16 year old male presents with extensive heterotropic ossification over the neck, back & shoulders and decreased chest movements. He gives history of progressive immobility since the age of 3 years. Which of the following statement about his affecting condition is not true ?

**Core Concept**
The patient's condition is characterized by the abnormal formation of bone tissue outside of the skeleton, leading to progressive immobility. Heterotopic ossification (HO) is a process where mesenchymal cells differentiate into osteoblasts, resulting in the formation of bone within soft tissues.

**Why the Correct Answer is Right**
The patient's condition, likely fibrodysplasia ossificans progressiva (FOP), is a rare genetic disorder caused by mutations in the ACVR1 gene. This leads to the activation of the BMP signaling pathway, promoting the differentiation of mesenchymal cells into osteoblasts. The formation of heterotopic bone in soft tissues, such as muscles and tendons, results in progressive immobility and restricted movement. The patient's history of progressive immobility since the age of 3 years is consistent with FOP.

**Why Each Wrong Option is Incorrect**
**Option A:** FOP is characterized by the formation of heterotopic bone in response to injury or inflammation, which is not true. FOP is a genetic disorder that leads to spontaneous formation of heterotopic bone.
**Option B:** FOP is not associated with mutations in the COL2A1 gene, which is related to osteogenesis imperfecta. FOP is caused by mutations in the ACVR1 gene.
**Option C:** FOP is not typically associated with a history of trauma or injury. However, it is worth noting that minor traumas can trigger the formation of heterotopic bone in some patients with FOP.

**Clinical Pearl / High-Yield Fact**
Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder with a prevalence of approximately 1 in 2 million. It is characterized by the formation of heterotopic bone in soft tissues, leading to progressive immobility and restricted movement.

**Correct Answer:** A.

✓ Correct Answer: A. They have a near normal life expectancy