Prognosis of Patellofemoral Pain: A Systematic Review With Evidence- and Gap-Map

Abstract

OBJECTIVE: To systematically appraise current prognostic factor literature for patellofemoral pain (PFP). DESIGN: Systematic review with evidence- and gap-map. LITERATURE SEARCH: PubMed, CINAHL complete, PEDro, Scopus, SPORTDiscus, Embase, Cochrane Database of Systematic Reviews, and Web of Science (from inception to April 2024). STUDY SELECTION CRITERIA: Included participants were those with symptoms consistent with PFP and an average age ≤45 years. Eligible studies were longitudinal cohort studies and randomized controlled trials with a true "wait-and-see" group that measured at least 1 outcome variable at 2 time points and at least 1 potential prognostic factor at baseline. DATA SYNTHESIS: Prognostic factors were iteratively grouped relative to 7 categories and mapped by population and follow-up. RESULTS: Ten longitudinal cohort studies and 12 randomized controlled trials were included. The most frequently evaluated prognostic factors were sociodemographic (n = 21), anthropometric (n = 21), and symptoms and function (n = 19). Fewer studies evaluated biomechanics (n = 12), behavioral (n = 11), psychological (n = 6), and neurobiological (n = 4) factors. Most studies examined the general population (n = 13), with fewer studies in specific populations (adolescents, n = 4; military, n = 2; runners, n = 2; university athletes, n = 1). Most studies evaluated short-term (≤3 months; n = 9) or long-term (>1 year; n = 11) follow-up, with only 2 studies evaluating medium-term follow-up (3 months to 1 year). CONCLUSION: Sociodemographic, anthropometric, and symptoms and function factors were the most studied prognostic factors for PFP. Neurobiological, psychological, biomechanical, and behavioral factors were understudied. Additional studies are needed to identify prognostic factors in specific populations with high incidence of PFP. A comprehensive understanding of prognostic factors may inform development and implementation of evidence-based interventions. J Orthop Sports Phys Ther 2025;55(10):1-10. Epub 8 September 2025. doi:10.2519/jospt.2025.13491.

Keywords: evidence and gap map; knee; patellofemoral pain; systematic review.