Effects Of Using Insoles Of Different Thicknesses In Older Adults: Which Thickness Has The Best Impact On Postural Stability And Risk Of Falling?

BACKGROUND: Postural stability (PS) problems arise as an individual grows older, and as a result, risk of falling (RoF) increases in older adults. The purpose of this study was to examine the effects of insoles of various thicknesses on PS and RoF in older adults.

METHODS: Fifty-six individuals participated in the study. PS and RoF were evaluated both statically and dynamically using Biodex Balance System. PS and RoF assessments were perfomed under five different conditions: 1) barefoot, 2) only shoes, 3) with 5 mm insole, 4) with 10 mm insole, 5) with 15 mm insole. Standard shoes with identical features were used fitting the foot size of the individuals. In order to avoid time-dependent problems, these assessments were re-measured under the same conditions in 3 consecutive weeks. The average of these 3 values were recorded as the individuals' PS and RoF scores.

RESULTS: Insoles of different thicknesses significantly affected static PS [overall, p:0.003; medio-lateral (ML), p:0.021; antero-posterior (AP), p:0.006], static RoF (overall, p:<0.001; ML, p:<0.001; AP, p:<0.001), dynamic RoF (overall, p:0.003; ML, p:0.042; AP, p:0.050) and dynamic PS (overall, p:0.034;AP, p:0.041). However, thickness of the insoles did not have any impact on dynamic PS-ML (p:0.071). Amongst all measurements of static PS-overall, dynamic PS-AP, static RoF-overall, static RoF-ML, dynamic RoF-overall, dynamic RoF-ML, the highest PS scores and the lowest RoF were recorded in case of using 10 mm insole (p<0.05).

CONCLUSIONS: The use of insoles with different thicknesses has been shown to be effective on all RoF and PS measurements (except for dynamic PS-ML). 10-mm-thick insole turned out to be a better option for elderly individuals to increase PS and reduce RoF compared the barefoot, only shoes, 5 and 15 mm insoles. For older adults, 10-mm-thick insoles made of medium-density plastozote may be recommended to help them with a better PS and a reduced RoF.