Modular insert exchange in knee arthroplasty for treatment of wear and osteolysis.
Wear and osteolysis have been successfully treated by modular polyethylene exchange in revision hip arthroplasty. However, studies of the same approach in revision knee arthroplasty have not provided similar results. We evaluated the results of isolated polyethylene exchange for wear and/or osteolysis in 68 press-fit condylar TKAs from four centers. At a minimum of 24 months after polyethylene exchange surgery (average, 44 months; range, 24-83 months), there were 11 failures (16.2%). Failures included aseptic loosening in 10 knees and infection in one. With the relatively small cohort size we were unable to identify factors that predicted which knees were more likely to fail: we observed no correlation between failure and patient demographics, component design, or use of cement versus bone graft augmentation. Radiographic review demonstrated no progression of osteolytic lesions in 97% of knees in the study. While the short-term followup limits the conclusions, we believe the 84% success rate with modular polyethylene exchange for wear and osteolysis and the lack of progression of osteolytic lesions in the majority of the knees are encouraging. Full revision of well-fixed total knee components can lead to substantial bone loss, particularly in the face of osteolysis and we therefore consider modular polyethylene exchange in press-fit condylar knees a reasonable option for wear and osteolysis.


METHODS
Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence
Griffin
William L
WL
OrthoCarolina, Charlotte, NC, USA. William.Griffin@orthocarolina.com
Scott
Richard D
RD
Dalury
David F
DF
Mahoney
Ormonde M
OM
Chiavetta
John B
JB
Odum
Susan M
SM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D001863:Bone Screws; D019544:Equipment Failure Analysis; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000000981:diagnostic imaging / Q000601:surgery*; D020959:Polyethylene; D011237:Predictive Value of Tests; D011475:Prosthesis Failure; D011859:Radiography; D012086:Reoperation / Q000379:methods*; D012189:Retrospective Studies; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery
D020959:Polyethylene