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Fibrodysplasia Ossificans Progressiva

Posted by: Vicki Joseph | May 30th, 2012

What is Fibrodysplasia Ossificans Progressiva ?

FOP Disease is a highly uncommon disorder that causes fibrous tissue at the connecting point between bones in the body to become rigid. This results in common fractures sometimes resulting in permanent disfigurement, as the body is unable to repair the ligament and tendons between the broken bones, as these have become inelastic and bone-like in their structure.

Fibrodysplasia ossificans progressiva is a genetic disorder and the symptoms often present themselves in early childhood. Normal bone growth occurs first in the cranium, then down toward the torso and finally in the legs and feet. As such, the symptoms of fibrodysplasia ossificans progressiva are often seen to occur in the same order, first in the top of the body and progressively further down as time passes.

The serious problems associated with fibrodysplasia ossificans progressiva begin when the patient becomes injured, as the connecting muscle tissues in joints are unable to repair themselves efficiently, and become fixed in place. Whereas a person unaffected by the disease is able to recover after fracture, the bone of a person with fibrodysplasia ossificans progressiva can be permanently locked into its new position. The reason for this is that the new bone formed at the site of the injury can fuse with the existing bones, rendering recovery virtually impossible.

The process that hardens muscle tissue into bone is one that begins in the womb and allows the foetus to develop a normal skeletal structure. Usually this process is deactivated by a gene shortly after all the bones in the body have formed. However, in patients with fibrodysplasia ossificans progressiva, the gene is never deactivated and continues to transform muscle into bone throughout the life of the patient.

As the disease is so rare, doctors often fail to correctly diagnose fibrodysplasia ossificans progressive, and incorrectly assume it to be various forms of cancer. This means that biopsies are often ordered in vain, which can actually render the condition more aggressive.

There is no cure or indeed effective treatment for fibrodysplasia ossificans progressiva. Surgery is not effective for skeletal disease, as removal of the newly formed bone merely accelerates the bone-forming gene into ossifying more soft tissue.

Primary Hyperparathyroidism

Posted by: Vicki Joseph | May 27th, 2012

What is Primary Hyperparathyroidism?

Hyperparathyroidism is a condition that raises calcium levels in the blood. Once the calcium levels are above a certain threshold (usually about 2.7 mmol/L) the condition is known as hypercalcemia. The abnormally high calcium levels are caused by the overactive secretion of parathyroid hormone (PTH), which in turn is usually caused by a non-cancerous tumor (adenoma) in one or more of the small endocrine glands (parathyroid glands) of the neck.

Primary hyperparathyroidism is genetic, but not hereditary, in the sense that it is caused by the mutation in the parathyroid glands after birth. The condition has been found to be more prevalent in areas with high radioactivity, such as in the contamination zone around the Chernobyl nuclear power plant. This is thought to be caused by dangerously high strontium levels in the atmosphere.

Symptoms of Primary Hyperparathyroidism

It is more likely to affect women than men and the symptoms vary considerably and include:

Primary hyperparathyroidism is detected via blood tests or calcium infusions for more accurate results.


The most common treatment is to remove the affected gland entirely via surgery. Patients with mild forms of the disease sometimes respond to hormone therapy, and there are some newly released medications that are able to limit the secretion rate of the parathyroid glands.

The main bone-related conditions associated with primary hyperparathyroidism are osteomalacia and osteitis fibrosa cystica. Osteomalacia is the term generally applied to rickets when affecting adults and has the same pathology (http://www.learnbones.com/rickets-disease-in-children).

Osteitis fibrosa cystica affects the skeletal structure by increasing the rate at which bone cells are broken down, causing reduced bone density and increased likelihood of fracture. The breakdown of bone is caused by cells known as osteoclasts, which are programmed to remove living bone cells. Once Bone Disease exceeds the rate at which new bone cells are created the bone begins to degenerate.

Osteonecrosis | What is Osteonecrosis?

Posted by: Vicki Joseph | May 15th, 2012

What is Osteonecrosis?

Osteonecrosis also known as avascular necrosis, is a condition that causes restricted blood supply to bones, resulting in premature death of cells. The ailment most commonly affects the coxa (hip) and scapula (shoulder), but is also seen in the patella (knee joint), ginglymus (elbow), carpus (wrist) and talocrural joint (ankle).

If osteonecrosis is not treated, the lack of blood flow to the bone will result in deterioration of bone matter, leading to arthritis and possible collapse. Osteonecrosis can have several causes, such as various bone diseases, overuse of anabolic steroids, alcohol abuse, ineffective pressure recovery from deep-sea diving, dislocation and fracture. Some other non bone-related diseases have also been known to cause or exacerbate osteonecrosis, such as diabetes and gout. In rare cases osteonecrosis can occur without any traceable cause – in which case it is labeled “idiopathic osteonecrosis”.


Osteonecrosis is notoriously difficult to detect in its early stages, as the condition is not associated with any pain or external symptoms until the damage has worsened to a significant degree. At later stages, osteonecrosis will result in ever-increasing pain, which may become extremely difficult to manage in case of collapse. The disease can also result in limited maneuverability in the affected joints, and it can permanently affect the gait of a patient if the damage to the hip or knee is sufficient.

Osteonecrosis is effectively impossible to prevent, as its causes are so varied and the progression of the disease is so poorly understood. Patients who wish to minimize the risk of osteonecrosis developing later in life can do so by avoiding over-use of steroids and alcohol, and taking care to follow correct decompression techniques after deep-sea diving.Your physician may suggest one or more scans to determine the extent of the disease, such as CT, MR, bone scans and x-days.


The treatment for osteonecrosis varies depending on the condition that caused the disease to begin with. In the majority of cases, patients with osteonecrosis will need to undergo surgery in order to excise the dead bone tissue and prevent further damage. The effectiveness of surgery varies greatly depending on the age, gender, weight and overall lifestyle and medical history of the patient in question. The bone disease can be eradicated entirely or it can result in permanent damage.

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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)