Knee cap pain is one of the most common knee conditions among adolescents, affecting up to 7% of this population. In adults, knee cap pain affects 17% of runners, and 23% of the general population.
Knee cap pain is two times more likely to affect women than men.
Smith 2018. Incidence and prevalence of patellofemoral pain: A systematic review and meta-analysis.
Boling 2010. Gender differences in the incidence and prevalence of patellofemoral pain syndrome.
Taunton 2002. A retrospective case-control analysis of 2002 running injuries.