EP9.10 Gait Biomechanics in Hip Dysplasia Evaluated Using Triaxial Accelerometry
Abstract
Abstract Background Hip dysplasia leads to abnormal joint biomechanics, primarily due to structural instability and altered load distribution. Although the static radiographic features of dysplasia are well described, dynamic alterations during gait remain less studied. Triaxial accelerometry using wearable inertial sensors allows objective evaluation of joint stability and movement patterns during walking. Purpose To evaluate gait stability using triaxial accelerometry in patients with symptomatic hip dysplasia and compare the results with those of healthy hips. Methods A case–control study was conducted including 16 symptomatic hips with dysplasia and 16 healthy hips as controls. Dysplasia was defined radiographically as a lateral center-edge angle (Wiberg) <25°, Tönnis angle >12°, and acetabular coverage <80%. Demographic variables including age, sex, and body mass index (BMI) were recorded. Triaxial accelerometry was assessed using inertial sensors integrated in the Trigno Lite system (Trigno Wireless System, Delsys, Inc., Boston, MA, USA). Acceleration during gait was measured in three axes: axial (X), anteroposterior (Y), and mediolateral (Z). Each participant walked along a straight 20-m path at a self-selected pace. A global acceleration magnitude was calculated, and vector components in each direction (axial, anteroposterior, and mediolateral) were compared between groups. Statistical analysis was performed using the Wilcoxon test, with significance defined as p < 0.05. Results Mean patient age was 27 years, all participants were female, and mean BMI was 25.8. Significant differences were observed between dysplastic and healthy hips in triaxial acceleration patterns. Patients with hip dysplasia demonstrated statistically significant differences (p < 0.05) in axial, anteroposterior, and mediolateral acceleration components, as well as in overall acceleration magnitude during gait. Conclusion Patients with hip dysplasia demonstrate altered gait biomechanics compared with healthy individuals. Triaxial accelerometry provides an objective method to evaluate dynamic hip instability during walking and may represent a useful tool for assessing functional impairment in dysplastic hips.