Relationship Between One-Leg Standing and Foot Sole Sensation Following Short-Term Immobilization of a Unilateral Lower Extremity.

BACKGROUND

Several studies have suggested that approximately 10 hours of inactivity can reduce motor performance. Specifically, restricted lower limb movement may impair postural stability, subsequently increasing the incidence of falls. However, the relationship between postural sway and its related factors remains unclear. This study investigated the relationship between postural sway in the upright standing position and foot sole sensitivity after short-term immobilization.

METHODS

Healthy young adults were enrolled. Each participant's lower limb was immobilized for 10 hours using a soft bandage and a medical splint made from metal and soft urethane. The sway in the center of the pressure trajectory was measured before and after immobilization. Evaluation parameters included path length, mean velocity, and sway area. Foot sole sensitivity was assessed using an esthesiometer to measure two-point discrimination before cast application and immediately after cast removal.

RESULTS

After cast removal, total and anterior-posterior path lengths, mean velocity and sway area increased, whereas big toe sensitivity decreased. However, no significant correlations were observed among these factors.

CONCLUSIONS

Our results suggest that short-term movement restriction induces acute changes in center of pressure (COP) movement and foot sensitivity. However, the COP movement was not associated with foot sensation, indicating that another factor may contribute to postural sway after cast removal.