Ankylosing spondylitis facts Ankylosing spondylitis belongs to a group of arthritis conditions that tend to cause chronic inflammation of the spine (spondyloarthropathies). Ankylosing spondylitis affects males two to three...

Polymyalgia rheumatica is a rare inflammatory disease characterized by muscle pain (myalgia), stiffness, and additional generalized systemic symptoms such as fatigue, low-grade fever, and/or a general feeling of ill health (malaise). Polymyalgia r...

Campomelic dysplasia is a severe disorder that affects the development of the skeleton and reproductive system. This condition is often life-threatening in the newborn period. The term "campomelic" comes from the Greek words for "bent limb." Affec...

Campomelic syndrome is a rare congenital disorder in which multiple anomalies are present. It is characterized by bowing and angular shape of the long bones of the legs, especially the tibia; multiple minor anomalies of the face; cleft palate; oth...

An epidemic is defined as occurring when "new cases of a certain disease, in a given human population during a given time period, substantially exceed what is expected based upon recent experience." Pediatric obesity has reached epidemic proportio...

De Barsy syndrome is a rare, autosomal recessive genetic disorder, the main characteristics of which are a prematurely aged-looking face (progeria), cloudy corneas, short stature, and mental retardation. The condition is expressed in variable pres...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Dysplasia epiphysealis hemimelica, also known as Trevor disease, is a rare skeletal developmental disorder of childhood. It is characterized by an overgrowth of cartilage on the ends (epiphyses) of the long bones of the arms and legs and the bones...

Facioscapulohumeral muscular dystrophy (FSHD), also known as Landouzy-Dejerine muscular dystrophy, is a neuromuscular disorder. Symptom onset usually occurs in adolescence or early adulthood; however, less commonly, symptoms may become apparent as...

Congenital fiber type disproportion (CFTD) is a rare genetic muscle disease that is usually apparent at birth (congenital myopathy). It belongs to a group of muscle conditions called the congenital myopathies that tend to affect people in a simila...

You have flatfeet when the arches on the inside of your feet are flattened, allowing the entire soles of your feet to touch the floor when you stand up. A common and usually painless condition, flatfeet can occur when the arches don't deve...

Langerhans cell histiocytosis (LCH) is a spectrum of rare disorders characterized by overproduction (proliferation) and accumulation of a specific type of white blood cell (histiocyte) in the various tissues and organs of the body (lesions). The l...

Hypermobility syndrome facts The joint hypermobility syndrome is a condition that features joints that easily move beyond the normal range expected for a particular joint. Hypermobile joints tend to be inherited. ...

Osteonecrosis, also known as avascular necrosis, is a disease resulting from the temporary or permanent loss of the blood supply to the bones. Without blood, the bone tissue dies and causes the bone to collapse. If the process involves the bones n...

Legg-Calvé-Perthes Disease (LCPD) is one of a group of disorders known as the Osteochondroses. The Osteochondroses typically are characterized by degeneration (avascular necrosis) and subsequent regeneration of the growing end of a bone (ep...

Osteogenesis Imperfecta (OI) is a group of rare disorders affecting the connective tissue and characterized by extremely fragile bones that break or fracture easily (brittle bones), often without apparent cause. The specific symptoms and physical ...

Marfan syndrome is a genetic disorder that affects connective tissue, which is the material between cells of the body that gives the tissues form and strength. Connective tissue is found all over the body and multiple organ systems may be affected...

The Mucopolysaccharidoses (MPS Disorders) are a group of rare genetic disorders caused by the deficiency of one of the lysosomal enzymes, resulting in an inability to metabolize complex carbohydrates (mucopolysaccharides) into simpler molecules. H...

Multiple epiphyseal dysplasia (MED) is a rare inherited spectrum of disorders characterized by malformation (dysplasia) of the "growing portion" or head of the long bones (epiphyses). Affected individuals may have an abnormally short thighbone (fe...

Hereditary multiple osteochondromas (HMO) is a rare genetic disorder characterized by multiple benign (noncancerous) bone tumors that are covered by cartilage (osteochondromas), often on the growing end (metaphysis) of the long bones of the legs, ...

Polymyalgia rheumatica and giant cell arteritis facts Polymyalgia rheumatica causes pain and stiffness in muscles and joints. Polymyalgia rheumatica is diagnosed by characteristic symptoms associated with abnormal blood te...

Infectious arthritis is an inflammation of one or more joints that occurs as a result of infection by bacteria, viruses or, less frequently, fungi or parasites. The symptoms of Infectious arthritis depend upon which agent has caused the infection ...

Infectious arthritis is an inflammation of one or more joints that occurs as a result of infection by bacteria, viruses or, less frequently, fungi or parasites. The symptoms of Infectious arthritis depend upon which agent has caused the infection ...

Wieacker syndrome is a rare, slowly progressive, genetic disorder characterized by deformities of the joints of the feet (contracture), muscle degeneration (atrophy), mild mental retardation and an impaired ability to move certain muscles of the e...