Adolescent sports injuries

Event start date
Event start time

Arvo building, auditorium F115, address: Arvo Ylpön katu 34

Anu Räisänen

Doctoral defence of M.H.Sc. Anu Räisänen

Adolescent sports injuries: Frontal plane knee control as an injury risk factor and a screening tool

The field of science of the dissertation is Public Health.

The opponent is Professor Reed Ferber (University of Calgary, Canada). Professor Arja Rimpelä acts as the custos.

The language of the dissertation defence is English.

Knee control as a sports injury risk factor among adolescents

The academic dissertation of Anu Räisänen, M.H.Sc., PT, focused on the prevalence of sports injuries among Finnish adolescents as well as knee control as a risk factor for injuries among young floorball, basketball and football players. The studies comprising this dissertation were carried out at the University of Tampere and the Tampere Research Center of Sports Medicine, UKK Institute for Health Promotion Research.

Sports and physical activity-related injuries are the most common injuries among adolescents. There are numerous risk factors for these injuries and when an injury occurs, there are several factors which have contributed to the event. Some risk factors, such as age, cannot be modified. Some factors, such as some attributes of the athlete, can be modified. Knee control can be modified by simple exercises which can be done, for example, as part of warm up. In athletic tasks, such as running and squatting, reduced knee control can be witnessed as knees moving inwards, which is referred to as valgus.

Previous studies have used the vertical drop jump to study reduced knee control as a risk factor for sports injuries. It has been reported that the athletes, who land with knees close to each other (valgus) have a higher risk of injuries than athletes with good knee control.  In popular team sports, such as floorball, basketball and football, sprints and changes in direction are very common. These are performed in a single-leg stance. Physiotherapist, athletic trainers and physician utilise the single-leg squat to assess knee control, but it has not been previously studied whether the single-leg squat performance is associated with a higher risk of injuries.

This dissertation established that one in three adolescents had sustained at least one physical activity-related injury during the previous 12 months. The proportions of injured participants were highest in sports club activities, followed by leisure time physical activities and school sports. Among the adolescent floorball and basketball players (average age 16 years), poor knee control in the single-leg squat was associated with a higher risk of sports injuries. This association was not detected in younger adolescents, 10 to 14 years, who played football.  

This doctoral dissertation has confirmed that poor knee control increases the risk of injuries among adolescent team sport athletes. It is important for the athlete to reduce the risk of injuries by modifying the factors which can be modified. Knee control is a modifiable risk factor. Previous studies have demonstrated that knee control can be improved by simple exercises, which can reduce the risk of sports injuries.


The dissertation is published in the publication series of Acta Universitatis Tamperensis; 2369, Tampere University Press, Tampere 2018. The dissertation is also published in the e-series Acta Electronica Universitatis Tamperensis; 1875, Tampere University Press 2018.

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