Congenital Posterior Dislocation of Fibula with Pes Valgus Deformity.

Congenital posterior dislocation of fibula with pes valgus deformity is a rare disorder in children and has not been reported in English literature. The parents recognize it when the child starts to bears weight as the foot appears normal non-weight bearing but on standing or bearing weight it goes into valgus. As the foot is manually correctable to neutral plaster correction does not suffice and surgery becomes essential. The differential diagnosis of this condition is the well-described congenital diastasis of inferior tibiofibular joint, where the foot is with equinovarus deformity. We are reporting a child of 2 years of age who presented to us walking on the medial border of sole, a valgus deformity on walking and no other congenital anomalies. We operated upon this case of congenital posterior dislocation of fibula with pes valgus deformity and are reporting it for the abnormal patho-anatomy, surgical steps followed and treatment protocol adopted by us. © Indian Orthopaedics Association 2020.