Forefoot varus predicts subtalar hyperpronation in young people

Subtalar joint hyperpronation is a foot misalignment that has been associated with several musculoskeletal injuries. Forefoot varus is thought to result in subtalar hyperpronation during weightbearing circumstances. However, few studies have aimed to verify whether there is a significant relationship between forefoot alignment and subtalar hyperpronation. Moreover, no study has attempted to verify whether forefoot varus can predict subtalar hyperpronation in young individuals. Therefore, the purpose of this study was to verify whether forefoot varus can predict subtalar hyperpronation, measured using the rearfoot eversion angle test, the navicular drop test, and the Foot Posture Index (FPI), in young people.

Fifty-four healthy adolescents volunteered for this study (28 boys and 26 girls). A single examiner evaluated the forefoot angle, rearfoot angle, navicular drop, and FPI of each participant. Statistical analysis included the Pearson correlation test and a linear regression analysis to establish the relationship between the variables.

These results showed a high positive correlation between forefoot varus and rearfoot angle (r = 0.86; P < .001), navicular drop (r = 0.76; P < .001), and FPI (r = 0.82; P < .001). Moreover, the forefoot varus variable was able to predict 74% of the variability in the rearfoot angle, 58% in the navicular drop, and 67% in the FPI (P < .001).

These findings support previous assumptions that individuals with forefoot varus present subtalar hyperpronation. Clinicians should not overlook forefoot alignment when prescribing foot orthoses for treating patients with foot misalignments.