RESUMEN
PURPOSE: To examine the effects of different torsional flexibilities of shoes on gait and stability in children who are newly walking. METHODS: Twenty-five children walking 5 months or less were evaluated barefoot and in 4 shoes with different torsional flexibilities (UltraFlex, MidFlex, LowFlex, and Stiff). Gait pattern was assessed using GaitMatII. Stability was determined by the number of stumbles/falls during functional tasks. RESULTS: Stance time was shorter barefoot compared with all shoe conditions (P = .000). Stance time was shorter in UltraFlex than in LowFlex (P = .000). Step width was wider in UltraFlex than in MidFlex and LowFlex (P = .028). Velocity, step length, and the number of stumbles/falls did not differ significantly across shoe conditions. Children walking for 2 months or less had significantly more stumbles and falls than children walking more than 2 months (P = .003). CONCLUSIONS: Stance time and step width differ across shoe conditions. Stability does not differ across shoe conditions.
Asunto(s)
Marcha , Zapatos , Caminata , Fenómenos Biomecánicos , Diseño de Equipo , Femenino , Humanos , Lactante , Masculino , DocilidadRESUMEN
BACKGROUND: In a previous pilot study of "cruisers" (nonindependent ambulation), "early walkers" (independent ambulation for 0-5 months), and "experienced walkers" (independent ambulation for 6-12 months), developmental age significantly affected the children's stability when walking and performing functional activities. We sought to examine how shoe structural characteristics affect plantar pressure distribution in early walkers. METHODS: Torsional flexibility was evaluated in four shoe designs (UltraFlex, MedFlex, LowFlex, and Stiff based on decreasing relative flexibility) with a structural testing machine. Plantar pressures were recorded in 25 early walkers while barefoot and shod at self-selected walking speeds. Peak pressure was calculated over ten masked regions for the barefoot and shod conditions. RESULTS: Torsional flexibility, the angular rotation divided by the applied moment about the long axis of the shoe, was different across the four shoe designs. As expected, UltraFlex was the most flexible and Stiff was the least flexible. As applied moment increased, torsional flexibility decreased in all footwear. When evaluating early walkers during gait, peak pressure was significantly different across shoe conditions for all of the masked regions. The stiffest shoe had the lowest peak pressures and the most flexible shoe had the highest. CONCLUSIONS: It is likely that increased shoe flexibility promoted greater plantar loading. Plantar pressures while wearing the most flexible shoe are similar to those while barefoot. This mechanical feedback may enhance proprioception, which is a desirable attribute for children learning to walk.