Abstract
The introduction of microporous metallic implants into which bone can grow to stabilize the implant has necessitated considerable work prior to clinical studies. Ten years of bench and animal testing have resulted in a clinically available prosthesis with a multilayer porous coating with a pore size of 50-300 mu. Initial clinical trials with a 50-100 mu hip prosthesis indicated the necessity to increase the pore size to 300 mu and clinical studies of such prostheses are at present underway.