Static foot pronation as a risk factor for lower limb overuse injury: A systematic review and meta-analysis

Abstract

Background: Static foot pronation has long been considered as a risk factor for lower limb overuse injuries, such as Medial Tibial Stress Syndrome, Patellofemoral Pain and Stress Fractures. However, no single source available has systematically appraised and summarised the literature to evaluate this proposed relationship. The aim of this systematic review was to investigate static foot pronation as a risk for lower limb overuse injury. Methods: A systematic search was performed across multiple electronicdatabases (Medline, CINAHL, EmbaseandSportDiscus) to identify prospective studies that investigated static foot pronation (measured quantitatively) as a risk factor for lower limb overuse injury. Studies were assigned into one or both of two groups based on the method of assessing foot posture: (i) static foot pronation assessment or (ii) dynamic foot function assessment. This review presents the results of the studies from (i) static foot pronation assessment. Two reviewers appraised the included studies using an adapted version of the Epidemiological Appraisal Instrument (EAI).Wherepossible, effectswere expressed as standardisedmean differences (SMD) or risk ratios (RR), with 95% confidence intervals, for continuous and nominal scaled data, respectively. Results: Twenty-one studies were included and the appraisal assessment indicated that most studies were of moderate quality. Static foot pronation was a small but significant risk factor for the development of both Medial Tibial Stress Syndrome and Patellofemoral Pain. Static foot pronation variables associatedwith development of lower limb overuse injuries included Navicular Drop, the Foot Posture Index and Calcaneal Eversion Angle. Significant effects ranged from SMDs of 0.28–0.62 for continuous scaled measures and from RRs of 0.97–1.25 for nominal scaled measures. Several non-significant findings were also reported for a pooled group of Unspecified Lower Extremity Injury, Foot and Ankle Injury and Stress Fractures. Discussion: Findings were limited and in some cases inconsistent, however, differences inmeasures of static foot pronationwere identified to increase the riskof lower limboveruse injury, although the significance is small in effect. It is unclear at this stage whether these risk factors can bemeasured reliably in clinic orwhether they will be predictive of dynamic function. As a result, they should be considered as part of a multifactorial injury risk assessment and not used as stand alone measures.