Orthotics are used to treat a number of foot and ankle pathologies, but require the use of supportive footwear. Alternatively, the barefoot condition enhances sensation from the plantar foot leading to gait adaptations that may influence injury prognosis and incidence. Recently, a barefoot orthotic (Hozhoni Balance Rail®) was designed to adhere to the plantar surface rather than being secured inside footwear; thus, potentially allowing for the benefits of the barefoot gait, while also providing the stability of an orthotic.
PURPOSE: To determine if the commonly observed barefoot gait adaptations were found when walking and running with the barefoot orthotic.
METHODS: 12 healthy habitually shod runners (7 men and 5 women, age: 25 ± 3.8 yr; height: 1.58 ± 0.15 m; mass: 68.1 ± 8.9 kg) participated in this study. Gait kinematics and kinetics were analyzed as participants performed 10 over-ground trials of running and walking in running shoes (SHOD), barefoot (BF), and while wearing the barefoot orthotics (BF ORTHO). Kinematic data was obtained via 3D motion analysis and ground reaction force (GRF) data were captured as subjects ran across a runway with an embedded force plate. Kinematic and kinetic differences between the SHOD, BF and BF ORTHO conditions for both walking and running were analyzed using repeated measures ANOVA tests.
RESULTS: There were no significant differences between the BF and BF ORTHO conditions in terms of gait kinematics or kinetics in either walking or running, indicating that the barefoot orthotic does not interfere with the natural barefoot gait. Consistent with previous research, subjects exhibited decreased stride lengths in the BF and BF ORTHO conditions when walking (BF: 1.38+0.20 m, BF ORTHO: 1.43+0.19 m, SHOD: 1.54+0.17 m, p<0.05 compared to SHOD) and running (BF: 1.98+0.27 m, BF ORTHO: 2.06+0.30 m, SHOD: 2.16+0.31 m, p<0.05 compared to SHOD). Additionally, the BF and BF ORTHO conditions were associated with reduced peak vertical GRFs in walking (BF: 1.16+0.10 m, BF ORTHO: 1.19+0.12 m, SHOD: 1.29+0.11 m, p<0.05 compared to SHOD) and running (BF: 2.29+0.26 m, BF ORTHO: 2.27+0.21 m, SHOD: 2.48+0.22 m, p<0.05 compared to SHOD).
CONCLUSION: The barefoot orthotic does not interfere with the natural barefoot gait, indicating the potential for clinical use while barefoot or without supportive footwear.