Larsen Syndrome

Larsen syndrome (LS), is a congenital disorder discovered in 1950 by Larsen and associates when they observed dislocation of the large joints and face anomalies in six of their patients. Patients suffering from Larsen syndrome normally present with a variety of symptoms including: congenital anterior dislocation of the knees, dislocation of the hips and elbows, flattened facial appearance, prominent foreheads, and depressed nasal bridges. Larsen syndrome can also cause a variety of cardiovascular anomalies and orthopedic abnormalities. This rare disorder is caused by a genetic defect in the gene encoding filamin B, a cytoplasmic protein that is important in regulating the structure and activity of the cytoskeleton. The gene that influences the emergence of Larsen syndrome is found in chromosome region, 3p21.1-14.1, a region containing Human type VII collagen gene. Larsen syndrome has recently been described as a mesenchyme disorder that affects the connective tissue of an individual. Autosomal dominant and recessive forms of the disorder have been reported, although most cases are autosomal dominant. Reports have found that in Western societies, Larsen syndrome can be found in 1 in every 100,000 births, however, this is most likely an underestimate because the disorder is frequently unrecognized or diagnosed as another disorder.