Fetal Fibular Hemimelia

Abstract

The AIUM Practice Guideline for the Performance of an Antepartum Obstetric Ultrasound Examination 1 recommends documenting the presence or the absence of the fetal extremities during the second trimester of pregnancy. At times both upper and lower extremities may be present, and an obvious fetal malformation may not be apparent until all the long bones are carefully measured and evaluated. This can further be challenging when only 1 limb or part of a limb is affected. In the obstetric literature, there are only a handful of case reports dealing with the prenatal diagnosis of fibular hemimelia (FH; or longitudinal deficiency of the fibula or postaxial hypoplasia of the lower extremity) as an isolated finding or as part of a syndrome.2-9 Typically, it has been diagnosed at birth, when the neonate is seen to have lower limb shortening, a foot deformity (missing 1 or 2 of the lateral toes), or both. However, in the orthopedic literature, there are many case series dealing with the surgical treatment of this entity. We report a case of FH diagnosed prenatally during a routine anatomic survey.