Marfan syndrome is a set of inherited signs and symptoms, also associated with hypermobility of the joints, including the knee.
Patients tend to be tall and thin with very long thin fingers, and hypermobile joints. There may be problems in many organ systems, but in the knee the issues involve patella subluxation and dislocations and cruciate ligament problems.
Because the gene for Marfan's syndrome is dominant, parents with the disorder have a 50% chance of passing the condition on to their children.
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