The effect of 6 weeks of custom-molded foot orthosis intervention on postural stability in participants with ≥7 degrees of forefoot varus

Objective: Postural stability (PS) was assessed in a group of participants with 7 degrees of forefoot varus (FV) after 6 weeks of custom-molded functional foot orthosis (FO) intervention to investigate the effect of FO intervention in a population that may have decreased PS due to their foot structure. Design: A force platform was used to assess right and left single-limb stance position and eyes open and eyes closed condition PS. Setting: PS was assessed in a biomechanics research laboratory. Participants: Twelve participants with ! 7 degrees of FV (MFV) and 5 participants with < 7 degrees of FV (LFV) participated in the study. Interventions: PS of the MFV group was assessed initially when FOs were received and after 6 weeks of FO intervention. The LFV group PS was assessed during initial and 6-week testing sessions. Main Outcome Measures: The root mean square of the center of pressure velocity was used to quantify single-limb stance PS during no FO and FO conditions. Results: LFV group PS did not change significantly (P = 0.829) over the 6-week time period. Significant improvement was, however, reported in the MFV group anteroposterior (P = 0.003) and mediolateral (P = 0.032) PS at the 6-week assessment versus the initial assessment during both the noFO and FO conditions. Conclusions: Six weeks of FO intervention may significantly improve PS in participants with >= 7 degrees of FV both when wearing FOs and when not wearing FOs.