Heterotopic Ossification

Why do Bones Grow in Soft Tissue after Head Trauma?

Head trauma and traumatic brain injury affect many systems of the body. Long recovery times, decreased physical activity and changes in the body’s metabolism can cause a host of unusual effects. One complication that occurs in some individuals who have suffered severe head trauma is a condition called Heterotopic Ossification (HO). 

Heterotopic ossification is the development of bone in places where bone does not belong.

It is correlated with neurological injury. Heterotopic ossification occurs in the body’s soft tissues, not the brain or skull where the original injury occurred. The more severe the brain injury, the more likely that the person will develop HO.

The exact physiologic cause of HO is still being explored by scientists; however, there is evidence of a relationship between nervous system injury and abnormal soft tissue bone growth. Specifically, neuropeptides and neurotransmitters have been found in areas where there is abnormal bone growth.

Most of the time, HO occurs around major joints that are filled with synovial fluid and are surrounded by muscles which have a risk of going into spasm. HO is often seen in the hip area but can also be found on the elbows, knees, in the ankles and shoulders.


Patients who have neurological associated heterotopic ossification, usually feel there is reduced range of motion throughout the affected area and the joint.

Although pain is possible, this isn’t the most common presenting complaint when the ossification develops after head trauma.

The symptom of reduced range of motion may begin before there is actual observable bone development via an x-ray. It usually takes about 3-4 weeks for enough calcium and bone cells to build up, for the ossification to be observable on the x-ray.

If the ossification progresses, it can lead to a “frozen” joint that no longer works the way it should.

HO affects the quality of life in the post head trauma patient because it adds to any existing mobility challenges that occurred due to the head trauma. If new disabilities develop secondary to frozen joints there is a higher risk of associated complications.

HO can interfere with walking, transferring from lying down to sitting and standing. This can slow the overall head trauma recovery progress. HO interferes with an individual’s ability to perform daily tasks such as cooking or bathing.

According to the research, neurological heterotopic ossification makes it more likely to develop a host of serious complications such as bladder infection, pressure ulcers, and pneumonia. These can all contribute to decreased quality of life, and increased risk of dying.


Anti-inflammatories are sometimes used to slow or stop the development of the bone. Simple over the counter medications such as ibuprofen can be helpful if approved for use by your physician.

Physical therapy is an essential element of recovery and keeps the body’s joints moving. Physical therapy prevents muscle contractures and joint stiffness in areas that are particularly at risk of freezing up if heterotopic ossification develops.

Surgery may be necessary to remove the unwanted bone cells, and free the joint. However, sometimes surgery can also stimulate the development of HO, so careful planning and management is necessary.

There is some controversy about when it’s best to perform surgery, with a number of surgeons feeling it is best to get it done early, rather than wait until there is a larger bone mass to remove, which could be more difficult and restrictive. A single dose of radiation may also be tried to prevent abnormal bone cell formation.

It’s important to remember that head trauma affects the body as a whole, and recovery from brain injury involves all body systems.


Gil, j. A., Waryasz, g. R., Klyce, w., & Daniels, a. H. (2015). Heterotopic Ossification in Neurorehabilitation. Rhode Island Medical Journal, 98(12), 32-34.

Hong-wei, M., Ke-min, L., Xin-zuo, H., & Rui, G. (2014). Management of multijoint stiffness of bilateral upper limbs secondary to heterotopic ossification: Case report and literature review. Journal Of Rehabilitation Research & Development, 51(3), 497-502 6p. doi:10.1682/JRRD.2013.03.0073

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