The clinical assessment of hip muscle strength in professional rugby union players

Groin/hip injuries are prevalent in rugby union (RU). Assessment of hip muscle strength is important when designing bespoke injury prevention and rehabilitation programmes. Objective: The primary aim of this study was to determine normative values of hip muscle strength in elite-level RU players. A secondary aim of this study was to compare the Copenhagen Hip and Groin Outcome Score (HAGOS) between players with and without a history of groin/hip injury. Design: Cross-sectional cohort study. Setting: Professional RU club. Participants: 58 male professional RU players competing in the PRO14 league elite club level competition. Main outcome measures: Handheld dynamometry eccentric strength values of hip abduction (ABD), adduction (ADD), internal rotation (IR) and external rotation (ER), HAGOS. Results: Players' dominant (DOM) and non-dominant (NDOM) hip strength values were, 2.38 and 2.34 N m/kg for ABD, 2.79 and 2.71 N m/kg for ADD, 2.69 and 2.55 N m/kg for IR, and 2.65 and 2.54 N m/ kg for ER. ADD:ABD strength ratio was 1.17 +/- 0.26 for the DOM limb and 1.16 +/- 0.24 for the NDOM limb. There was no clinically significant difference in strength between players' DOM and NDOM limbs. Players with a history of groin/hip injury scored lower on four of the HAGOS subscales (pain; symptoms; sport; quality of life) compared to those without a history of groin/hip injury. Conclusions: This study may help establish normative hip strength and HAGOS values for elite-level RU players. The results presented have important implications for the assessment of hip muscle strength and could provide clinical markers for return-to-play following injury. (c) 2021 Elsevier Ltd. All rights reserved.