• Venous insufficiency (70 = 80%)

• Mix disease (Arterio = venous (10 = 14%))

• Arterial disease (2 = 5%)

• Lymphatics (2 = 3%)

• Vasculitis (rheumatoid arthritis, scleroderma, SLE, Wegener’s granulomatosis)

• Neuropathic (diabetes, peripheral neuropathy)

• Traumatic (burns, cold injury, radiation)

• Neoplastic (squamous or basal cell carcinoma, Marjolin’s ulcer, melanoma)

• Sarcoidosis

• Pyoderma gangrenosum

• Others