Fibular hemimelia

Lore & Background

Fibular hemimelia presents at birth as a shortening or complete lack of the fibula, often accompanied by a fibrous band instead of the bone. The condition causes a short, deformed leg, absence of the lateral part of the ankle joint, and an unstable equinovalgus foot deformity. Partial or total absence of the fibula is among the most frequent limb anomalies and is the most common skeletal deformity in the leg. It may also involve absence or fusion of toes, and in severe forms, limited ankle motion and stability.

Reader's Guide

Fibular hemimelia is significant as the most common long bone deficiency and a leading cause of congenital leg deformity. The cause remains unclear, with possible factors including maternal viral infections, embryonic trauma, teratogenic exposures, or vascular dysgenesis between four and seven weeks gestation. Treatment decisions are often made prenatally via ultrasound, with options including amputation at around six months to prepare for prosthetic use, or repeated corrective osteotomies and leg-lengthening using the Ilizarov apparatus—though these are costly and associated with residual deformity. The condition has affected notable Paralympic athletes and public figures, highlighting its impact on mobility and adaptation.

Did You Know?

• Fibular hemimelia is the most common congenital absence of a long bone of the extremities.
• The disorder can be noted by ultrasound in utero to prepare for amputation after birth or complex bone-lengthening surgery.
• Males are affected twice as often as females in most series.
• Possible causes include maternal viral infections, embryonic trauma, teratogenic environmental exposures, or vascular dysgenesis between four and seven weeks gestation.