Review Br J Sports Med 2010;44:1035–1046. doi:10.1136/bjsm.2009.066977 1035 1 School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Australia 2 Australian Institute of Sport, Canberra, Australia 3 McGill University, Montreal, Canada 4 Northern Arizona University, Flagstaff, Arizona, USA Correspondence to Professor Bill Vicenzino, School of Health and Rehabilitation Sciences, Division of Physiotherapy, The University of Queensland, Brisbane QLD 4072, Australia; b.vicenzino@uq.edu.au Accepted 4 November 2009 Foot orthoses and gait: a systematic review and meta-analysis of literature pertaining to potential mechanisms Kathryn Mills, 1,2 Peter Blanch, 2 Andrew R Chapman, 1–3 Thomas G McPoil, 4 Bill Vicenzino 1 ABSTRACT This article systematically reviews the available literature to improve our understanding of the physiological basis for orthoses under the kinematic, shock attenuation and neuromotor control paradigms. The propositions made under these three paradigms have not been systematically reviewed collectively, and as such, there is no single-point synthesis of this clinically relevant body of evidence and somewhat disparate findings. Our comprehensive search strategy yielded 22 papers. Under each paradigm, the role of orthoses with different design features including combinations of posting, moulding and density was analysed. Where possible, data have been pooled to provide an increased level of confidence in findings. The main findings in the kinematic paradigm were that posted non-moulded orthoses systematically reduced peak rearfoot eversion (2.12° (95% CI 0.72 to 3.53)) and tibial internal rotation (1.33° (0.12 to 2.53)) in non-injured cohorts. In the shock attenuation paradigm, it was found that non-posted moulded and posted moulded orthoses produced large reductions in loading rate and vertical impact force when compared with a control and to a posted non-moulded orthosis. The neuromotor control paradigm seems to be the least conclusive in its outcome. Based on our review, this paper concludes with rudimentary guidelines for the prescription of orthosis, that sports medicine practitioners may use in their clinical decision-making process. The need for further research focusing on the role of injury, particularly in neuromotor control modification and long-term adaptation to orthoses, was highlighted. Inshoe foot orthoses are frequently used by cli- nicians 1–3 in the management of overuse injuries. The Australian Podiatry Council and American College of Foot and Ankle Orthopedics and Medicine 3 defi ne “an orthosis as an appliance to support, align, correct deformity or motion of parts of the body.” 1 The conventional kine- matic paradigm, on which these defi nitions are founded, is based on the hypothesis that abnormal pronation of the subtalar joint contributes to lower limb injuries and that orthoses normalise prona- tion and subsequent coupled movements (eg, internal tibial rotation). 4–6 However, this has been questioned. 7–11 In addition to the kinematic paradigm, two other major paradigms have been proposed 8 9 12 13 ; which are essentially the shock attenuation and neuromo- tor control paradigms. The former is based on the concept that the magnitude of force during impact is a major contributor to overuse injuries 14–16 and orthoses are proposed to reduce impact force by acting as a cushioning interface between the ground and foot. More recently, the neuromotor control paradigm has been proposed, whereby an orthosis may optimise performance and minimise muscle activity and fatigue by providing input through the sole of the foot. 8 9 17 A source of confusion for both the researcher and clinician is the array of materials with various properties (type, density or hardness/fi rmness) that are either custom moulded or prefabricated into various shapes, which can be further cus- tomised by the addition of posting or wedging so as to tilt the device from the horizontal. A systematic review of the literature is timely to provide a critically evaluative synthesis of the physiological basis for orthosis therapy during gait under the kinematic, shock attenuation and neuromotor control paradigms. There is no other single source of evidence of the data synthesised from these paradigms, although there are iso- lated systematic reviews without meta-analyses available. 8 12 18–21 This will assist clinicians in their prescription and fitting of orthoses and highlight areas for future research. METHODOLOGY Search strategy We undertook a comprehensive, sensitive literature search strategy of Sportsdiscus, Medline, Cinahl, PubMed, Cochrane and Pedro databases from 1971 to September 2008 (fig. 1). Keywords used in the search strategy focused on the three identified par- adigms: “ortho*, insole, shoe, foot, electromyogra- phy (EMG), muscle activity, biomechanics, kinetic, kinematic, shock attenuation, shock absorption, overuse injur*, leg, lower limb,” with no language restriction. Reference lists of reviews in similar top- ics and papers that met the inclusion criteria were hand searched (K.M.). Titles and (where necessary) abstracts retrieved by initial search were screened (K.M.), with only clinical trials meeting initial cri- teria considered for further review. Inclusion and exclusion criteria Included studies focused on the mechanism of action, rather than efficacy. Excluded were cohorts with neurological (eg, cerebral palsy), systemic (eg, diabetes and rheumatoid arthritis) and degenera- tive (eg, osteoarthritis) conditions, because these may complicate the analysis of gait. on May 6, 2020 by guest. Protected by copyright. http://bjsm.bmj.com/ Br J Sports Med: first published as 10.1136/bjsm.2009.066977 on 8 December 2009. Downloaded from