Biomechanical risk factors for running-related injury differ by sample population: A systematic review and meta-analysis

Highlights

• Sample studied appears to influence which biomechanical variables may be relevant to injury.

• Sex and competitive level should be considered when evaluating running biomechanics.

• Loading rates warrant further investigation as factors in injury for female recreational runners.

• Peak hip adduction and rearfoot eversion may be related to injury in female recreational runners.

Abstract

Background

The role of biomechanical variables of running gait in the development of running related injury has not been clearly elucidated. Several systematic reviews have examined running biomechanics and its association with particular running related injuries. However, due to retrospective designs, inferences into the cause of these injuries are limited. Although prospective studies have been completed, no quantitative analysis pooling these results has been completed.

Methods

A systematic review of MEDLINE, CINAHL, and PubMed was completed. Articles included used prospective study designs, human subjects currently completing a regular running program, and a minimum 12-week follow-up period. Excluded articles had no biomechanical data reported, participants who were beginning runners or military recruits, or had an intervention provided.

Findings

Thirteen studies met these criteria. Pooled analyses were completed if two or more studies were available with samples that investigated the same sex and competition level. A qualitative synthesis was completed when pooled analysis was not possible. Five unique running samples were identified and allowed for pooled analyses of variables in mixed-sex collegiate runners and female recreational runners. Moderate evidence exists for increased hip adduction and reduced peak rearfoot eversion as risk factors for running related injury in female recreational runners. Variables differed in other samples of runners.

Interpretation

A runner's sex and competition level may affect the relationship between biomechanical factors and the development of running related injury. Hip adduction and rearfoot eversion may be important factors related to running related injury in female recreational runners. Further investigation of biomechanical factors in running injury is warranted.

Introduction

Several theories have been postulated as to the etiology of running related injury (RRI) including impact forces (Hreljac, 2004), foot pronation (Davis, 2014), foot strike pattern (Lieberman et al., 2010), and hip muscle function (Barton et al., 2013). This has led to a preponderance of biomechanical studies aiming to identify the specific factors present in individuals' running mechanics that may be related to the development of RRIs. However, many of these studies have been either retrospective or cross-sectional in nature and therefore have limited their ability to determine these as etiological factors in RRI.

Previous reviews have investigated the biomechanical factors that have been related to specific RRIs including patellofemoral pain (Neal et al., 2016), iliotibial band syndrome (Aderem and Louw, 2015), Achilles tendinopathy (Ogbonmwan et al., 2018), and lower extremity tendinopathies (Mousavi et al., 2019), as well as RRI in general (Van Der Worp et al., 2016). These studies have identified some factors that appear to be important to RRI, however, each of these reviews have included both prospective and retrospective studies which limit the ability to conclude if such factors precede RRI development. Further, many of these reviews have only examined particular biomechanical characteristics (Van Der Worp et al., 2016) which may fail to see the interaction between those variables of interest and other joint kinematic and kinetic factors. Some studies have only investigated particular injury types (Aderem and Louw, 2015; Neal et al., 2016; Ogbonmwan et al., 2018) which may result in attributing those biomechanical factors to one type of injury rather than evaluating their overall role in RRI.

Although the biomechanical factors identified in these studies may be important to address clinically in runners who currently have pain or injury with running since successful treatment strategies have been implemented addressing these factors (Cheung and Davis, 2011; Neal et al., 2016; Willy et al., 2012), without further rigorous studies indicating which specific biomechanical factors during running precede RRI, it is very difficult to construct appropriate injury prevention programs for runners. Further, making modifications to running form in runners who have not had previous running injury runs the risk of becoming “guess work” in clinical settings. Therefore, further evidence from prospective studies should support such modifications to running mechanics.

One recent review examined the biomechanical factors associated with RRI from only prospective studies (Ceyssens et al., 2019). It was reported that many biomechanical variables had inconsistent findings across studies which those authors hypothesized were due to heterogeneity in the sample populations, methodologies employed, and outcome variables examined. They also reported that the findings from single studies require further verification in future studies through the use of prospective study designs. Since the sample investigated has been emphasized in other systematic reviews to explain the differences in incidence rates (Videbæk et al., 2015) and injury proportions and locations among runners (Kluitenberg et al., 2015), pooled analyses from similar samples may help further guide these efforts to more precisely define which biomechanical factors are relevant to RRI.

Previous work has examined injury incidence rates (Kluitenberg et al., 2015; Videbæk et al., 2015) and have provided the crucial first step of injury prevention models (van Mechelen et al., 1992). The second step is to study the etiological factors related to RRI. Ceyssens et al. (2019) have attempted to identify biomechanical factors in the etiology of RRI, however, no quantitative synthesis of their results were presented. We believe that completing a quantitative synthesis when possible within the identified samples of runners may provide additional insight into etiological factors in RRI and guide future research efforts.

Thus, the aim of this systematic review is to identify which biomechanical factors during running have prospective evidence linking them to the etiology of RRI in experienced runners. A secondary aim was to complete a meta-analysis on those variables reported in at least two studies with a similar sample that will investigate to what degree within that sample these biomechanical variables are related to RRI.