STAGES OF OSTEONECROSIS
|
Clinical Features |
X-Ray Report |
MRI Report |
Stage 1 |
Pain in the groin area |
Normal or minor osteopenia |
Edema |
Stage 2 |
Pain & Stiffness around the joint |
Osteopenia |
Defect + |
Stage 3 |
1.Limping
2.Pain radiating to the knee joint |
Subchondral Collapse
Subchondral Lucency |
Same as X-Ray |
Stage 4 |
1.Unable to move without support
2.Pain on Movement
3.Resting pain can also be experienced |
1.Narrowing of Joint Space
2.Collapsed Surface
3.Sclerosis of Acetabulum |
1.Marginal Osteophytes
2.Collapsed Femoral Head
3.Irregular Joint Space |

CAUSES & RISK FACTORS
Avascular necrosis is caused due to loss/reduction of blood supply to the bone tissue.
Reduced blood supply can be caused by:
Joint or bone trauma
An injury, such as fracture/ dislocation, may damage nearby blood vessels and impairing circulation thus reducing blood flow to bones.
Alcohol abuse
Overconsumption of alcohol over time can cause fatty deposits to form in the blood vessels and can elevate cortisone levels, resulting in a decreased blood supply to the bone.
Medical conditions
Osteonecrosis is associated with other diseases, including
- Caisson disease (diver’s disease or “the bends”)
- Sickle Cell Disease
- Pancreatitis
- Diabetes
- Myeloproliferative Disorders
- Gaucher’s Disease
- Systemic Lupus Erythematosus(SLE)
- Crohn’s disease
- Arterial embolism
- Thrombosis
- Vasculitis
Medications
Use of high-dose corticosteroids, for treating diseases like asthma, rheumatoid arthritis, and systemic lupus erythematosus is a common cause of avascular necrosis.
Although rare but long-term high dose use, to increase bone density for cancers, such as multiple myeloma and metastatic breast cancer, has been linked to osteonecrosis of the jaw.
Idiopathic
- For about 25 percent of people with avascular necrosis, the cause of interrupted blood flow is unknown.