Multiple epiphyseal dysplasia

Clinical History

A seven-year-old boy, born with bilateral congenital talipes equino varus, persented for a follow-up after corrective surgery. A radiographic diagnosis of multiple epiphyseal dysplasia was made.

Imaging Findings

A seven-year-old boy was born with bilateral congenital talipes equino varus. In the follow-up exam following corrective surgery, he was found to be unable to make a proper fist with either hand. There was no flexion of the metacarpophalangeal joints and limited flexion of the interphalangeal joints. X-rays which were taken showed flattened epiphyses of all phalanges. Hip X-rays showed a similar appearance of the proximal femoral epiphyses together with femoral neck varus deformity.

Discussion

Multiple epiphyseal dysplasia (MED) is a condition characterized by the delay in the appearance of the epiphyses, flattened, fragmented symmetric epiphyseal formation, mild short stature and early-onset osteoarthritis. It is dominantly inherited. Mutations have been found in chromosome 19. The prevalence, as reported by a Danish study, is 9.0 per 100,000. MED can occur at various sites, e.g., the vertebral bodies, but the proximal femur is the most commonly affected and the condition can easily be confused with Perthes disease. The upper limbs are less involved and the formation of carpal ossification centres are delayed. MED is clinically and genetically heterogenous. 6 causative genes of MED have been reported. The diagnosis of MED can be made from the decreased plasma level of COMP (cartilage oligomeric matrix protein), a glycoprotein found around chondrocytes. Dominant MED was originally divided into Ribbing's dysplasia, which is a mild type, and Fairbank's dysplasia, which is a more severe type. However, much more clinical variability exists within the overall MED phenotype than is suggested by these two distinct entities. Individuals with MED resulting from COMP mutations have significant involvement at the capital femoral epiphyses and irregular acetabuli. Individuals with MED from MATN3 mutations have knee abnormalities that are similar to those in affected individuals with COL9A2 mutations. Both these are not as severe as in the COMP mutations. The pathology involves the development of the epiphyseal ossification centres. Endochondral ossification is disorganized and the epiphyseal cartilage cells are irregular. The articular cartilage is initially normal but becomes misshapen during the course of the patient's life because of the lack of an underlying osseous support. The articular deformities are permanent, with degenerative changes and osteoarthritis developing in early adult life. Diagnosis is not made until later in childhood. Affected children may complain of joint stiffness, pain, a limp or may have a waddling gait. The child has minimal short stature, stubby fingers and toes. There may be a flexion contracture of the elbows or the knees. Intelligence is not affected. The differential diagnosis includes Perthes disease, mild spondyloepiphyseal dysplasia and pseudoachondroplasia. Rarely is surgery needed in early childhood. Osteotomies are helpful in correcting the angular deformities. Total joint replacement may be needed in the patients whose hips are severely affected with osteoarthritis.

Differential Diagnosis List

Final Diagnosis

Multiple epiphyseal dysplasia.

URL:	https://eurorad.org/case/2906
DOI:	10.1594/EURORAD/CASE.2906
ISSN:	1563-4086