Is there a subgroup of females with patellofemoral pain syndrome likely to benefit from proximal control exercises?

Introduction Patellofemoral pain syndrome (PFPS) is one of the most popular complaints among young females. Proximal hip control exercises can improve hip strength and reduce the stresses and pain. However, there is a lack of studies that investigate predictors of the success of proximal hip control exercises in this disorder. This predictive validity diagnostic trial aimed to investigate the effect of body mass index, age, duration of symptoms, and knee angle valgus on proximal control exercise success to improve hip muscle abductors and external rotator isometric strength. Methods Fifty females with PFPS recruited from Ain shams University Hospital with a mean age of 25 years received proximal control exercises (transversus abdominis and multifidus activation, hip extensor, abductor and external rotator strengthening). Participants were assessed for hip strength using a handheld dynamometer, and dynamic knee valgus via video analysis using the Kinovea v.0.8.15 computer program. Results Age was found to be a predictor of success in hip abductor strength, and duration of symptoms a predictor of success in hip external rotator strength with proximal control exercises in patellofemoral pain syndrome female individuals, with no specific cut-off points. Conclusions Proximal control exercises can improve hip strength in females with PFPS with no specific cut-off points for the significant predictors found (age and duration of symptoms).