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Fibrous Dysplasia | Bone Disease

Posted by: Vicki Joseph | May 21st, 2012

What is Fibrous Dysplasia

Fibrous Dysplasia is a disease in which certain bones – most commonly in the skull, legs and arms – become enlarged and swollen. This can then result in further complications and prolonged medical conditions. Fibrous dysplasia occurs equally amongst men and women and is mostly seen to affect children and teenagers. Although it is not possible to cure a patient of fibrous dysplasia, the symptoms can be ameliorated with certain treatments.

The symptoms of Fibrous Dysplasia

Symptoms commonly include an altered way of walking, in that the patient is usually not able to balance effectively. Some patients also complain of pain in the affected areas, due to the fact that the enlarged bones sometimes squeeze a nearby nerve. In certain cases, fibrous dysplasia can permanently alter the shape of the affected bone and render the patient increasingly susceptible to injury and fracture. Fibrous dysplasia has also been known to result in the onset of other bone-related diseases – such as rickets and arthritis. If fibrous dysplasia is affecting the skull, the change in shape of the bones may result in vision problems, as well as complications with the other senses.

Types of Fibrous Dysplasia

It  can be sub-categorized into three separate diseases: monostotic fibrous dysplasia, polyostotic fibrous dysplasia and McCube-Albright syndrome. The most common of these (affecting about 70% of patients) is monostotic fibrous dysplasia, which affects just one bone in the body, most commonly in the skull. When the disease affects more than one bone it is classed as polyostotic fibrous dysplasia. Approximately 20% of patients are diagnosed with polyostotic fibrous dysplasia. The other 10% of patients are diagnosed with McCune-Albright syndrome – which is most commonly associated with instabilities in hormone levels and alterations in skin pigmentation. The 20% of patients with polyostotic fibrous dysplasia are more likely to develop McCune-Albright syndrome. Symptoms of the latter include overactive glands (in particular the pituitary, parathyroid and thyroid gland), changes in skin pigmentation and early arrival of puberty.

Possible Cause of Fibrous Dysplasia

The cause of fibrous dysplasia is not entirely understood, but its roots seem to lie in a genetic abnormality that changes the rate at which tissue in certain bones grow. Some studies have indicated that fibrous dysplasia is not hereditary, but rather that the gene responsible undergoes a mutation before birth.

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Test Your Knowledge

How Many Bones in the Human Body?

An adult has a total of 206 bones in their skeleton

How many Bones in a Child's Body?

A newborn baby has 270 bones in the skeletal system. Most of their skeleton is made up of cartilage which forms bone as it hardens over time. The bones in a child's skeleton fuse together as they grow, reducing the number, up until about 25 years old.

What is The Strongest Bone in the Human Body?

The femur or thigh bone is the strongest bone in the body. It is situated between the pelvis and the knee. It is also the longest bone in the body and is fully one quarter of your bodies' height.

What is the Weakest Bone in The Body?

The weakest bones in your body are the tiny bones inside your ear that enable you to hear. On the other hand; the most commonly fractured bone is the clavicle.

What is the Hardest Bone in the Body?

The hardest bone in the body is the petrous portion of the temporal bone. The temporal bones are found at the sides and base of the skull and the petrous portion is specifically the part at the base of the skull that contains the organs for hearing.

Where are the Smallest bones in Your Body Located?

The smallest bone in the body is called the stapes. It is a stirrup shaped bone found inside the ear drum that transmits vibrations enabling us to hear.

How many Bones are in the Leg?

A human leg contains 30 bones. There are 26 bones that make up the foot, and the four major bones of the leg, which are the thigh bone (femur), the shin bone (tibia), the calf bone (fibula) and the knee cap (patella)