Can you explain the difference between leg amputation at or above the knee?

Yes: It is preferable if possible to save the knee as there is then less work in walking and thus less demand on the heart. Walking is also more natural. Every surgeon tries to therefore save the knee, but if the blood suply is poor at the knee, there is infection close to the knee, the patient does not walk or has a contracture (chronically bent knee), etc; an above knee ampution may be the only option.

Mobility: Through knee amputations are unusual. The level at which an amputation is performed is based on the viability of the remaining tissue, the blood flow, and/or level of infection. That being said, above knee amputations typically heal easier, while below knee amputations afford greater mobility or walking.

Similar: Amputations at the level of the knee (thru the knee joint) are uncommon in adults as the function of the knee is lost and it is difficult to fit with a prosthetic knee. Must commonly amputations are done above the knee (transfemoral). If possible it is good to try to save the knee with a below the knee amputation as it is easier to walk and it takes much less energy that above the knee.