Patellar component dissociation in total knee arthroplasty. A report of two cases.

Dissociation of the polyethylene from the metal baseplate of the patellar component in total knee arthroplasty (TKA) occurred in two patients. Analysis of intraoperative and postoperative photographs of the specimens indicates that "cold flow" of the polyethylene precedes dissociation from the metal baseplate. The diagnosis can be made on the basis of a pathogonomic metallic crepitus.