Prenatal Sonographic Features and Postnatal Outcome of Congenital Posteromedial Bowing of Tibia: An Experience from a Tertiary Fetal Medicine Center

Abstract

A series of 18 fetuses were identified from the archives, between 2004 and 2013 with findings of unilateral shortening of the tibia and fibula, an acutely dorsiflexed foot and posteromedial bowing of the tibia and fibula. The median gestational age at diagnosis was 23 weeks (range 20-29 weeks). The discrepancy in length between the affected and contralateral tibia varied from 9 to 33 %. Data on pregnancy outcome were available for 14 (78 %) of 18 fetuses. Four patients opted for termination of pregnancy. All the live born babies (10/14) were followedup postnatally and were well at a median age of 28 months (6-63 months) with milestones appropriate for age at the time of writing. Spontaneous resolution was noted in all the cases and none of them required surgical correction for limb discrepancy so far. Congenital posteromedial bowing of the leg is a benign entity whose outcome includes spontaneous resolution of the angular deformity, albeit with some residual limb length discrepancy and ankle valgus which may need orthopedic intervention around 6-7 years of age. Awareness of this condition helps in making the diagnosis prenatally and in counseling the couples about the prognosis and management options available.