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.
Lankhorst 2016. Factors that predict a poor outcome 5–8 years after the diagnosis of patellofemoral pain: a multicentre observational analysis.
Nimon 1998. Natural history of anterior knee pain: a 14- to 20-year follow-up of nonoperative management.
Sandow 1985. The natural history of anterior knee pain in adolescents.