Heterotopic Ossification
Condition
(HO)
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.
HO can lead to pain and movement problems. Treatment can improve outcomes.
Causes
The cause of HO is not known. It may be due to genes or trauma.
Risk Factors
Things that may raise the risk of HO are:
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
The doctor will ask about symptoms and past health. A physical exam will be done. The person may be sent to a specialist.
Tests may include:
- Blood and urine tests
- Tests on fluids from the skin or cysts
- Imaging tests, such as:
HO is diagnosed based on test results.
HO may happen after joint surgery.
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Treatment
The level of care needed depends on how serious HO is. Options are:
- Physical therapy to increase strength, flexibility, and range of motion—depending on the location of the problem
- Medicines to:
- Ease swelling and pain
- Prevent the bone loss
- Treat flare-ups of HO
- Radiation therapy to prevent abnormal bone growth
- Surgery to remove abnormal bone
Prevention
There are no known guidelines to prevent HO.
Ortho Info—American Academy of Orthopaedic Surgeons
United Spinal Association
CANADIAN RESOURCES:
Canadian Orthopaedic Association
When it Hurts to Move—Canadian Orthopaedic Foundation
Ortho Info—American Academy of Orthopaedic Surgeons
United Spinal Association
CANADIAN RESOURCES:
Canadian Orthopaedic Association
When it Hurts to Move—Canadian Orthopaedic Foundation
References
- Fibrodysplasia ossificans progressiva. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/fibrodysplasia-ossificans-progressiva.
- Heterotrophic ossification. Cleveland Clinic website. Available at: https://my.clevelandclinic.org/health/diseases/22596-heterotopic-ossification.
- Heterotopic ossification. Craig Hospital website. Available at: https://craighospital.org/resources/heterotopic-ossification.
- Spinal cord injury. National Institute of Neurological Disorders and Stroke website. Available at: https://www.ninds.nih.gov/health-information/disorders/spinal-cord-injury.
Contributors
- Daniel A. Ostrovsky, MD
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