PAPER 112: IS THE POTENTIAL UTILITY OF MODULAR TIBIAL TKA COMPONENTS REALIZED? A MINIMUM 15-YEAR FOLLOW-UP OF A MODULAR TIBIAL TRAY TKA CONSTRUCT

Abstract

Purpose: Few reports are available at minimum 15 year follow-up of cemented modular cruciate retaining TKA, especially where all polyethylene patella components were utilized. This paper addresses the questions “What is the durability of cemented modular cruciate retaining TKA with all polyethylene patella components at 15 years?” and “Did modular tibial trays demonstrate their utility in terms of the potential for less costly and less complex revisions?”

Method: 101 Press Fit Condylar TKA’s were performed consecutively over a 27 month interval and followed prospectively for a minimum of 15 years. The average age at surgery was 72 years. Clinical Knee Society scores, need for revision, radiographic evidence of loosening, and osteolysis were recorded. All patients were recalled at 5 year intervals.

Results: At minimum 15 year follow-up, 34 patients with 45 knees were living and 40 patients with 54 knees were deceased (one patient [2 knees] was lost to follow-up). 81% of living patients had 15 year radiographs. 6 knees were revised (all related to wear and osteolysis). Average Knee Society clinical scores only deteroriated from 92 points to 89 points between 10 and 15 years.

Conclusion: This cemented modular CR TKA performed well at 15 years with only 6% of knees requiring revision. All revisions occurred after 10 years and were related to wear and osteolysis. 2/3 of the revisions could be salvaged without tibial component revision in this closely followed series. Hopefully these results can be improved with better wear-resistant designs and better quality polyethylene. Especially into the second decade, patients with modular tibial tray TKA constructs should be closely followed to optimize their utility allowing less costly and less complex revisions in cases with polyethylene wear.