When the blood vessels get blocked, they cause damage/death of various tissues. Depending on the kind of tissue damaged the problems present.
The commonest damage is to the Nerves leading to Diabetic Neuropathy. This leads to reduced feeling in the feet. The feet may become numb, you may get a feeling of burning/tingling in the feet. You might get a feeling of something under the feet. Either way, the point to remember is that there is no feeling of pain. So a diabetic may not feel an injury and may keep walking on it, till it worsens and then leads to complications.
Loss of sensation leads to formation of Callus which is brittle and can crack.
SO NEVER WALK BAREFOOT, EVEN IN THE HOUSE.
ALWAYS WEAR SHOES & SOCKS
The other thing that Diabetic Neuropathy does is that it causes deformity in the foot…either hammer toes/trigger toes/bunions and other such toe and foot deformities. These deformities lead to increased pressure on parts which are not designed for pressure. This leads to thickening of the skin and leads to the formation of callosities and corns. These thickened areas are brittle. As patients do not have sensation on their feet, they keep walking on these areas leading to rupture of the skin and the entry of infection.
Another problem which Neuropathy causes is the collapse of the foot leading to something called the CHARCOT FOOT.
REDUCED CIRCULATION/BLOOD SUPPLY/GANGRENE
As the blood vessels get blocked, the supply of blood to the foot reduces. This leads to the inability of the body to fight infection or to repair injury. So the slightest injury to the foot may lead to an ulcer/non healing wound. As and when the blood vessels are unable to deliver the required quantity of blood to the foot it leads to a situation akin to A “HEART ATTACK” OF THE FOOT. The foot tissue dies and leads to GANGRENE.
One of the warning signs of blockage of blood vessels is pain in the calves or midfoot on walking, which is relieved by rest…meaning thereby that you may get pain in the calf or foot on walking or your legs may feel “tired” after walking for a short distance, but when you rest for a few minutes the pain goes away and you are again able to walk. This cycle gets repeated.