The knee disarticulation results in an excellent weight-bearing stump.  It is most often used in children and young adults, but is nearly always avoided in the elderly and patient with ischemic disease.  Several advantages of the knee disarticulation include:  1)  a large end surface covered by skin and soft tissues that is naturally suited for weight bearing;  2)  a long lever arm controlled by strong muscles;  3)  increased stability of the patients prosthesis.  A main disadvantage of the knee disarticulation is cosmetic.  The patient's prosthetic leg will have a knee that extends far beyond his own knee in the sitting position.  This tends to leave the portion of the prosthesis below the knee dangling off the floor when the patient sits.