About Larsen Syndrome

Fast Facts

Definitions for words in orange can be found in the glossary

  • LS was first described as a syndrome in 1950 Dr. Loren J. Larsen and his associates in San Francisco, CA.
  • The description of LS was first published in The Journal of Pediatrics, Vol. 37, No 4, Pages 574-581, October, 1950:  “Multiple Congenital Dislocations Associated with Characteristic Facial Abnormality.”
  • LS is considered to be an inherited genetic condition and is classified as a skeletal dysplasia- an abnormal development of the skeletal system.
  • Congenital deformities most commonly seen in LS patients include dislocations of major joints including the elbows, hips, and knees.
  • FullSizeRender (2)

    Kenna,13, is happy to be at one of her favorite places-summer camp.

  • Common foot deformities may include club foot or equinovarus or equinovalgus deformities of the feet.
  • Hand deformities include long-cylindrical-shaped fingers and and a larger than average, rounded thumb referred to as spatulate.
  • Identifying facial features commonly include wide-spaced eyes, prominent forehead, and a depressed nasal bridge collectively described as flattened facies.
  • People with LS are usually short-statured- oftentimes below 5 feet tall- when full growth is reached.
  • LS can manifest in each patient differently, even among siblings or parents and their children.
  • Intellectual development is generally unaffected but there can be associated defects in the cardiovascucular, respiratory, and/or urogenital systems.  Spinal defects such as kyphosis and lordosis, sometimes severe, can also occur.
  • LS is believed to occur in 1 out of every 100,000 births, but incorrect diagnosis of similar conditions such as arthrogryposis )are thought to affect this estimate.

For a more complete description of LS, please refer to the  National Organization for Rare Disorders and this article written by Dr. John S. Graham