Footwear, Orthoses, and Insoles and Their Effects on Balance in Older Adults: A Scoping Review.

Background: Footwear, orthoses, and insoles have been shown to influence balance in older adults; however, it remains unclear which features, singular or in combination, are considered optimal. The aim of this scoping review was to identify and synthesise the current evidence regarding how footwear, orthoses, and insoles influence balance in older adults. Four electronic databases (MEDLINE, CINAHL, Embase, and AMED) were searched from inception to October 2023. Key terms such as "shoe*," "orthoses," "postural balance" and "older people" were employed in the search strategy. Studies meeting the following criteria were included: (i) participants had a minimum age ≥60 years, and were free of any neurological, musculoskeletal, and cardiovascular diseases; (ii) an active intervention consisting of footwear, foot orthoses, or insoles was evaluated; and (iii) at least one objective outcome measure of balance was reported.

Summary: A total of 56 studies from 17 different countries were included. Three study designs were utilised (cross-sectional study, n = 44; randomised parallel group, n = 6; cohort study n = 6). The duration of studies varied considerably, with 41 studies evaluating immediate effects, 14 evaluating effects from 3 days to 12 weeks, and 1 study having a duration of 6 months. Seventeen different interventions were evaluated, including/consisting of textured insoles (n = 12), heel elevation (n = 8), non-specific standardised footwear and changes in sole thickness or hardness (n = 7 each), sole geometry or rocker soles, contoured or custom insoles and high collar height (n = 6 each), insole thickness or hardness and vibrating insoles (n = 5 each), outsole tread (n = 4), minimalist footwear and slippers (n = 3 each), balance-enhancing shoes, footwear fit, socks, and ankle-foot orthoses (n = 2 each), and eversion insoles, heel cups, and unstable footwear (n = 1 each). Twenty-three different outcomes were assessed, and postural sway was the most common (n = 20), followed by temporo-spatial gait parameters (n = 17). There was uncertainty regarding intervention effectiveness. Overall, features such as secure fixation, a textured insole, a medium-to-hard density midsole and a higher ankle collar, in isolation, were able to positively impact balance. Conversely, footwear with an elevated heel height and the use of socks and slippers impaired balance.

Key messages: There is a substantial body of literature exploring the effects of footwear, orthoses, and insoles on balance in older adults. However, considerable uncertainty exists regarding the efficacy of these interventions due to variability in methodological approaches. Further high-quality research is necessary to determine whether a singular intervention or a combination of interventions is most effective for enhancing balance in older adults.