Multiple epiphyseal dysplasia refers to a heterogeneous group of very rare congenital diseases characterized by epiphyseal anomalies. They can be divided into six different levels of expressivity (MED / EDM 1-6). MED lead to recurrent osteochondritis and early osteoarthritis in patients as a result of altered epiphyses.
Joint pain occurs at early age. The clinically best characterized form of EMD1 causes waddling in the patient with pain onset and moderate dwarfism. The most important complication is early hip osteoarthritis. About 50% of those affected show abnormalities prenatal or at birth, such as clubfeet or clinodactyly, while the painful symptoms occur in later childhood.
Inheritance is autosomal recessive or autosomal dominant, depending on the type. The most common autosomal dominant mutation is the COMP gene, which encodes the oligomeric matrix protein of cartilage and is located on chromosome 19 (19p13.1). Other affected genes are COL9A1, COL9A2, COL9A3 and MATN3, which encode the cartilage-specific collagen 9 and the matrilin-3 protein.
The less common recessive form of the disease is caused by mutations in the SLC26A2 (DTDST) gene. The diagnosis is based on clinical, radiological and molecular genetic analysis. With MRI examinations, it is possible to identify the arthrotic articular changes before they can be seen in an ordinary X-ray image. A causal therapy does not exist for patients of EDM.
Today's treatment consists mainly of physiotherapeutic and orthopedic measures. Frequently a hip replacement is required.