Biomechanical variations of lower limb as risk factors of groin pain: A systematic review

Biomechanical variations of lower limb could be responsible for groin pain.

The aim of this review is to evaluate if there is a relationship between having biomechanical variations of the lower limb and suffering from groin pain, and to describe what these influential biomechanical variations are.

This review was registered on Open Science Framework prior to data extraction. A systematic search of PubMed, Embase, Web of Science, Scopus, CINAHL and SPORTDiscus, in addition to manual searches, were conducted. The risk of bias was assessed thanks to the tools "The Joanna Briggs Institute Checklist for Analytical Cross-Sectional Studies" (JBI), and "The Quality in Prognosis Studies (QUIPS)" for longitudinal studies.

15 studies, and the possibility of bias in their design, conduct and analysis were evaluated. Most cross-sectional studies had homogeneous exposure measurements that were valid and reliable. They used standardized criteria and objective methods, but lacked strategies to address confounding factors. Longitudinal studies had low bias in measuring the prognostic factor and in statistical analysis, but high bias in handling confounding factors. A meta-analysis was not performed due to substantial heterogeneity in study populations, measurement techniques, diagnostic thresholds, and outcome definitions, which precluded valid data pooling.

There are no biomechanical variations of the lower limb that can directly cause groin pain. The coxofemoral joint is the most studied for this association, with the alpha angle being the parameter that most influences groin pain when it exceeds 55°.