Abstract
Total knee arthroplasty has been demonstrated to provide durable results with excellent pain relief and improvement in function. Our institution has studied and published the longest follow-up of mobile bearing TKR, fixed bearing modular TKR, and unicompartmental replacement. Indeed these studies support the durability of the operation and the improvement in function and relief of pain. They, however, are not perfect. In tricompartmental replacement, up to 5 or 6% are revised for loosening and or wear and in unicompartmental replacement, up to 25% are revised for loosening. There are also one or two percent of cases revised for periprosthetic fracture and one or two percent for hematogenous infection. One must remember these cases were performed in patients of average age 71.
When one looks at our results in more active patients with osteoarthritis who are less than 55, the results are less spectacular with 15% revised at 10 to 15 years for loosening. We all hope that better polyethylene and better tibial tray locking mechanisms (in fixed bearing modular designs) will improve these results, but to predict there will be no failures is a “leap of faith”. Long-term follow-up of cemented TKA in patients under 55 where monolithic tibial trays were utilised have demonstrated better results at 20 years (92.3%) survivorship versus those where modular tibial trays (68%) were utilised. Long-term studies of cementless total knee replacement, especially in younger patients are needed to see if this approach provides better results.
