Is hip muscle weakness a predisposing factor for patellofemoral pain in female novice runners? A prospective study

Background: Hip muscle weakness has been proposed to contribute to patellofemoral malalignment and the development of the patellofemoral dysfunction syndrome (PFDS). However, from the retrospective studies that have addressed this issue, it is still unclear if hip muscle weakness is a cause or a consequence of PFDS.Purpose: This study was undertaken to investigate if hip muscle weakness is a predisposing factor for the development of PFDS.Study Design: Cohort study (prognosis); Level of evidence, 2.Methods: Before the start of a 10-week "start to run" program, the isometric strength of the hip flexor, extensor, abductor, adductor, and external and internal rotator muscles was measured in 77 healthy female novice runners. During the 10-week training period, patellofemoral pain was diagnosed and registered by an orthopaedic surgeon.Results: Statistical analysis revealed that there was no significant difference in strength of any of the assessed hip muscle groups between the runners who did and did not develop PFDS. Logistic regression analysis did not identify a deviation in strength of any of the assessed hip muscle groups as a risk factor for PFDS.Conclusion: The findings of this study suggest that isometric hip muscle strength might not be a predisposing factor for the development of PFDS.