRVΔ between age groups.
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