Definition

Heterotopic ossification (HO) is the growth of bone in places where it is not supposed to be. It can happen anywhere in the body. The hip, knees, shoulders, and elbows are the most common places. Growths can be small or large.

Causes

The cause is not known. It may be due to genes or trauma.

Risk Factors

Things that may raise the risk of this problem are:

• Traumatic brain injury or stroke
• Recent spinal cord injury
• Hip surgery or other joint surgery
• Burns
• Long period of inactivity
• Joint infection
• Fractures
• Some tendon injuries

Symptoms

The problems a person has depends on how serious HO is. It also depends on where there is bone growth. Problems may be:

• Poor range of motion
• Joint swelling or redness
• Pain
• Fever

Diagnosis

You will be asked about your symptoms and health history. A physical exam will be done. You may be sent to a specialist.

These tests may also be done:

• Blood and urine tests
• Tests on fluids from the skin or cysts
• Imaging tests:
  • CT scan
  • Ultrasound
  • Bone scan
  • X-ray

X-ray of Pelvic Repair HO may happen after joint surgery. Copyright © Nucleus Medical Media, Inc.

Treatment

The level of care needed depends on how serious HO is. Choices are:

• Physical therapy to increase strength, flexibility, and range of motion, depending on the location of the problem
• Medicines, such as:
  • Nonsteroidal anti-inflammatory drugs (NSAIDs) to ease swelling and pain
  • Bisphosphonates to prevent the bone loss
• Radiation therapy to prevent abnormal bone growth
• Surgery to remove abnormal bone

Prevention

There are no known guidelines to prevent this health problem.