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 is normal without any fracture line. But after 2 years, he developed a calcaneovalgus deformity. The diagnosis is :
Undiagnosed malunited fracture Avascular nercrosis talus Tibial epiphyseal injury Ligamentous inj ury of ankle joint