Retrieval analysis of porous-coated components for total knee arthroplasty. A report of two cases.

Retrieval analysis of two total knee replacements incorporating porous-coated components for biologic fixation was performed. The significant finding in a 63-year-old woman was fracture of the porous-coated metal backing of the tibial component, secondary to aseptic loosening. The significant findings at the time of revision surgery in an 82-year-old woman were nonuniform bone ingrowth (primarily around fixation pegs) and fracture of metal beads from the metal backing of the patellar component.