Background Patellofemoral pain syndrome (PFPS) is the most common complaint in female volleyball players. Larger quadriceps femoris angle (Q angle) has been implicated as a source of patellofemoral pain but values measured during functional tasks (dynamic Q angle) have not been adequately documented in the literature.

Objective With this study, we attempt to determine whether excessive Q angle during a functional task is related with PFPS.

Design A correlational study.

Setting The study was conducted among high performance female athletes all participating in the Portuguese A1 Division.

Participants 50 female volleyball players participated. They were included in one of two groups, according to the presence or absence of patellofemoral pain.

Interventions Static Q angle was measured using a goniometer. Subjects were videotaped during the execution of simple functional tasks and dynamic Q angle was determined ‘a posteriori’ using a video analysis program.

Main outcome measurements A correlation was examined between static and dynamic Q angle and the prevalence of patellofemoral pain.

Results When averaged across all conditions, the average dynamic Q-angle was significantly higher in the PFP group compared to the control group (34.9° vs 22.3°). We found a relationship between larger dynamic Q angles and PFPS (r=-0.517) that remained significant (p<0.01) when the static Q angle was normal.

Conclusions The results substantiate the belief that lower extremity motion during dynamic tasks may increase Q-angle and the lateral force acting on the patella, even on individuals with a ‘normal’ static Q-angle. Static Q-angle measurements in this study showed little relationship to dynamic Q-angle measurements and with the presence of PFP.