Relationship between wear debris particles and polyethylene surface damage in primary total knee arthroplasty.

To study relationships between design and wear, particles were isolated from tissues around 75 failed primary total knee prostheses, and particle size and concentration were compared with the extent and distribution of wear on superior and inferior polyethylene surfaces of the corresponding implants. Twenty-four heat-pressed, posterior cruciate ligament (PCL)-retaining (group I: PCA knee), 19 non-heat-pressed, PCL-retaining with relatively flat surfaces (group II: AMK, Kinematic, Microloc, Ortholoc), 14 non-heat-pressed, PCL-retaining with relatively congruent surfaces (group III: Townley Arizona), and 18 PCL-resected implants (group IV: Insall-Burstein, Total Condylar) were evaluated. Groups III and IV had fewer particles, smaller particles, and less surface damage than groups I and II. Implants with third-body wear had relatively small debris particles; those with thinner polyethylene had more severe surface delamination and more wear between liner and metal base. Groups I and II had more rotationally asymmetric wear patterns than groups III and IV. The size and concentration of debris particles might reflect, in part, different dominant wear mechanisms among implants of different designs.