There is a bulge on the medial side of the welcoming bone of the calf, which is painless and itchy, and it may be caused by lipoma, sebaceous cyst, old damage mechanization, and periosteal hyperplasia. 1. Lipoma: Lipoma may be caused by genetic factors, chronic inflammation, and may appear in various parts of the limbs, trunk, back, shoulders, etc. It is characterized by painless and itchy, but there will be skin bulging. 2. Sebaceous cysts: small bumps on the legs due to blocked follicular sebaceous gland orifices, which are also painless and itchy, but if secondary bacterial infections occur, there may be redness, swelling, fluctuating sensation and other symptoms. 3. Stale injury mechanization: If the inner calf was once injured, soft tissue damage, subcutaneous hemorrhage, etc., the formation of tissue mechanization during the recovery process, you can form a hard small bulge, and there is no pain or itching symptoms. 4. periosteal hyperplasia: the front inside of the tibia may be due to trauma impact and other factors lead to local periosteal hyperplasia, thickening, forming a bulge under the skin, generally no pain and itching symptoms. Inner calf bulge may also be caused by other reasons, it is recommended to observe, once the change, timely medical care.