Swelling of the feet, ankles and lower legs is common among aging polio survivors. When indentation marks are left after a finger is pressed hard for several seconds against the skin, it is called “edema.” It results from fluid accumulation due to insufficient pumping action of calf muscles on blood in the leg veins to return it to the heart. Both weakened calf muscles and prolonged sitting positions increase this problem and are common among aging polio survivors as their capacity for frequent walking diminishes or ends.
Additionally, as most people age, the small valves in the leg veins become less effective in preventing blood from dropping backward when standing still and require even more pumping action from calf muscles to prevent dependent edema. Stagnation and engorgement of leg veins increases the risk of blood clots forming in leg veins (known as ‘thrombosis’ or ‘thrombophlebitis’ if warm and painful) and painful enlarged surface veins (known as varicose veins). Edema of both feet and legs can also be a sign of heart, liver or kidney disease and will be worse among people with leg paralysis.
Helpful methods to manage this problem include keeping feet elevated when sitting as much as feasible, elevating legs above heart level when lying down, and wearing tight supportive stockings when out of bed. Careful use of diuretics (water pills) can sometimes be helpful if fluid retention is contributing to the swelling problem. Custom-fitted stockings are commonly necessary and recommended because most pre-sized support hose do now fit evenly and snugly on unusually shaped legs and feet of many polio survivors. It is important to avoid excessive constriction about the abdomen or upper thighs with support stockings or garments because they can prevent the normal return flow of blood from the legs to the heart.
Persistent and severe edema of the feet and legs can lead to skin ulcers and infections. If open infected ulcers persist in chronically swollen paralyzed legs and feet, lymphedema can develop and lead to very severe swelling of the entire leg which improves little with elevation. Aggressive treatment may be needed and may include special compression pumps, compression wraps with medicated wound dressings, and minimal sitting with legs down. Amputation of the limb may become necessary to prevent life-threatening infection.