Heterotopic Ossification

(HO)

Pronounced: Het-toro-toe-pik Oss-if-a-kay-shun

by Patricia Griffin Kellicker, BSN

Definition

Heterotopic ossification (HO) is the growth of bone in places where it’s 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 of HO is unknown. There may be a genetic link. HO can also happen because of trauma.

Risk Factors

Your chances of HO are higher if you have:

Traumatic brain injury or stroke
Recent spinal cord injury—mainly within the past 1-4 months
Hip surgery or other joint surgery
Burns
Long period of immobility
Joint infection
Fractures
Some tendon injuries

Symptoms

Symptoms depend on how serious HO is. It also depends on where there is bone growth. HO may cause:

Decreased range of motion
Swelling or redness to joint(s)
Pain
Fever

Diagnosis

The doctor will ask about your symptoms and health history. You may also have:

A physical exam
Blood and urine tests
Tests on fluids from your skin or cysts
Imaging tests:
- CT scan
- Ultrasound
- Bone scan
- X-ray

You may be referred to a specialist.

X-ray of Pelvic Repair

HO may not show up on x-ray until later stages.

Treatment

The level of care needed depends on how serious HO is. Care may involve:

Physical Therapy

Therapy is an important part of your care plan. Range of motion exercises will help to move around better. It can also keep the HO from getting worse. This may include stretching and strength training.

Medications

Your doctor may advise:

Non-steroidal antiinflammatory drugs (NSAIDs) to reduce swelling and pain
Bisphosphonates to prevent the bone loss

Radiation Therapy

Radiation therapy may help prevent abnormal bone growth, mainly after hip surgery.

Surgery

Surgery may be used to remove the abnormal bone. This will help improve range of motion. Radiation therapy and medicines are mainly used after surgery to prevent recurrence.

Prevention

There’s no way to prevent HO because the cause isn’t known. If you’re at high risk for HO, talk to your doctor.

RESOURCES:

Ortho Info—American Academy of Orthopaedic Surgeons
https://www.orthoinfo.org

United Spinal Association
https://www.unitedspinal.org

CANADIAN RESOURCES:

Canadian Orthopaedic Association
http://coa-aco.orgaco.org

When it Hurts to Move—Canadian Orthopaedic Foundation
https://whenithurtstomove.org

References:

Back DL, Smith JD, Dalziel RE, Young DA, Shimmin A. Incidence of heterotopic ossification after hip resurfacing. ANZ J Surg. 2007;77(8):642-647.

Heterotopic ossification. Craig Hospital website. Available at: https://craighospital.org/resources/heterotopic-ossification. Updated January 2015. Accessed June 21, 2018.

Pape HC, Marsh S, Morley JR, Krettek C, Giannoudis PV. Current concepts in the development of heterotopic ossification. J Bone Joint Surg Br. 2004;86(6):783-787.

Spinal cord injury—InfoSheet #12. Spinal Cord Injury Information Network website. Available at:
...(Click grey area to select URL)
Accessed June 21, 2018.

Zychowicz ME. Pathophysiology of heterotopic ossification. Orthop Nurs. 2013;32(3):173-177.

Last reviewed May 2018 by EBSCO Medical Review Board Marcie L. Sidman, MD
Last Updated: 6/21/2018

EBSCO Information Services is fully accredited by URAC. URAC is an independent, nonprofit health care accrediting organization dedicated to promoting health care quality through accreditation, certification and commendation.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

To send comments or feedback to our Editorial Team regarding the content please email us at healthlibrarysupport@ebsco.com. Our Health Library Support team will respond to your email request within 2 business days.