Black patches on male thighs may be caused by trauma, melanoma and ringworm.
1. Trauma: after the patient’s thighs are hit by external force, the venous return of thighs may not be smooth, resulting in venous blood stagnation, so that the blood infiltrates into the subcutaneous tissues from the blood vessels, stimulating the skin and causing changes in the skin, which manifests itself as purplish-black ecchymosis.
2. Melanoma: malignant mutation of melanocytes, manifested as sudden appearance or rapid growth of nevus and other symptoms, if melanoma occurs in thigh area, black plaque can appear.
3. Ringworm: when the fungus infects the skin surface of the patient’s genitals, inner thighs and buttocks, black patches may appear on the skin surface of the thighs.
When the patient has the symptom of black plaques at the thigh, it is recommended to go to the hospital for examination and diagnosis in time and choose the treatment under the guidance of the doctor.