Congenital radio-ulnar synostosis
Type of disease: Rare conditions
Congenital radio-ulnar synostosis is a rare condition in which there is an abnormal connection (synostosis) of the radius and ulna (bones in the forearm) at birth. The condition is present in both arms (bilateral) in approximately 60% of cases. Signs and symptoms depend on the severity of the abnormality and whether it is bilateral; affected individuals often have limited rotational movement of the forearm. Pain is usually not present until the teenage years. It is due to abnormal fetal development of the forearm bones, but the underlying cause is not always known. It is sometimes a feature of certain chromosome abnormalities or genetic syndromes. Some cases appear to be inherited in an autosomal dominant manner. Treatment may be conservative or involve surgery depending on the severity of the abnormality and the range of movement. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.