The lateral view of ankle demonstrates an avulsion fracture above the posterior calcaneus. There is soft tissue swelling behind the ankle joint with obliteration of the Kager triangle. This patient had ruptured Achilles tendon.

Kager triangle is a clear triangular space in the posterior part of ankle bordered by Achilles tendon, flexor hallucis longus and superior calcaneus. Disruption of this triangle could be due to injury to any of the structures that border the triangle.

Note- Ankle x-ray is not the right imaging modality to diagnose Achilles rupture.