The various causes of leg
pain are atherosclerosis, deep vein thrombosis - leg
pain on walking (A blood clot
in a deep vein), Leriche syndrome (block in abdominal aorta and/or main leg artery), limb ischaemia (low oxygen to limbs), sciatica, spondylitis of lower vertebrae and peripheral vascular disease (arteries of limbs are involved). A color Doppler test will rule out the possibility of involvement of an artery or vein and its blockage by a clot.