Journal of Electromyography and Kinesiology 14 (2004) 43–47 www.elsevier.com/locate/jelekin Linking latest knowledge of injury mechanisms and spine function to the prevention of low back disorders Stuart M. McGill Faculty of Applied Health Sciences, Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1 Abstract While several sophisticated scientific approaches have been employed to understand low back function and injury mechanisms, very few have been broadly used to develop and justify injury prevention strategies. This paper looks beyond the linked segment model, and the lessons learned from this biomechanical approach, to consider the application of more sophisticated approaches. These include modelling approaches with greater anatomical and biological fidelity, fusing the lessons learned from the areas of tissue mechanics and concepts of spine stability, together with some studies that have examined several characteristics including psychosocial, physiological and personal variables. The objective is to better link recently discovered mechanisms of injury and spine tissue health with injury risk reducing approaches. # 2003 Elsevier Ltd. All rights reserved. Keywords: Low back; Injury; Prevention; Evidence based; Ergonomics; Biomechanics 1. Introduction While several sophisticated scientific approaches have been employed to understand low back function and injury mechanisms, relatively few have been used to develop, justify and implement workable injury pre- vention strategies. Generally, biomechanical analyses using link segment approaches have dominated in the formulation of currently popular recommendations such as ‘‘keeping the load close’’ for manual material handlers, reducing cumulative loads from repetitive work, and reducing deviated postures with external force exertions where the transmissible vector is allowed to operate through a substantial moment arm. All of these examples have helped reduce tissue loading and the resultant incidence of back injury. But the ‘‘more sophisticated’’ efforts of many have pushed the frontier of basic science forward. The focus of this paper is to include the consideration of higher concepts of mechanics, obtained from several perspectives, that link recently discovered mechanisms of injury with risk reducing approaches. It is not intended to provide an exhaustive review, but rather provide a few examples to motivate further interest. For the reader interested in much greater development of the issues together with the synthesis involving several disciplines, they are directed to my recent book [9]. 2. Beyond the linked segment model Historically, the predictions of linked segment mod- els have demonstrated the importance of reducing joint moments and the resultant joint compression and shear forces assisting the safer design of a specific job or task. Specifically, reducing reaches during materials handling reduces the low back moment and subse- quently low back loads both in theory and in practice [8]. Developing the principle further, three-dimensional linked segment approaches demonstrated how obli- quely applied transmissible forces not directed through a joint center lead to mechanical overload of tissues. Push and pull exertions fall into this category. Interest- ingly, there are many cases where ergonomic assists have been employed, but workers not understanding this principle failed to benefit from the joint sparing opportunities offered by the devices [9]. As a result the ergonomic intervention was less effective leading to the additional peril of the study being incorporated into an epidemiological meta-analysis review and sub- sequently supporting an inappropriate conclusion. 1050-6411/$ - see front matter # 2003 Elsevier Ltd. All rights reserved. doi:10.1016/j.jelekin.2003.09.012