Purpose: To determine the various musculoskeletal manifestations of multiple epiphyseal dysplasia in children, and the course of this disease in childhood. Methods: Ten children were diagnosed and treated at the Children's Hospital of Eastern Ontario (CHEO) for multiple epiphyseal dysplasia, 1976-2001. We reviewed the clinical, pathological and radiographic records for these cases to determine cause of presentation and progress of the musculoskeletal pathology during the course of this disease in this age group. Results: Average age at time of first presentation was 6 years and 4 months (range 2 wk to 13 yr). Mean follow-up was 6 years and 2 months (range 1-144 mo). Only 2 children required surgery. Two children were diagnosed at birth; 2 were referred as cases of bilateral Legg-Calv� -Perthes disease. Two children presented with asymmetrical genu valgum; 1 with knee pain, genu valgum, loose bodies, and early degenerative joint disease of both knees; and 2 with limp. Conclusion: Although multiple epiphyseal dysplasia is a disease of childhood, it is seldom severe enough to require operative intervention in the initial 2 decades of life.
Objet : D�terminer les diverses manifestations musculosquelettiques de la dysplasie �piphysaire multiple chez les enfants et l'�volution de cette maladie au cours de l'enfance. M�thodes : On a diagnostiqu� une dysplasie �piphysaire multiple chez 10 enfants trait�s au Centre hospitalier pour enfants de l'Est de l'Ontario de 1976 � 2001. Nous avons �tudi� les dossiers cliniques, pathologiques et radiologiques de ces patients pour d�terminer la cause de la pr�sentation et l'�valuation de la pathologie musculosquelettique pendant l'�volution de cette maladie chez les sujets de ce groupe d'�ge. R�sultats : Au moment de la premi�re pr�sentation, les sujets avaient en moyenne 6 ans et 4 mois (intervalle de 2 semaines � 13 ans). Le suivi moyen s'est �tabli � 6 ans et 2 mois (intervalle de 1 � 144 mois). Deux enfants seulement ont d� subir une intervention chirurgicale. On a diagnostiqu� la maladie chez deux enfants � la naissance, deux ont �t� r�f�r�s comme cas de maladie de Legg-Perthes-Calv�. Deux enfants se sont pr�sent�s avec un genou cagneux asym�trique; un avait de la douleur au genou, le genou cagneux, des corps flottants et une arthrose d�g�n�rative pr�coce des deux genoux; deux autres boitaient. Conclusion : M�me si la dysplasie �piphysaire multiple est une maladie infantile, elle est rarement assez grave pour exiger une intervention chirurgicale au cours des deux premi�res d�cennies de la vie.
Multiple epiphyseal dysplasia (MED) is a genetic dysfunction with an autosomal dominant inheritance pattern causing an altered enchondral ossification affecting epiphyseal ossification centres.1-5 The weight-bearing joints are most affected, and severity appears to grade from mild through severe forms. The articular cartilage, although initially normal, becomes secondarily misshapen because of underlying bone deformities, resulting in early degenerative arthritis.6-10 It is often confused with Legg-Calv�-Perthes disease (LCP) when the hips are the primary joints involved. Treatment of MED in a manner similar to LCP with prolonged abduction is not required and subjects the child to unwarranted therapeutic morbidity. To determine the early musculoskeletal manifestations of MED in children and the course of this disease in childhood as well as to compare its diagnostic features to LCP, we undertook a retrospective review of all cases at a major pediatric referral centre over a period of 25 years.
Materials and methods
Review of all the relevant clinical, pathological and radiographic records at a major pediatric centre revealed 10 children treated for MED since 1985: 8 boys and 2 girls. Average age at initial presentation was 6 years and 4 months, with a range of 2 weeks to 13 years (Table 1). Four patients had a positive family history for musculoskeletal dysplasia. Two children (cases 1 and 8) had a family history of MED: patient 2 came from a family short-statured due to musculoskeletal dysplasia; patient 3 had a father with osteochondrodysplasia (Fig. 1). Two presented at birth: patient 1 with congenital feet deformity (metatarsus varus) treated by corrective casts, and patient 4 with extensive punctate calcification of his bones, discovered at birth via chest radiographs. Two patients (cases 7 and 9) were referred as having bilateral LCP at the ages of 10 and 3 years (Fig. 2). Two patients (cases 2 and 6) exhibited bilateral asymmetrical genu valgum (Fig. 3). One patient (case 3) presented with knee pain, genu valgum, loose bodies and early degenerative joint disease of both knees (Fig. 4). Two padents (cases 3 and 5) arrived with a limp only (Table 1). Four cases had associated congenital anomalies: patient 4 had hypospadius and hemangioma in the left medial canthal area; patient 7 had a nasal septal defect; and patients 1 and 8 had bilateral metatarsus varus.
Radiographic findings
Radiographs of all the children were reviewed. Hips were the initial joints identified with MED in all children (Fig. 2). Appearance of the secondary centre of ossification of the femoral head was usually delayed, to a maximal age in this series of 2 years and 6 months. Radiographic femoral head irregularities often appeared by 12 months of age. Epiphyseal fragmentation of the femoral head was always evident by the age of 10 years. Flattening and loss of height of the femoral heads occurred in all 10 patients, with associated femoral neck shortening, widening and varus deformity by skeletal maturity (Fig. 5). In all cases the acetabulum was well formed and minimally involved, with minor irregularities and dysplasia seen with late ossification. MED in the hips was well contained in all the children. Knees were the second most frequently affected joints.11-13 Distal femoral and proximal tibial epiphyses showed losses of height and irregularities. The knees all exhibited mild to severe valgus. Loose osteochrondral bodies and early degenerative joint disease was evident in 1 child, patient 3 (Fig. 4).
Bilateral hemiepiphysiodesis of the medial distal femoral epiphyses due to increasing genu valgum of both knees was required in 1 child, patient 2 (Fig. 3). No other reconstructive surgery has been necessary to date. One child, patient 10, arrived with a fractured femur caused by trauma; his MED was noted incidentally.
Discussion
Although MED is a disease of childhood that presents with various clinically notable pathologies, such as short stature, limp, angular deformities, abnormal gait and occasional pain, it seldom requires early surgical management. Confusion with bilateral LCP may occur in these children, leading to overtreatment with abduction orthosis or innominate osteotomy. To avoid this misdiagnosis and overtreatment, the typical radiological criteria for MED has been compared with LCP in Table 2. It is also recommended that all patients with suspected bilateral LCP have a detailed family history recorded, as well as radiographs of their knees and ankles to detect MED.
Supportive measures, corrective osteotomies or epiphysiodesis may occasionally be required for varus or valgus deformity of the knee. Serious disability due to MED occurs late in the third or fourth decade of life, mainly associated with degenerative arthritis and requiring total joint replacement of the hips or knees.14,15 Education of the child with MED and his or her family about the expected course of the disease is important, to influence occupational choices and promote joint preservation.
Although every effort was made in this review to ensure the identification of all families of children who have MED, including a review of the medical records and the Department of Genetics' patient statistics concerning MED, there were probably some patients not identified as having MED who have very mild involvement of their joints. The low percentage of involvement by other family members (40%) was undoubtedly due to the condition being a minor affliction in some members and a major disability in others. Since we did not examine every family member, some were undoubtedly missed. Multiple epiphyseal dysplasia is a spectrum of joint incongruity from mild to severe, and, as in most chronic disease processes, it is to the family's advantage to understand the treatment options and how to minimize joint stresses in both activities of daily living and occupational needs.
Competing interests: None declared.
[Reference]
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[Author Affiliation]
Salem Bajuifer, MD; Merv Letts, MD
[Author Affiliation]
Division of Pediatric Orthop�dics, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Ont.
Accepted for publication Jan. 7, 2004
Correspondence to: Dr. Merv Letts, Department of Surgery, Shaikh Khalifa Medical Centre, PO Box 51900, Abu Dhabi, UAE; fax 971 2 610 4962; letmer764@skmc.gov.ae
