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Osteonecrosis | What is Osteonecrosis?

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)