3D printing has been used for architecture, industrial design, automotive and aerospace engineering. In medicine, 3D printing has had most success with prosthetics, dental work and hearing aids. Nowadays 3D Printing technology has also revolutionized joint replacements.

When Martin Meyers had two meniscus tears four years ago, it got so bad that he couldn't walk a block without stopping. Meyers needed a new knee. In the traditional way, doctors choose a type of knee and cut the bone to make them fit. But Meyers got a new type of knee implant - it was made by a 3-D printer.

Meyers was one of the first patients in the United States to have a 3D printed knee. A company called Conformis printed out the 3D knee which is more precise and more natural compared to the traditional one. Using a patented technology called iFit ConforMIS converts CT data into implants that are precisely sized and shaped to conform to the unique 3D structure of your joint. Its Jig instrumentation uses the same data to create cutting and placement guides that help surgeon determine the exact placement of patient's implant. This reduces surgical time and minimizes the amount of bone cutting required.

"It fits just like an extension of the patient's own anatomy," said Dr. Gregory Martin, an orthopedic surgeon at JFK Medical Center in Palm Beach County. Martin is one of a growing number of doctors in the country who performs knee implants using 3-D printers.

"Just 3 millimeters of an implant being too big can predict pain after the operation, so by sizing it precisely, the hope is the patient will have less pain and a more natural feel," Martin said. "People come in all shapes and sizes and so should their knees."

As for Meyers, he spent six weeks recovering and is now back on the golf course, swinging without pain.

"I don't feel like I have anything in there," he said.