Patients with hard lumps on their thighs need to consult different departments depending on the nature of the lumps. A. If a patient has a large hemangioma in the thigh due to the abnormal proliferation of local blood vessels, it may appear as a hard mass. At this time, the patient needs to consult the vascular surgery department, and the specific situation of the hemangioma can be clarified through angiography or ultrasound examination, and if necessary, surgery can be performed to remove the hemangioma to avoid serious bleeding caused by rupture of the hemangioma. If the patient has melanoma on the thigh, it can form a hard local mass. As melanoma is a tumor of high malignancy, it is necessary to remove the tumor and the surrounding tissues as soon as possible to avoid widespread metastasis of malignant tumor, which may cause serious complications. If trauma to the thigh causes a local tendon hematoma, the patient needs to consult an orthopedic surgeon for hematoma debridement to reduce the local pain.