Unfortunately, disease processes and injuries sometimes progress so far as to require a limb to be partially or entirely removed. Of course, an amputation is often a last resort after other attempts at treatment have not successfully resolved the problem.
One of the most common causes is the loss of blood flow. When circulation to the extremities is reduced due to constricted or damaged blood vessels, this is known as peripheral artery disease. If it becomes bad enough, the tissue no longer receiving blood starts to die and become infected. At this point, the best treatment is to remove that dying tissue during an amputation.
Traumatic injury, infection, and an exposure injury like frostbite can also lead to amputations.
In the event of a slow decline in circulation due to diabetes, high blood pressure or cancer, an amputation may be scheduled. Your surgeon will review the need for the surgery and what you should expect both before and after.
If the amputation is the result of a trauma, it will be an emergent situation and taken care of immediately.
Following surgery, physical therapy and possibly a prosthetic device will aid in recovery and adjustment to life without the use of the missing limb or extremity. To be sure, this is a major operation and your surgeon will help coordinate a range of care to help you recover.