Inexplicable bruising on the thighs indicates a condition of subcutaneous bleeding on the thighs, which is the leakage of blood from inside the blood vessels to outside the vessels. If the patient is a woman of childbearing age, no obvious history of trauma, bruises on the thigh, if the blood test and coagulation routine are not abnormal, the biggest possibility is simple purpura, this disease is common in women of childbearing age, related to the body estrogen concentration changes, often bring more psychological pressure to young women, but no significant impact on the human body The effect is generally better as long as you take vitamin C. If a patient with thrombocytopenia has a reduced number of platelets, the body’s hemostatic function decreases, and bruising can also occur inexplicably, and the most effective method at this time is to replenish platelets or apply platelet-elevating drugs. Of course, patients with coagulation disorders, such as hemophilia A, hemophilia B, and vitamin K deficiency, may also experience inexplicable bruising on the legs, and the most effective method is plasma supplementation and cold precipitation therapy.