Epiphyseal Dysplasia, Multiple, 3, also known as multiple epiphyseal dysplasia 3, is related to multiple epiphyseal dysplasia and epiphyseal dysplasia, multiple, 2. An important gene associated with Epiphyseal Dysplasia, Multiple, 3 is COL9A3 (Collagen Type IX Alpha 3 Chain). Affiliated tissues include bone, and related phenotypes are knee pain and limited knee extension