Almost all of the conditions that effect the bones and joints of people with Down syndrome arise from the abnormal collagen found in Down syndrome. One of the types of collagen (type VI) is encoded by a gene found on the 21st chromosome. The resulting effect in people with DS is increased laxity, or looseness, of the ligaments that attach bone to bone and muscle to bone. The combination of this ligamentous laxity and low muscle tone contribute to orthopedic problems in people with Down syndrome.
Five to eight percent of children with DS will develop abnormalities of the hip. The most common condition is dislocation of the hip, which is also called subluxation. In this condition, the head of the thigh bone (the femur) moves out of the socket formed by the pelvis (the acetabulum). This dislocation may or may not be associated with malformation of the acetabulum. Interestingly, hip subluxation in children with Down syndrome is hardly ever found at birth but instead is most common between the ages of 3 and 13 years. This medical information gave me the idea to make a video about two sisters, the eldest is a well known ballet dancer in Austria and abroad. Her little sister was born with DS. The intense care of the family to deal with her disability from childhood on, gave her the chance to learn ballet dancing and brought her to perform with a group of ballet dancers in the Opera House of Vienna. The overlapping shots are done with an Omani young man with Down Syndrome. Per year around 100 DS children are born in Oman because in Islamic culture abortion is forbidden. The young man is very close to his family and included in the daily live of the neighbourhood. His restricted mobility, like you can see in the video, is typical for DS. The famous geneticist from Oman Dr. Anna Rajab speaks about the social and medical aspects of the non genetic disease: Down Syndrome.