Fibular hemimelia, also known as congenital absence of the fibula, congenital deficiency of the fibula, paraxial fibular hemimelia, and aplasia or hypoplasia of the fibula, is the most common long bone deficiency

Some have recently postulated that interference with limb-bud development plays an important role in postaxial hypoplasia of the lower extremity.

During the fetal period, the fibular field of the limb bud controls development of the proximal femur, explaining the frequent association of femoral abnormalities

Involved limb is usually shortened, and the foot is in equinovalgus position

Classically the skin has dimpling seen over the tibia

Clinically, primary problems related to fibular hemimelia are limb length inequality and foot/ankle instability

Proximal femoral focal deficiency (PFFD) Coxa vara Femoral hypoplasia with external rotation Lateral patella subluxation Hypoplastic lateral femoral condyle Genu valgus with lateral mechanical axis

displacement

Flattened tibial eminence with absent cruciate and a positive Lachman sign

Short and/or bowed tibia Equino valgus at ankle Ball-and-socket ankle Absent tarsal bones Tarsal coalitions Absent foot rays

Type 1 deformity -hypoplasia of the fibula Type 1A- The proximal fibular epiphysis is

distal to the proximal tibial epiphysis and the distal fibular epiphysis is proximal to the talar dome.

Type 1B- The deficiency of the fibula is more severe, with 30% to 50% of the length missing and no distal support for the ankle joint

Type 2 deformity -Complete absence of the fibula.

The goals of treatment are equalization of limb length and correction of the foot deformity

Conservative management- No

treatment or the use of heel lifts may be adequate, particularly in discrepancies less than 2 cm

Epiphysiodesis of the normal leg is performed at the appropriate time so that leg lengths are equal at the end of skeletal growth

Gruca procedure- Rarely is indicated and should be used only when the foot is to be salvaged and the ankle requires stabilization.

Syme’s Amputation and prosthetic rehabilitation- When limb-length discrepancy is predicted to be more than 12 to 15 cm and the foot is deformed.

The advantages of early amputation include fewer hospitalizations and surgical procedures. Children who undergo amputation at an early age show excellent emotional adaptation to their disability and have good functional results

Both posterior and lateral releases are required.

The tendo calcaneus, as well as the fibrocartilaginous anlage of the absent fibula, must be released

Ankle valgus can be corrected with a dome or varus supramalleolar osteotomy