The Effect of Subtalar Joint Pronation Amount on Lower Extremity Alignment and Performance

Foot Posture Index 6 (API-6) is a clinical diagnostic tool that broadly measures whether a foot is in neutral, supination or pronation posture. During the evaluation, individuals' static standing postures in a comfortable position are observed and scored. When using API-6, researchers visually evaluate the foot according to 6 criteria, each rated on a 5-point (-2 to +2) Likert scale. Each item is scored between -2 (supination) and +2 (pronation) and 0 (for neutral position), with the total score being between -12 (high degree of supination) and +12 (high degree of pronation). The grouping of reference values showing foot posture can be summarized as follows; Neutral position from 0 to +5, pronation position from +6 to +9, hyperpronation position from +10 to +12, supination position from -1 to -5, and supination position from -6. It shows a high degree of supination position up to -12. Higher scores represent a more pronated foot posture.