Comparison of hip and knee strength in males with and without patellofemoral pain

Objectives: The primary purpose of this study was to compare hip strength in males with and without patellofemoral pain (PFP). The secondary purpose was to compare knee strength in males with and without PFP. Design: Secondary analysis of cross-sectional data for males with and without PFP from a larger randomized controlled trial examining hip and core versus knee-muscle strengthening for the treatment of PFP. Setting: Laboratory setting. Participants: Sixty-six males with PFP and 36 controls. Main outcome measures: Peak isometric force for the hip abductors, external rotators, internal rotators, extensors, and knee extensors expressed as a percentage of body mass (%BM). Results: No differences existed with respect to any of the hip strength measures (P>.05). Males with PFP demonstrated almost 17% less knee extensor strength than controls (mean difference=7.3 %BM; 95% confidence interval, 1.3-13.4 %BM; t=2.41; P=.02). Conclusions: Unlike females, males with PFP did not demonstrate hip muscle weakness. However, differences did exist with knee extensor strength. These data provide preliminary evidence for the potential need for sex-specific interventions for individuals with PFP.