This leaflet provides clear, practical information about Heterotopic Ossification (HO) that may develop after an injury or surgery to the elbow. It is designed to support patients, their families, and caregivers throughout diagnosis, treatment, and recovery.
WHAT IS HETEROTOPIC OSSIFICATION (HO)?
HO is the abnormal formation of mature bone in soft tissues where bone does not normally grow. After elbow trauma, this bone can form around muscles, ligaments or the joint capsule, leading to stiffness or even fusion of the elbow.
WHY DOES HO HAPPEN AFTER ELBOW INJURY?
HO can develop after:
- Elbow fractures or dislocations
- Surgical fixation or reconstruction of the elbow
- Burns, head injury, or prolonged immobilisation
The exact cause is not fully understood. However, it involves a chain reaction triggered by trauma, where healing signals encourage immature cells to turn into bone-forming cells in the wrong place.
WHO IS MOST AT RISK?
HO is more likely after elbow injury or surgery if:
- The injury is severe or involves multiple structures
- There is a delay in starting movement exercises
- The joint was immobilised for a long time
- The patient has other neurological injuries, such as brain or spinal cord trauma
- There is ongoing inflammation, infection, or bleeding into the joint
WHAT ARE THE SIGNS AND SYMPTOMS?
HO usually develops within 3 to 12 weeks after injury or surgery.
Early signs include:
- Pain or discomfort around the elbow
- Swelling or warmth over the joint
- Reduced range of motion (difficulty bending or straightening the arm)
Later signs may include:
- A firm lump or thickening around the elbow
- Stiffness that gradually worsens
- Loss of functional movement
- In severe cases, complete joint fusion (ankylosis)
These symptoms may resemble infection or deep vein thrombosis, and need assessment.
HOW IS HO DIAGNOSED?
Diagnosis is based on symptoms, physical examination, and imaging:
- Ultrasound can detect early soft tissue changes
- X-rays become helpful after 4–6 weeks, once calcium is visible
- CT scans show the precise size, location and extent of bone formation
- MRI may be used to evaluate nearby soft tissues
- Bone scans detect early changes and may guide treatment planning
- Blood tests sometimes show raised alkaline phosphatase when bone is forming, but this is not specific
HOW IS HO TREATED OR PREVENTED?
Prevention strategies (especially after elbow surgery):
- Early, gentle movement exercises (within comfort limits)
- Short-term anti-inflammatory medicines (NSAIDs) such as indomethacin, which reduce new bone formation
- Low-dose radiotherapy, occasionally used around the time of surgery to reduce risk in high-risk patients
Treatment options (for established HO):
- Physiotherapy to maintain movement and reduce stiffness
- Pain management with medication or local treatments
- Surgical removal of heterotopic bone if it severely limits movement or causes pressure symptoms
- This is usually done after the bone has matured (6–18 months after onset)
- Follow-up treatment may include NSAIDs or radiotherapy to reduce recurrence
WILL I GET FULL MOVEMENT BACK?
This depends on the severity of HO, the timing of treatment, and your rehabilitation. Many patients regain good function with a combination of physiotherapy and, if needed, surgery. Early detection and regular movement can improve outcomes.
PATIENT FAQs
Is HO the same as a bone spur?
Not exactly. HO is abnormal bone in soft tissues, whereas bone spurs form on bone surfaces.
Can I prevent HO by staying still?
No. In fact, early movement (within a safe range) is key to prevention. Prolonged immobilisation increases the risk.
Does HO always need surgery?
No. Mild cases may improve with physiotherapy alone. Surgery is reserved for cases where movement is severely restricted or painful.
KEY POINTS TO REMEMBER
- HO is a known complication after elbow trauma or surgery
- Look out for swelling, pain, and stiffening of the joint
- Early, gentle physiotherapy reduces risk
- Medication and radiotherapy may help prevent HO
- Surgery may be required if function is significantly affected
WHAT TO DO NEXT
If you’ve recently had an elbow injury or surgery, speak to your doctor or therapist about your risk of HO. Ask if you need a physiotherapy plan or preventive medication.
For elbow rehabilitation videos, HO factsheets, or clinic appointments, visit www.TheArmDoc.co.uk
To contact us, phone 020 3384 5588 or email Info@TheArmDoc.co.uk
DISCLAIMER
This leaflet is for educational purposes and does not replace advice from your medical team. All decisions should be made in consultation with your healthcare provider.