Question: What are the symptoms of Familial osteochondritis dissecans ?
Answer: What are the signs and symptoms of Familial osteochondritis dissecans? 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: 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. The Human Phenotype Ontology provides the following list of signs and symptoms for Familial osteochondritis dissecans. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Autosomal dominant inheritance - Exostoses - Growth abnormality - Osteoarthritis - Osteochondrosis dissecans - Short stature - Waddling gait - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: What causes Familial osteochondritis dissecans ?
Answer: What causes osteochondritis dissecans? 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. 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.
Source: GARD

Question: How to diagnose Familial osteochondritis dissecans ?
Answer: How is osteochondritis dissecans diagnosed? 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). For more information about the diagnosis of osteochondritis dissecans, please click here.
Source: GARD