Long-Term Survivorship and Failure Modes of 1000 Cemented Condylar Total Knee Arthroplasties

The purpose of this study was to examine the factors affecting survivorship and to analyze the reasons for reoperation and revision of a cemented modular condylar total knee arthroplasty (TKA). One thousand eight consecutive primary cemented cruciate retaining TKAs performed at one institution from 1987 to 1989 were studied. At the time of this study, 411 patients (562 knees) had died, 43 patients (45 knees) had their knee components revised or removed, and 47 patients (62 knees) were lost to follow-up. Two hundred forty-four patients (331 knees) were alive and had not had their TKA components removed or revised at the time of latest follow-up. Mean follow-up of living patients with components in situ was 15.7 years (range, 14.5-17.9 years). Survivorship at 15 years for component removal for any reason, revision for any reason, revision for mechanical failure, and revision for aseptic loosening were 93.7%, 95.9%, 97.0%, 98.8%, respectively. Survivorship for the first three end points was significantly poorer among patients younger than 60. Forty-five knees had components removed or revised: approximately one third were removed for infection (16/45), one third for aseptic loosening or tibial polyethylene wear (16/45), and one third for other causes. Twenty knees had reoperations that did not involve component removal or revision (mostly periprosthetic fracture or infection). Mechanical implant failures accounted for less than half of the reoperations and revisions in the first 15 years after arthroplasty, whereas infection and periprosthetic fractures accounted for a substantial portion of revisions and reoperations. As mechanical arthroplasty failures have become less common, other modes of complications related to the arthroplasty have become proportionately more frequent.