Although knee cap pain has traditionally been viewed as self-limiting, the chronic knee pain might persist in 40% of patients after 1-year and up to 91% of patients after 18 years.
In another study 57% of the patients reported unfavourable recovery at 5 to 8 years after treatment.
However, knee cap pain treatments are effective at short-term. Thus, key factors for having a long-term sustained recovery are:
Collins 2013. Prognostic factors for patellofemoral pain: a multicentre observational analysis.
Sandow 1985. The natural history of anterior knee pain in adolescents.