Last year, after many years of physical therapy, cortisone shots, and experimental treatments to prop up my failing knees, I decided to go bionic and get full knee replacements. Holding out hope for more than a decade that emerging cell-therapy technology would offer breakthrough cartilage regeneration, I waited until I had no cartilage left to regenerate. My gait was increasingly resembling the scarecrow from The Wizard of Oz.

Now, I already had some vicarious experience with knee replacements, because my wife, Maureen, had the surgery 10 years earlier. I was inclined to use the same doc, as Maureen’s experience had been great. But then a few of my lean friends offered alternative solutions involving new methods and materials; cutting-edge, custom-formed prostheses; even robotic surgery, which I’m told is becoming commonplace. “Less chance for error,” they told me, “lower cost,” and “faster recovery.”

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