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Information about a piece of news titled Physiotherapists can identify female athletes with high knee valgus angles in vertical drop jumps

Physiotherapists can identify female athletes with high knee valgus angles in vertical drop jumps


This key message is one of the results of a PhD-project from the Oslo Sports Trauma Research Center recently published in Journal of Orthopeadic and Sports Physical Therapy.


Excessive knee valgus has been suggested as being contributory to the anterior cruciate ligament (ACL) injury mechanism.


Previous studies have used the vertical drop jump test to assess knee kinematics and kinetics with the aim of identifying risk factors for injury.


However, these studies have been based on advanced and time-consuming equipment, such as 3-dimensional (3D) motion analysis.


Thus, there is a need for simple and efficient, yet reliable, screening tools to identify athletes who may benefit from injury prevention training.



60 players screened by three physiotherapists

A total of 60 Norwegian elite female football players participated in 2 screening tests; real-time observational screening of a vertical drop jump, where 3 physiotherapists independently scored their frontal plane knee control as being ”good”, ”reduced” or ”poor,” and 3D motion analysis of another vertical drop jump to assess peak knee valgus angles and abduction moments.


Players scored with poor knee control displayed significantly higher valgus angles compared to those scored with good control (10.3° ± 3.4° vs. 1.9° ± 4.3°, p<0.001).


The correlation between observational test scores and objective measures of knee valgus was moderate for all raters (0.54-0.60, p<0.001), whereas the observational test scores correlated poorly with abduction moments (0.09-0.11, p>0.05).


The inter-rater agreement was substantial to almost perfect, with percentage agreement and Kappa correlation coefficients ranging from 70% to 95% and 0.52 to 0.92, respectively.




Physiotherapists can identify athletes with high knee valgus angles


The findings of this study revealed that physiotherapists can identify female athletes displaying high knee valgus angles during a drop-jump landing task using real-time observational screening.


The screening procedures used in the current study are simple and easy to use and implement in a clinical setting, and therefore enable large-scale screening to identify athletes whom may benefit from injury prevention training.


However, the authors emphasize that existing prevention programs have proven effect, and all athletes at the junior and senior level should continue using injury prevention training programs.


This study was led by PhD-candidate and physiotherapist Agnethe Nilstad and her co-workers. Agnethe will defend her PhD-work in the summer 2014.




Download paper in Journal of Orthopeadic and Sports Physical Therapy.