Postaxial Hypoplasia of Lower Extremity (Fibular Hemimelia) Clinical Presentation

Updated: Aug 05, 2016
  • Author: Michael C Holmstrom, MD; Chief Editor: Thomas M DeBerardino, MD  more...
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Presentation

History and Physical Examination

Presentations of postaxial hypoplasia of the lower extremity (fibular hemimelia) vary widely, ranging from what appears to be merely an absent fifth toe in a newborn or a minimal difference in limb lengths to severe fibular deformities that are immediately apparent. [15]  The clinician must also look for associated abnormalities, including problems with alignment and stability, and must realize that the clinical picture may evolve with growth and development.

Clinical findings may include the following:

  • Fibular abnormality, ranging from minimal shortening to complete absence of the fibula (see the first and second images below)
  • Femoral hypoplasia with external rotation
  • Lateral patellar subluxation
  • Hypoplastic lateral femoral condyle
  • Genu valgus with lateral mechanical axis displacement
  • Flattened tibial eminence with absent cruciate and a positive Lachman sign
  • Short or  bowed tibia (see the third image below)
  • Ankle valgus
  • Ball-and-socket ankle (see the fourth image below)
  • Absent tarsal bones (see the fifth image below)
  • Absent foot rays
Type II fibular hemimelia (complete absence) in 4- Type II fibular hemimelia (complete absence) in 4-month-old girl. Note skin dimple in midtibial area and 2-ray foot. Image courtesy of Dennis P Grogan, MD.
Type II fibular hemimelia (complete absence) in 1- Type II fibular hemimelia (complete absence) in 1-year-old girl. Note that foot is in significant valgus position. Image courtesy of Dennis P Grogan, MD.
Type II fibular hemimelia and significant anterior Type II fibular hemimelia and significant anterior bowing of tibia in 9-month-old boy. Image courtesy of Dennis P Grogan, MD.
Fibular hemimelia. Ball-and-socket ankle joint is Fibular hemimelia. Ball-and-socket ankle joint is common finding in fibular hemimelia. In and of itself, it is usually not problematic, but it is commonly associated with limb-length discrepancy and tarsal coalition. Image courtesy of Dennis P Grogan, MD.
Fibular hemimelia in 4-month-old girl. Fibula is a Fibular hemimelia in 4-month-old girl. Fibula is absent, as is proximal tibial ossification center. Two metatarsals are associated with 3 phalanges, 2 of which are fused to form only 2 toes. Image courtesy of Dennis P Grogan, MD.