3D printing is also being explored as a way to make custom fit prosthetic implants that are surgically implanted directly into the patient's bone, so the prosthetic limb will attach directly to the patient's body. Research into Osseointegration, the surgical integration of prosthetic implants with the amputee's' remaining bone structure, has recently been gaining popularity. The implant will penetrate the skin and connect directly to the bone, so a prosthetic limb can physically be attached to the patient's body. 3D printing can be used to make custom implants made for each patient's specific body, and also to create unique textures that has been shown to speed up the bone/implant integration process. You can read more over on 3DPrint.com: http://3dprint.com/123489/implanting-3dp-prosthetics/