Intermediate ray deficiency—a new type of lower limb hypoplasia

Objective Diagnosis of fibular hemimelia is based on the identification of absence or shortening of the fibula in relation to the tibia. Despite the existence of different classifications of this congenital deficiency, certain morphological forms defy proper classification. One such form is absence of foot rays with leg shortening in the presence of an entire fibula. In these cases, foot morphology suggests that central foot rays, not lateral ones, are affected by the deficiency; thus justifying the hypothesis concerning the existence of a separate type of hypoplasia, which may be named “intermediate ray deficiency” (IRD).