Prevalence of Jumper’s Knee Among Nonelite Athletes From Different Sports

BACKGROUND: The prevalence of jumper's knee among nonelite athletes from different sports is unknown. PURPOSE: This study was undertaken to determine the prevalence of jumper's knee in nonelite athletes from different sports and to determine potential risk factors for jumper's knee. DESIGN: Cohort study (prevalence); Level of evidence, 2. METHODS: The authors interviewed 891 male and female nonelite athletes from 7 popular sports in The Netherlands: basketball, volleyball, handball, korfball, soccer, field hockey, and track and field. Using a specially developed questionnaire, information was obtained about individual characteristics (age, height, and weight), training background, previous and actual knee problems, and the VISA-P (Victorian Institute of Sport Assessment-Patella) score. RESULTS: The overall prevalence of current jumper's knee was 8.5% (78 of 891 athletes), showing a significant difference between sports with different loading characteristics. Prevalence was highest among volleyball players (14.4%) and lowest among soccer players (2.5%); it was significantly higher among male athletes (51 of 502 10.2%) than female athletes (25 of 389 6.4%) (χ(2) = 3.91, P = .048). The mean duration of symptoms was 18.9 months (standard deviation SD, 21.6; median value, 12.0; range, 2.0-59.8). The mean VISA-P score of the athletes with jumper's knee was 71.4 (SD, 13.8). Athletes with jumper's knee were significantly younger, taller, and heavier than those without jumper's knee. CONCLUSION: Prevalence of jumper's knee is high among nonelite athletes and varies between 14.4% and 2.5% for different sports. Jumper's knee is almost twice as common among male nonelite athletes compared with female athletes. Different sport-specific loading characteristics of the knee extensor apparatus, a younger age, a taller body stature, and higher body weight seem to be risk factors associated with patellar tendinopathy.