The Relationship Between the Hindfoot Angle and the Medial Longitudinal Arch of the Foot

Introduction: The relationship of hindfoot valgus and the medial longitudinal arch (MLA) is a well-known parameter for the evaluation of the foot deformities. In this study, we evaluated the relationship between the hindfoot angle and the MLA and the effect of these parameters on the development and general joint laxity of the subjects. Methods: Two-hundred-sixty-one volunteers who had no foot pain or major foot deformity were examined. The age range of the volunteers was 4 to 20 years. For each subject, the right foot was evaluated for the clinical hindfoot angle and footprint analysis. General ligamentous laxity also was recorded. Arch index and valgus index were used for the evaluation of the footprint analysis, and the valgus angle was measured clinically. Results: The average heel valgus angle for all subjects was 5.2 (SD 3.3) degrees. The means of valgus index and arch index were 3.34 (SD, 5.6) and 0.7 (SD, 0.2), respectively. Although there was a positive correlation between the valgus angle and valgus index (p = 0.027), the arch index was not found to be correlated with these values. Positive correlation between joint laxity and arch height also was demonstrated (p < 0.05). Conclusions: We concluded that the hindfoot angle and MLA height must be considered separately in clinical practice, particularly in the management of childhood pes planus.