Meyahealth
HomeGeneticsConditionMultiple epiphyseal dysplasia
Back to Condition
Multiple epiphyseal dysplasia
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Condition

Multiple epiphyseal dysplasia

Multiple epiphyseal dysplasia is a disorder of cartilage and bone development that primarily affects the ends of the long bones in the arms and legs, often leading to joint pain and early-onset arthritis.

Overview

Multiple epiphyseal dysplasia (MED) affects the development of the epiphyses—the ends of the long bones. There are two main types of the disorder, distinguished by their inheritance patterns. Both types generally present with mild symptoms, including joint pain (most commonly in the hips and knees), early-onset arthritis, and a waddling walk. While some individuals may experience mild short stature, most reach a normal adult height. Diagnosis usually occurs during childhood, though mild cases may not be identified until adulthood.

The recessive form of the disorder is distinguished by additional malformations, including abnormal curvature of the spine and issues with the hands, feet, and knees. Approximately 50 percent of individuals with the recessive form are born with physical abnormalities such as clubfoot, cleft palate, unusual finger or toe curvature, ear swelling, or a double-layered kneecap (patella).

Frequency

The incidence of dominant MED is estimated at at least 1 in 10,000 newborns. The incidence of the recessive form is unknown. Both forms may be more common than reported, as mild cases often go undiagnosed.

Causes

Dominant MED is caused by mutations in the COMP, COL9A1, COL9A2, COL9A3, or MATN3 genes. These genes produce proteins essential for cartilage and bone formation. Mutations in COMP or MATN3 prevent these proteins from being released into the spaces between cartilage-forming cells (chondrocytes), leading to abnormal cartilage development. Mutations in the type IX collagen genes (COL9A1, COL9A2, COL9A3) are less common and may cause the protein to accumulate inside cells or interact abnormally with other cartilage components.

Recessive MED is caused by mutations in the SLC26A2 gene. This gene provides instructions for a protein essential for normal cartilage development and its conversion into bone. Mutations here alter the structure of developing cartilage, preventing proper bone formation.

Inheritance

  • Autosomal dominant: One copy of the altered gene is sufficient to cause the disorder. This can be inherited from an affected parent or result from a new mutation in the gene.
  • Autosomal recessive: Both copies of the gene in each cell must have mutations. Parents of an affected individual typically each carry one copy of the mutated gene but do not show symptoms.

Frequently Asked Questions

Physical therapy focused on low‑impact strengthening (e.g., swimming, cycling) and range‑of‑motion exercises can reduce pain. NSAIDs or acetaminophen are used for breakthrough discomfort. Orthotic shoes or custom knee braces improve alignment, and early referral to a rheumatologist for disease‑modifying strategies (e.g., intra‑articular hyaluronic acid injections) may delay arthritic changes.
Look for painless or mildly painful swelling of the knees, hips, or ankles during early walking, a waddling gait, or delayed motor milestones. Recurrent joint pain after activity, especially in the hips or knees, and a family history of similar joint issues are red flags that merit a pediatric orthopedic evaluation.
Initial diagnosis relies on plain X‑rays showing irregular, delayed ossification of the epiphyses, often with flattened or fragmented ends. If radiographs are suggestive, a targeted genetic panel for COMP, MATN3, and COL9A1‑A3 genes is ordered; a positive pathogenic variant confirms the diagnosis and clarifies dominant versus recessive inheritance.
Clubfoot is treated promptly with the Ponseti casting method, followed by bracing; cleft palate requires surgical repair and speech therapy. A double‑layered patella often benefits from physiotherapy to strengthen quadriceps and may need surgical realignment if instability persists. Lifelong orthopedic surveillance—annual clinical exams and periodic X‑rays—helps catch early joint degeneration and guides timely interventions.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

Meyahealth

Ⓒ 2026. All rights reserved by MEYA

About UsTerms & PolicyFAQ