Pathophysiology
Clinical meaning
Amputation is the surgical removal of a limb or portion of a limb when tissue viability cannot be maintained or when the limb poses a threat to the patient's life or function. The most common cause of amputation in developed countries is peripheral vascular disease (PVD), typically from atherosclerosis or diabetes mellitus (80% of all amputations). Diabetes is the single largest contributor, with diabetic patients having a 15-40 times higher risk of amputation due to the combined effects of peripheral neuropathy (loss of protective sensation leading to unrecognized injury), peripheral arterial disease (inadequate blood supply for healing), and immunocompromise (increased infection susceptibility). Other causes include trauma (second most common), malignancy (osteosarcoma, soft tissue sarcoma), infection (gas gangrene, necrotizing fasciitis, osteomyelitis refractory to treatment), and congenital limb deficiency. Amputation levels are determined by the most distal level with adequate blood supply for healing: toe, transmetatarsal, below-knee amputation (BKA, most common), above-knee amputation (AKA), and upper extremity amputations. BKA is preferred over AKA when possible because preserving the knee joint significantly improves prosthetic rehabilitation and mobility outcomes. The practical nurse provides comprehensive...