Many funeral homes don't showcase the service. A squeamish public might see this as taking recycling to a bizarre extreme. A British publication headlined a story "The Hip Snatchers."
But other funeral homes and crematoria proudly highlight their efforts.
Recycling is practical, after all. The joints are often made of specialty metals, such as titanium, which is also used in airplanes. It is as strong as steel, but 45 percent lighter.
Although no facility is collecting a lot of material - or, at $12 a pound for titanium, a lot of money - why waste it?
"It doesn't do anybody any good six feet under," said Mark Harris, the Bethlehem author of Grave Matters, about green burials.
"We're all dealing with a shortage of materials," Harris said, "so why source new material when we've got plenty of existing material that can be refashioned and reused?"
Bringhurst Funeral Home at West Laurel Hill Cemetery began to recycle metal joints after it started a green burial program and opened a "natural" burial ground in 2008.
"Everybody's thrilled that we do something for the environment," said Deborah Cassidy, family services director.
People are living longer and medicine is advancing, so it's becoming common for people to die with artificial joints.
In 2009, nearly 400,000 people in the United States received hip replacements, according to the American Academy of Orthopaedic Surgeons. More than 600,000 people got knee replacements.
Plus, more people are being cremated. In 1985, about 15 percent of those who died were cremated, says the Cremation Association of North America. By 2010, that figure had risen to 40 percent.
