Rare Bone Diseases

Having a rare disease can be a very frightening and isolating experience. According to the National Organization for Rare Diseases (NORD) of the United States, a "rare disease" is defined as one that affects fewer than 200,000 people.

Unfortunately, there are no cures or treatments for most rare diseases. Since they affect such a relatively small number of people there is not enough funding or scientists interested in researching possible cures.

Rare bone diseases are no different. They are often difficult to diagnose and treat.

Fibrous Dysplasia

• Fibrous dysplasia (FD) can affect any bone in the body and can range in severity from unremarkable to causing severe physical disabilities. For this reason it can go for years without being diagnosed.

  FD results from a poorly understood genetic defect in the cells that form bone. Unlike many genetic defects, it does not seem to be passed down through families but occurs spontaneously in random individuals.

  The first indications that FD might be a problem are bowing of legs and arms, bones that fracture easily and bone pain. Currently, there are no medical treatments for FD, although sometimes surgery is suggested.

Fibrodysplasia Ossificans Progressiva

• Fibrodysplasia Ossificans Progressiva (FOP) is another genetically-based pathology. It causes bone to form in places that it shouldn't, such as tendons, ligaments, muscles and other types of connective tissue. Extra bone can also develop across joints, restricting movement and causing pain.

Gorham's disease

• Gorham's disease occurs when bone resorption occurs. It seems to be a progressive and spontaneous process. The cause is still unknown and there doesn't seem to be any type of pattern or preference as to who is most likely to become victim to it. Most patients will not know they have it until they fracture a bone and it fails to heal correctly.

  No preventative or treatment measures currently exist.

Melorheostosis

• The main symptom of melorheostosis is progressive thickening of the bones, joints and the soft tissue and skin that is on top of them. People with melorheotosis experience severe pain, progressively limited motion and malformed or immobilized joints, tendons and ligaments.

Osteogenesis Imperfecta

• Osteogenesis Imperfecta (OI) or "brittle bone" disease is a genetic disorder that causes the bones to break extremely easily. A person who is affected by OI could break an arm by bumping against a countertop, or break a rib by rolling over while sleeping.