Comparison of Different Structural Foot Types for Measures of Standing Postural Control

• Published in: The journal of orthopaedic and sports physical therapy Vol. 36; no. 12; pp. 942 - 953
• Main Authors: Tsai, Liang-Ching, Yu, Bing, Mercer, Vicki S., Gross, Michael T.
• Format: Journal Article
• Language: English
• Published: United States 01.12.2006
• Subjects: Adolescent; Adult; Female; Foot - anatomy & histology; Foot - physiology; Humans; Male; Pronation - physiology; Proprioception - physiology; Reproducibility of Results; Supination - physiology; Weight-Bearing - physiology
• ISSN: 0190-6011; 1938-1344
• DOI: 10.2519/jospt.2006.2336

Matched group comparison of 3 subject groups with 3 different foot structures for force plate and clinical measures of postural control. To determine if subjects with different weight-bearing foot structure would demonstrate differences in static standing postural control, and to determine the reliability of study procedures. Weight-bearing foot structure may influence postural control either because of a decreased base of support (supinated foot structure) or because of passive instability of the joints of the foot (pronated foot structure). Young adults were categorized based on weight-bearing foot structure into neutral, pronated, or supinated groups (15 subjects per group). Postural control in single-limb stance with eyes closed was assessed using force plate measures and by measuring duration of single-limb stance on a firm floor and on a balance pad. Force plate measures were normalized center-of-pressure average speed; and standard deviation and maximum displacement in the anterior-posterior and medial-lateral directions. Individuals in the supinated group had significantly greater center-of-pressure average speed, greater maximum displacement in the anterior-posterior direction, and greater SD and maximum displacement in the medial-lateral direction than individuals in the neutral group. The individuals in the pronated group had significantly greater SD and maximum displacement in the anterior-posterior direction, used more trials to complete force plate testing, and had shorter single-limb stance duration than those in the neutral group. Individuals with pronated feet or supinated feet have poorer postural control than individuals with neutral feet, but perhaps through different mechanisms.