Patchy shadowing of the talus is, in general, not osteonecrosis of the talus. Patchy shadow of the talus may be a sign of severe localized infection, edema and damage to the bone. However, the condition cannot be fully determined by X-ray examination, but needs to be combined with the patient’s medical history and other examinations, and then through the doctor’s experience to make a clear diagnosis. Osteonecrosis of the talus may be related to trauma and is mainly caused by trauma. Its main symptom is pain, which in severe cases can cause impaired movement of the joints around the bone. The presence of talus necrosis can be checked by X-rays, CT, or even MRI. If a patient has abnormal test results such as talus patch shadow, it is recommended that he or she seek prompt medical attention to identify the cause of the condition with the help of a doctor and get targeted treatment or therapy.