Unilateral lower leg swelling. Wear compression socks and elevate feet for saphenous reflux, leg remains same size. Might swelling not be vascular?

No. you have venous stasis. Any other swelling can be like abscess formation, muscle herniation. Fracture, and if you have the above trust me you will know it right away. My advice if you have good arterial flow get 30-40mmHg compression sock and use them. Cut salt from diet and elevate feet when at rest .