Anyone who must remain immobile in bed or in a chair for more than a few hours at time are susceptible to bed sores. Diabetics are particularly vulnerable to pressure sores on the feet because of lack of blood circulation. When these ulcers become infected, serious trouble results.  While mobility is the best prevention for decubitis ulcers (otherwise known as pressure or bed sores), if a person can't walk around, sheepskin heel protectors can help prevent skin shear and friction wounds.