Abstract
Liner exchange and bone grafting are commonly used in cases of wear and osteolysis around well fixed acetabular components in revision total hip arthroplasty. However, in total knee revision, liner exchange is a more rare option.
In a multicenter study, we evaluated 22 TKAs that were revised with liner exchange and bone grafting for wear and osteolysis. All knees were well fixed and well aligned, and all components were modular tibial components. Osteolytic areas averaged 21.1 cm2 and 7.6 cm2 on AP projections of the femur and tibia, respectively, and averaged 21.6 cm2 and 5.7 cm2 on lateral projections of the femur and tibia, respectively, with the largest area being 54 cm2 on a single projection. Follow up was minimum 2 years and average 40 months. No knees were revised and radiographically, all osteolytic lesions showed evidence of complete or partial graft incorporation. In addition, there was no radiographic evidence of loosening at final follow up.
The Mayo Clinic evaluated 56 isolated tibial insert exchange revisions at their institution. Cases of loosening, infection, knee stiffness, or extensor mechanism problems were excluded. At minimum 2 year follow up (average 4.6 years), 14 knees (25%) required re-revision.
Baker et al evaluated 45 total knees undergoing isolated tibial insert exchange. At minimum 2 years, 4 knees (9%) required revision. Significant improvement was seen in clinical outcomes questionnaires, but only 58% had clinical successful global WOMAC scores.
In summary, isolated liner exchange in the revision total knee setting has variable results. It can be successful but it is indeed a rare option and should be limited to cases where the total knee arthroplasty is both well fixed and well aligned.
