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Disease Profile

Familial osteochondritis dissecans

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset






Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Osteochondritis dissecans, short stature, and early-onset osteoarthritis


Congenital and Genetic Diseases; Musculoskeletal Diseases


Osteochondritis dissecans is a joint condition that occurs when a piece of cartilage and the thin layer of bone beneath it, separates from the end of the bone. If the piece of cartilage and bone remain close to where they detached, they may not cause any symptoms. However, affected people may experience pain, weakness and/or decreased range of motion in the affected joint if the cartilage and bone travel into the joint space. Although osteochondritis dissecans can affect people of all ages, it is most commonly diagnosed in people between the ages of 10 and 20 years.[1][2] In most cases, the exact underlying cause is unknown. Rarely, the condition can affect more than one family member (called familial osteochondritis dissecans); in these cases, osteochondritis dissecans is caused by changes (mutations) in the ACAN gene and is inherited in an autosomal dominant manner.[3] Treatment for the condition varies depending on many factors, including the age of the affected person and the severity of the symptoms, but may include rest; casting or splinting; surgery and/or physical therapy.[2][4]


The signs and symptoms of osteochondritis dissecans vary from person to person. If the piece of cartilage and bone remain close to where they detached, they may not cause any symptoms. However, affected people may experience the following if the cartilage and bone travel into the joint space:[1][2][4]

  • Pain, swelling and/or tenderness
  • Joint popping
  • Joint weakness
  • Decreased range of motion

Although osteochondritis dissecans can develop in any joint of the body, the knee, ankle and elbow are most commonly affected. Most people only develop the condition in a single joint.[2]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
1%-4% of people have these symptoms
Short fingers or toes
Broad hallux
Broad big toe
Wide big toe

[ more ]

Depressed nasal bridge
Depressed bridge of nose
Flat bridge of nose
Flat nasal bridge
Flat, nasal bridge
Flattened nasal bridge
Low nasal bridge
Low nasal root

[ more ]

Lumbar hyperlordosis
Excessive inward curvature of lower spine
Midface retrusion
Decreased size of midface
Midface deficiency
Underdevelopment of midface

[ more ]

Short thumb
Short thumbs
Small thumbs

[ more ]

Percent of people who have these symptoms is not available through HPO
Accelerated skeletal maturation
Advanced bone age
Early bone maturation

[ more ]

Autosomal dominant inheritance
Formation of new noncancerous bone on top of existing bone
Frontal bossing
Growth abnormality
Abnormal growth
Growth issue

[ more ]

Hip osteoarthritis
Degenerative joint disease
Osteochondritis Dissecans
Short stature
Decreased body height
Small stature

[ more ]

Waddling gait
'Waddling' gait
Waddling walk

[ more ]



In most cases, the exact underlying cause of osteochondritis dissecans is not completely understood. Scientists suspect that it may be due to decreased blood flow to the end of the affected bone, which may occur when repetitive episodes of minor injury and/or stress damage a bone overtime.[4]

In some families, osteochondritis dissecans is caused by changes (mutations) in the ACAN gene. In these cases, which are referred to as familial osteochondritis dissecans, the condition generally affects multiple joints and is also associated with short stature and early-onset osteoarthritis. The ACAN gene encodes a protein that is important to the structure of cartilage. Mutations in this gene weaken cartilage, which leads to the various signs and symptoms of familial osteochondritis disssecans.[3]


A diagnosis of osteochondritis dissecans is usually suspected based on the presence of characteristic signs and symptoms. Additional testing can then be ordered to confirm the diagnosis. These test may include x-rays, magnetic resonance imaging (MRI) and/or computed tomography (CT scan).[1][2]

For more information about the diagnosis of osteochondritis dissecans, please click here.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.


The primary aim of treatment for osteochondritis dissecans is to restore normal function of the affected joint, relieve pain and prevent osteoarthritis. Treatment for the condition varies depending on many factors including the age of the affected person and the severity of the symptoms. In children and young teens, osteochondritis dissecans often heals overtime without surgical treatment. These cases are often managed with rest and in some cases, crutches and/or splinting to relieve pain and swelling.[1][2][4]

If non-surgical treatments are not successful or the case is particularly severe (i.e. the cartilage and bone are moving around within the joint space), surgery may be recommended. Following surgery, physical therapy is often necessary to improve the strength and range of motion of the affected joint.[1][2][4]

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • FamilyDoctor.org provides additional information about Familial osteochondritis dissecans. Click on the link above to access this information.
  • The Mayo Clinic Web site provides further information on Familial osteochondritis dissecans.
  • Genetics Home Reference (GHR) contains information on Familial osteochondritis dissecans. This website is maintained by the National Library of Medicine.
  • The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) support research into the causes, treatment, and prevention of arthritis and musculoskeletal and skin diseases, the training of basic and clinical scientists to carry out this research, and the dissemination of information on research progress in these diseases. Click on the link to view information on this topic.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Familial osteochondritis dissecans. Click on the link to view a sample search on this topic.


  1. Osteochondritis dissecans. Mayo Clinic. September 2012; https://www.mayoclinic.org/diseases-conditions/osteochondritis-dissecans/basics/symptoms/con-20024803.
  2. Osteochondritis Dissecans. American Academy of Orthopaedic Surgeons. March 2012; https://orthoinfo.aaos.org/topic.cfm?topic=A00610.
  3. Familial osteochondritis dissecans. Genetics Home Reference. October 2012; https://ghr.nlm.nih.gov/condition/familial-osteochondritis-dissecans.
  4. Grant Cooper, MD. Osteochondritis Dissecans. Medscape Reference. May 2014; https://emedicine.medscape.com/article/1253074-overview#a0112.

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