Step 1: Picture the leg being described. The skin just above the ankle becomes hard and tightly bound, while the soft calf above it stays fuller, so the limb looks like a champagne bottle turned upside down.
Step 2: That hardening of skin and fat is the hallmark of lipodermatosclerosis. Long standing venous hypertension drives inflammation and scarring of the subcutaneous tissue, which contracts the ankle region and creates the narrow neck.
Step 3: The condition is part of chronic venous insufficiency and is typically seen in middle-aged women, often with brown pigmentation of the skin.
Step 4: The other options do not match. Dilated surface veins point to varicose veins, sudden painful swelling points to DVT, and a discharging wound points to a venous ulcer. The bottle contour belongs to lipodermatosclerosis.
\[\boxed{\text{Lipodermatosclerosis}}\]