While artificial hips are typically a successful procedure, total femurs are dicier. One small study from Munich, Germany of 22 cases pegs the failure rate at nearly 60 percent. Failure in that context means that the patient needed another surgery because of serious complications, like a deep infection or the hardware mechanically breaking. (The study’s first author is aware of at least two individuals who ended up having their leg amputated anyway after the study period ended.) Meanwhile, Nicolas Piuzzi, an orthopedic surgeon at the Cleveland Clinic in Ohio, puts the risk of needing a subsequent surgery slightly lower, from 20 to 50 percent at five years following a megaprosthesis’s implantation. In short, it’s risky.