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Published on: May 1, 2018
Hip adduction strength and provoked groin pain: A comparison of long-lever squeeze testing using the ForceFrame and
Mathias F Nielsen1, Kristian Thorborg1, Kasper Krommes1
1Sports Orthopedic Research Center - Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital - Amager and Hvidovre, Hvidovre, Denmark.
Objectives:
To compare long-lever squeeze testing using the ForceFrame and the Copenhagen 5-Second-Squeeze test (5SST) for assessment of hip adduction strength and provoked groin pain in elite male soccer players.
Design:
Cross-sectional study.
Setting:
Pre-season testing at facilities of a Danish professional 1st tier soccer club and academy.
Participants:
Elite male soccer players (n = 83, mean age; 16 ± 2.7 years) from U13, U14, U15, U17, U19 and senior teams cleared for full training and match participation.
Main Outcome Measures:
Maximum isometric hip adduction strength (Nm/kg) and provoked groin pain (NRS 0-10).
Results:
Hip adduction strength was 16% lower in the ForceFrame. A Bland-Altman plot showed a systematic bias (-0.47 Nm/kg, 95% CI [-0.57; -0.38]) and lack of agreement (95% limits of agreement: -1.31; 0.39 Nm/kg). In the ForceFrame, provoked groin pain was less intense (median NRS 0 [IQR: 0-1] vs. 5SST: 1 [IQR: 0-3], p < 0.001) and reported by fewer players (NRS >0) (27% [n = 22] vs. 5SST: 61.4% [n = 51], p < 0.001).
Conclusions:
The ForceFrame and the 5SST lack agreement and are not interchangeable methods. This may have implications when selecting a method for screening and detecting early groin problems in male soccer players.

