What is the management and treatment approach for a pediatric or young adult patient with multiple epiphyseal dysplasia, a genetic disorder affecting bone and cartilage development?

Management and Treatment of Multiple Epiphyseal Dysplasia

Multiple epiphyseal dysplasia requires early orthopedic surveillance with physical therapy referral, weight management to prevent obesity-related joint complications, and surgical intervention for progressive hip deformity or symptomatic loose bodies, with genetic testing essential for definitive diagnosis and family counseling. 1, 2

Diagnostic Confirmation

• Genetic testing should be performed in all suspected cases to confirm diagnosis and guide prognosis, as genotype-phenotype correlations are significant 1, 2
• COMP gene variants (58% of cases) cause the most severe phenotype with higher surgical intervention rates, while MATN3, COL9A2, COL9A1, COL9A3, CANT1, and SLC26A2 variants present with variable severity 1, 2
• Radiographic findings show flat, small, and irregularly shaped epiphyses, particularly affecting hips and knees, which can be mistaken for Perthes disease 1
• A comprehensive skeletal survey is mandatory to assess the extent of epiphyseal involvement across multiple joints 1

Weight Management (Critical Priority)

• Maintaining healthy weight is essential, as 73-77% of patients with multiple epiphyseal dysplasia are above average weight, which accelerates joint degeneration 3
• Obesity significantly worsens mobility outcomes and increases the need for joint replacement surgery 3
• Reduced physical activity due to joint pain creates a vicious cycle of weight gain and further joint deterioration 3

Physical Therapy and Mobility Support

• Early physical therapy referral is recommended to optimize joint function, strengthen periarticular muscles, and maintain range of motion 1
• Gait training and assistive devices may be needed for patients with waddling gait or joint deformities 1
• Activity modification to avoid high-impact sports while maintaining low-impact cardiovascular fitness is crucial 3

Orthopedic Surgical Management

Hip Deformity (Most Common Surgical Need)

• Intertrochanteric extension osteotomy provides good mid-term outcomes for severe coxa vara deformity, with satisfactory correction and improved joint function 4
• Trochanter arthroplasty combined with Dega osteotomy effectively addresses severe hip deformity with complete acetabular coverage of the femoral head 4
• Staheli acetabular augmentation can be considered for acetabular dysplasia 4
• Surgical intervention timing should occur before severe joint destruction develops, typically during childhood or adolescence 4

Loose Body Removal

• Arthroscopic removal of intra-articular loose bodies is highly effective for joint locking symptoms, which occur frequently in adult patients 5
• Free articular bodies causing mechanical symptoms require prompt surgical removal to prevent further cartilage damage 6, 5
• Knee, ankle, and elbow joints are commonly affected by loose bodies 6, 5

Joint Replacement

• Total joint arthroplasty (hip or knee) provides excellent outcomes in adults with end-stage degenerative joint disease 2
• Early-onset osteoarthritis typically develops in the third to fourth decade, necessitating joint replacement consideration 1, 2
• Patients with COMP variants (52% of cases) have higher rates of orthopedic surgery requirements 1

Surveillance Protocol

• Annual physical examination starting from diagnosis to monitor joint pain, range of motion, and functional limitations 1
• Serial radiographs every 2-3 years during growth to assess progression of epiphyseal irregularity and joint space narrowing 4
• Monitor for development of scoliosis, limb length discrepancy, and angular deformities requiring corrective osteotomy 2
• Screen for myopathy findings, as some patients present with muscle weakness mimicking neuromuscular disorders 1

Pain Management

• NSAIDs for symptomatic joint pain, with caution regarding long-term use in young patients 1
• Physical modalities including heat, ice, and therapeutic exercises to manage chronic pain 1
• Intra-articular corticosteroid injections may provide temporary relief but do not alter disease progression 2

Genetic Counseling

• Family screening is essential, as inheritance is typically autosomal dominant with high penetrance 1, 2
• Presymptomatic children of affected parents should undergo genetic testing and baseline radiographic evaluation 6
• Autosomal recessive SLC26A2 variants require different counseling regarding recurrence risk 2

Long-term Monitoring

• Lifelong orthopedic follow-up is required due to progressive nature of joint degeneration 4, 2
• Average follow-up of 7.2 years post-surgery shows maintained functional improvement, but longer surveillance is needed 4
• Patients should be counseled that despite optimal management, most will develop early osteoarthritis requiring joint replacement by middle age 1, 2

Critical Pitfalls to Avoid

• Do not dismiss joint pain in children as "growing pains" when radiographs show epiphyseal irregularities—this delays diagnosis and appropriate management 1
• Do not confuse MED with Perthes disease; MED affects multiple joints bilaterally and symmetrically, while Perthes is typically unilateral 1
• Do not delay genetic testing, as it confirms diagnosis, guides prognosis based on specific gene variant, and enables family screening 1, 2
• Do not overlook weight management counseling, as obesity dramatically worsens outcomes and accelerates need for joint replacement 3