Meyer dysplasia


A small, dense femoral epiphysis should always make you think of avascular necrosis (Perthes disease if idiopathic). However, where there is no change, and the femoral head as an apparent nodularity to the ossification, Meyer dysplasia is a good differential.

The nodularity of ossification is sometimes termed "morulated" which derives from cleavage and separation in embryology but is rarely used in clinical practice.