An 8 year old boy with a history of fall from 10 feet height complains of pain in the right ankle. X-ray taken at that time are normal without any fracture line. But after 2 years, he developed a calcaneovalgus deformity. The diagnosis is –

**Core Concept**
The question is testing the understanding of delayed presentation of a common ankle injury in children, which may not be immediately apparent on X-ray. The underlying concept is that certain types of ankle injuries can lead to long-term deformities if not properly managed.

**Why the Correct Answer is Right**
The boy's initial fall from 10 feet height likely caused a severe ankle sprain, which may have resulted in ligamentous damage or a Salter-Harris type II or III fracture. These injuries can lead to growth disturbances in the tibia and fibula, causing a calcaneovalgus deformity. The normal X-ray at the time of the initial injury does not rule out this diagnosis, as X-rays may not always detect ligamentous injuries or certain types of fractures.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not address the underlying mechanism of the calcaneovalgus deformity.
* **Option B:** This option is incorrect because it implies that the deformity is a result of a direct blow to the ankle, which is not supported by the history.
* **Option C:** This option is incorrect because it suggests that the deformity is a result of a vascular compromise, which is not supported by the history.

**Clinical Pearl / High-Yield Fact**
A calcaneovalgus deformity is a common long-term complication of severe ankle injuries in children, particularly if not properly managed. It is essential to consider this diagnosis in children who present with ankle pain or deformity, even if the initial X-ray was normal.

**Correct Answer:** D.

✓ Correct Answer: C. Tibial epiphyseal injury