Heterotopic ossification is defined as the formation within the soft tissues of abnormal, ectopic lamellar bone containing bone marrow.
|Extensive ossification in the soft tissues around both shoulders in a patient with head injury an year ago|
however the underlying bones are un affected.
It has 3 etiologies:
Trauma (fractures, dislocations, post-surgery, burns)
Genetic (fibrodysplasia ossificans progressiva)
Neurogenic (mainly spinal cord injury and traumatic brain injury)
In a patient with such soft tissue ossification, ask for history of either a direct trauma to that site or trauma/surgery to brain/ spinal cord, one of which is the etiology in most of the cases.