Trunk muscle endurance in individuals with and without patellofemoral pain: Sex differences and correlations with performance tests

Objectives: To compare trunk muscle endurance among females and males with and without patellofemoral pain (PFP), and to investigate the correlations between trunk muscle endurance and performance of the single leg hop test (SLHT) and forward step-down test (FSDT). Design: Cross-sectional. Setting: Laboratory-based study. Participants: 110 females and 38 males with PFP, 61 females and 31males without PFP. Main outcome measures: Anterior and lateral trunk muscle endurance were assessed with the prone and bilateral side-bridge tests, respectively. Performance during the SLHT and FSDT was also assessed. Results: Lower anterior and lateral trunk muscle endurance were identified in females (p <.001; d = −0.74 to −0.86), but not in males (p ≥.806; d = −0.04 to 0.05) with PFP as compared to sex-matched controls. Moderate to large, positive correlations between anterior and lateral trunk muscle endurance with performance in the SLHT and FSDT were identified in females (r =.27 to.50; p <.004) and males (r = 0.27 to 0.59; p <.031) with PFP and females without PFP (r = 0.26 to 0.40; p <.044). Conclusion: Our findings highlight that assessing trunk muscle endurance is advised in females with PFP. Trunk muscle endurance of individuals with PFP may have a role in the performance of hopping and stepping down tasks.