MULTIPLE EPIPHYSEAL DYSPLASIA

Peter J. Curcione, D.O., Resident, Orthopaedic Surgery

Robert P. Stanton, M.D., Attending, Pediatric Orthopaedic Surgery

August 17, 1995

CLINICAL CASE PRESENTATION

ORTHOPAEDIC DEPARTMENT

THE ALFRED I. DUPONT INSTITUTE

WILMINGTON, DELAWARE

Etiology/History:

• .First described by Fairbanks in 1937
• One of the osteochondrodysplasias. Inherited disorder, that is predominantly autosomal dominant.
• Characterized by abnormal enchondral ossification of multiple physes and epiphyses of tubular bones.
• Thought to be due to a genetic mutation on chromosome 19 resulting in imperfect articular cartilage unable to withstand normal cyclic loading.
• Commonly begins with painful or stiff lower extremities.
• Joints are most commonly affected symmetrically. The hip and knee joints are most frequently affected.
• Irregular epiphyseal and physeal growth, skeletal deformities (coxa vara, genu valgum or varum), short limb dwarfism and short stubby hands and feet.
• Can present similar to bilateral Perthes' disease. Must also be differentiated from hypothyroidism, spondyloepiphyseal dysplasia and pseudoachondroplastic dysplasia.
• Two forms have historically been described: 1. Ribbing form, milder, with flat epiphyses and minimal involvement of the hands and feet. 2. Fairbank form, more severe form, with late appearing epiphyses and greater involvement of the hands and feet.

Clinical and Radiographic:

• Lower extremity joint pain and stiffness, short stature, short stubby hands and feet along with a waddling gait are features of MED.
• Patients have normal intelligence.
• Adult height usually range from 145 to170cm.
• Limb epiphyses show delayed appearing centers of ossification, often demonstrating a fragmented appearence. Joint involvement is usually symmetric.
• Premature arthrosis of weight-bearing joints, most frequently the hips, due to delay in ossification of the capital femoral epiphysis. The cartilaginous femoral head model becomes misshapen and incongruous with time, leading to early arthritis.
• Early detection may be possible through family history. Also may done by radiographic means. Schlesinger outlined distal femoral epiphyseal and metaphyseal measurements. Poznanski outlined carpal and metacarpal measurements. Either may be abnormally low (greater than 2 S.D. below normal) in approx. 80% of cases.
• Schlesinger's work demonstrated that the epiphysis tends to be thinner in these patients
• Avascular necrosis (AVN) of the hip superimposed on M.E.D. has been reported to occur. These patients can present as Perthes'. Can document A.V.N. by serial radiographic changes superimposed on a dysplastic epiphysis or characteristic changes depicted on bone scan and MRI. Asymmetric changes will be noted on each study.
• Must differentiate M.E.D. from Perthes' disease. M.E.D. is usually symmetric, does not show the radiographic changes characteristic of Perthes' over time, not associated with metaphyseal cyst formation. and the acetabulum is often irregular unlike Perthes'.

Treatment:

Progressive disorder usually leading to osteoarthritis in weight-bearing joints by the second or third generation of life.

Patients should refrain from contact sports, high impact activities, (ie. jogging, running).

Weight control should be emphasized early on.

Patients tend to tire easily... they must rest more frequently.

Osteotomies about the knee can be done in order to correct alignment.

Varus osteotomy of the femur should be avoided, as these people tend to develop a varus deformity and incongruity as a result of this dysplasia.

If AVN is superimposed on M.E.D.. then stretching programs should be started . No data is yet available on results of surgical containment or bracing of hips.

Patients will most likely require joint replacement surgery in adulthood.

Bibliography:

1. Treble,N.J.,Jensen,F.O.,Bankier,A.,Rogers,J.G.,Cole,W,G. Development of the hip in Multiple Epiphyseal Dysplasia. J.B.J.S. 1990; 72-B: 1061-1064.

2. Mackenzie, W.G., Basset, G.S., Mandell, G.A., Scott, C.I. Avascular necrosis of the hip in Multiple Epiphyseal Dysplasia. J.P.O. 1990; 9: 666-671.

3. Schlesinger, A.E., Poznanski, A.K., Pudlowski, R.M., Millar, E.A. Distal femoral epiphysis: Normal standards for thickness and application to bone dysplasias. Radiology. 1986; 159: 515-519.

4. Poznanski, A.K., Hernandez, R.J., Guire, K.E., Bereza, U.L., Garn, S.M. Carpal length in children- A useful measurement in the diagnosis of rheumatoid arthritis and some congenital malformation syndromes. Radiology 1978; 129: 661-668.

5. Ingram, R.R. Early diagnosis of Multiple Epiphyseal Dysplasia. J.P.O. 1992; 12: 241-244.

6. Crossan,J.F. Bilateral failure of the capital femoral epiphysis: Bilateral Perthes' disease, Multiple Epiphyseal Dysplasia, Psuedoachondroplasia and Spondyloepiphyseal Dysplasia Congenita and Tarda. J.P.O. 1983; 3:297-301.

7. Stanescu, R., Stanescu, V., Muriel, M., Maroteaux, P. Multiple Epiphyseal Dysplasia, Fairbank Type: Morphologic and biochemical study of cartilage. Am. J. Med. Gen. 1993; 45: 501-507.

8. Deere,M., Blanton, S.H., Scott, C.I., Langer, L.O., Pauli, R.M., Hecht, J.T. Genetic heterogeneity in M.E.D. Am. J, Hum. Genet. 1995; 56:698-704.