The partial knee replacement that former President George W. Bush underwent earlier this week has focused attention on what is one of the most rapidly expanding medical procedures being performed today.

  Dr. Sergio Viroslav, a knee specialist at the San Antonio Orthopaedic Group, says it is an example of 'the right procedure for the right time.'  He says knee replacement technology has matured at exactly the same time as the Baby Boomer generation is refusing to slow down, just because they're reaching their fifties and sixties.

  "The American public is not interested in sitting around waiting to get old," Dr. Viroslav said.

  He says the procedure is simple and no longer considered 'experimental,' which means partial and total knee replacements are covered by insurance and Medicare.  He says for many patients, like Mr. Bush, a partial knee replacement is the better option.

  "The advantage of the partial joint replacement is the knee has a tendency to feel more like their original knee."

  He says a 'partial' replacement is a 'temporary fix,' which generally lasts between five and ten years, and then the patient will have to decide whether to take additional steps.  But Dr. Viroslav says for increasingly active Baby Boomers, it is the difference between the cane and the rocking chair, which has been the image of older people for generations, and the active lifestyle that people want to have today.

  "Nowadays these can be done as outpatient operations with less of a chance of complications, people really are flocking and deciding 'this is for me'," he said.  "People are looking for things that keep them active and involved with golf, tennis, hiking.  Because patients today are demanding this, saying 'hey doc, I want to be better, I want to resume what I was doing, I don't want to sit around on the couch."

  He says remaining active is the best way to stave off other conditions like weight gain and diabetes.

  Dr. Viroslav says many patients who come to him have been athletic, like the former President, and are suffering from knee problems specifically because of that.

  "We don't want to wait around getting older," he said.  "People are really looking around for things that keep them active."