Relationship between Pes Planus Foot Type and Postural Stability

Objective

To investigate whether there is a correlation between the degree of pes planus foot deformity and postural stability.

Design

Prospective correlation study.

Setting

Sheffield Hallam University, UK

Participants

Eight healthy volunteers (15 feet) with pes planus foot type. Main Outcomes Measures: Pes planus was defined by the Navicular Drop test (NDT) where a drop >10mm was regarded as pes planus. The SMS Healthcare Balance Performance Monitor (BPM) was used to measure static postural stability using the mean sway number in the lateral and anterior-posterior directions where the higher the sway number the higher the instability.

Results

In the anteroposterior direction there is a good correlation, (spearman's rank = 0.670) which is statistically significant (p= 0.006) indicating that as the degree of pes planus increases the degree of postural stability decreases. In the lateral direction there is a good to excellent correlation, (spearman's rank = 0.880) which is statistically significant (p= 0.01) indicating that as the degree of pes planus increases the degree of postural stability decreases.

Conclusions

As the degree of pes planus deformity increases the degree of static postural stability decreases. These findings may have important implications for clinical practice and future research.