Knee injuries are common in adolescent female football. Self-reported previous
knee injury and low
Knee injury and
Osteoarthritis Outcome Score (KOOS) are proposed to predict future
knee injuries, but evidence regarding this in adolescent female football is scarce. The aim of this study was to investigate self-reported previous
knee injury and low KOOS subscale score as risk factors for future
knee injuries in adolescent female football. A sample of 326 adolescent female football players, aged 15-18, without
knee injury at baseline, were included. Data on self-reported previous
knee injury and KOOS questionnaires were collected at baseline. Time-loss
knee injuries and football exposures were reported weekly by answers to standardized text-message questions, followed by injury telephone interviews. A priori, self-reported previous
knee injury and low KOOS subscale scores (< 80 points) were chosen as independent variables in the risk factor analyses. The study showed that self-reported previous
knee injury significantly increased the risk of time-loss
knee injury [relative risk (RR): 3.65, 95% confidence (CI) 1.73-7.68; P < 0.001]. Risk of time-loss
knee injury was also significantly increased in players with low KOOS subscale scores (< 80 points) in
Activities of Daily Living (RR: 5.0), Sport/Recreational (RR: 2.2) and Quality of Life (RR: 3.0) (P < 0.05). In conclusion, self-reported previous
knee injury and low scores in three KOOS subscales significantly increase the risk of future time-loss
knee injury in adolescent female football.