Development and Validation of the Foot Inclinometer: A Novel Device for Assessing Standing Foot Posture

Background: Accurate assessment of foot posture is crucial in clinical and research settings for diagnosing and managing various lower limb ailments. Traditional methods, such as the Foot Posture Index (FPI), are prone to manual errors and inter-rater variability, highlighting the need for an innovative and reliable tool for foot posture measurement. This study introduces the Foot Inclinometer (FI), a novel device designed to provide objective, real-time measurements of static foot posture using sensor technology. Objective: To develop and validate the Foot Inclinometer as a reliable and efficient tool for assessing foot posture in a clinical setting, with minimal human error and cost. Methods: A cross-sectional study was conducted with 40 participants (17 males, 23 females) aged 20–60 years. The Foot Inclinometer consists of four pressure sensors placed on anatomical landmarks (first metatarsal, fifth metatarsal, midfoot, and calcaneum) and an accelerometer sensor on the Achilles tendon. Participants stood on the soles while a proximity sensor was held to the Achilles tendon for calibration. The device displayed foot posture (pronated, supinated, or neutral) and the degree of tilt. Data were collected for statistical analysis. Results: The study found that 64% of participants had pronated feet, 24% had neutral feet, and 12% had supinated feet. Age-related variations in foot posture were observed, with a higher prevalence of pronated feet in older age groups. The results were consistent with previous research, demonstrating the Foot Inclinometer's ability to assess foot posture accurately and consistently. Conclusion: The Foot Inclinometer is an effective, low-cost, and easy-to-use device for assessing static foot posture. It reduces human error and provides objective measurements, making it a valuable tool for clinicians and researchers. Further studies are recommended to establish reference values across different age groups and populations and to explore its application in dynamic foot assessment.