The more you scratch the outside of your ankles, the more itchy they get. It may be caused by neurodermatitis, atopic dermatitis, hypertrophic lichen planus and other diseases. 1. Neurodermatitis: the cause is not clear, may be related to mental factors, local friction stimulation and other factors. Patients will appear localized tinea-like changes, accompanied by intense itching, can be seen on the back, limbs, trunk and ankles and other parts. 2. Atopic dermatitis: the cause may be related to genetic factors, environmental factors, immune abnormalities and other reasons. The main manifestations are dry skin, intense itching, usually aggravated by scratching and excessive washing, and can occur in the ankles, popliteal fossa, elbow nodes and other places. 3. Hypertrophic lichen planus: the cause of the disease may be related to heredity, infection, mental and other factors. Patients will appear local purple-red flat papules, often accompanied by itching, preferably around the ankles, calves and other parts of the anterior. If the outside of the ankle is itchy, it is recommended to go to a regular hospital for examination to clarify the cause of the disease.