Classifying Foot Arch Morphologies Using High-Sensitivity Pressure Mat Technology: Prevalence Estimates and Associations With Pain, Activity Limitations, and Patient Characteristics in a Community-Based Adult Sample.

Introduction There is a lack of consensus in the literature regarding the clinical understanding of foot arch contact variations in the general population, as most studies have focused on specific demographic groups or risk factors. This limits the ability of clinicians to communicate risk and interpret arch-related findings in diverse patient populations. This cross-sectional study evaluated the use of a novel pressure mat method to categorize adults as having flatfoot, high arch, or normal feet in a large convenience sample and examined demographic and medical characteristics associated with these arch variations. Methods A high-sensitivity pressure mat measured midfoot contact areas during static bipedal stance in 1,015 adults (2,030 feet). Feet were categorized as flat (midfoot area > mean + 1 SD), high arch (midfoot area < mean - 1 SD), or normal (± 1 SD). Demographics, comorbidities, activity limitation, and foot pain were collected via medical records and surveys. Associations were analyzed using chi-square tests and multivariable logistic regression, adjusting for age, gender, race/ethnicity, education, income, activity level, BMI, hypertension, diabetes, and arthritis. Results Prevalence was 11.1% (113 participants) for at least one flatfoot (36, or 3.5%, bilateral) and 18.3% (186 participants) for at least one high arch (88, or 8.7%, bilateral). Flatfoot was significantly associated with male sex (AOR = 5.0, 95% CI: 2.8-8.9), African American race (AOR = 5.7, 95% CI: 3.0-10.8), other race (AOR = 3.8, 95% CI: 1.2-12.3), obesity (AOR = 5.1, 95% CI: 1.7-15.6), and arthritis (AOR = 2.0, 95% CI: 1.2-3.6); high arch showed inverse associations. Participants with flatfoot reported significantly higher rates of activity limitation (27, or 24.3%) and foot pain compared to normal-arch participants, while high-arch participants reported less pain and more activity than those categorized as having normal arches. Conclusion Using a high-sensitivity pressure mat, we estimated flatfoot prevalence at 11.1% and high-arch prevalence at 18.3% in a community-based adult sample. Foot morphology categories demonstrated significant associations with demographics, comorbidities, and, for flatfoot, activity limitations and foot pain, both aligning with and extending prior literature. To our knowledge, this study is among the first to apply pressure mat technology for arch classification in a large, diverse sample, suggesting potential utility for clinical screening and risk communication using these estimated baseline measures. Pressure mats may offer a rapid, non-invasive screening tool for foot arch assessment, though validation against clinical examination is needed before clinical implementation.