Postaxial hypoplasia of the lower extremity

Congenital deficiency of the fibula may present a variety of patterns. In a series of 20 patients with this diagnosis, we have observed limb-length in equality and a spectrum of musculoskeletal anomalies involving the ipsilate ral hip, femur, knee, tibia/fibula. ankle, and foot. Considering the freque ntly associated abnormalities of the lower extremity, the term post axial h ypoplasia may be more descriptive than the traditional terms fibular hemime lia or fibular a/hypoplasia. By raising the awareness of associated deformi ties, the clinician is better prepared to advise patients and to intercede accordingly. Based on our experience, we advocate a modular treatment appro ach combining limb lengthening with hemiepiphysiodesis of the distal femur and/or ankle to corner valgus alignment and establish a neutral mechanical axis. Contralateral epiphysiodesis as an adjunct may be preferable to doubl e or repeated lengthening. The goal is to achieve symmetry and stable joint s at skeletal maturity with a minimal number of well-timed surgical interve ntions. By using this strategy and with minimal morbidity, 10 of our patien ts who have reached skeletal maturity have achieved a satisfactory outcome.