Knee Replacement by Implanting a Cemented Total Knee Prosthesis

As far as primary replacement is concerned, about 90% of all knee prostheses are cemented . Recipients are usually elderly patients with arthrosis. 2% of knee implants are hybrids (a cemented tibial component and a cementless femoral component)2.

For a cemented TKR the implants comprise:

 

  • femoral components,
  • tibial inserts or bearings(cruciate sparing, or with "posterior stabilisation"),
  • tibial baseplates ("resurfacing" or with stem)
  • and patella replacement (posterior surface made of metal or polyethylene).
    Bone cement, a vacuum mixing system, pulse lavage, and pressurisation are also required.


The outcome is influenced by the selection of bone cement: the Swedish knee register points to the fact that deciding in favour of a cemented TKR reduces the revision risk1.


According to the Swedich register, the proportion of revisions amongst cemented and cementless tibial components in TKRs is approx. 11% and approx. 16%1 respectively. In the case of cemented implants the revision risk is lower. Aseptic loosening is the most frequent indication for revisions, accounting for 58%, followed by 18% for "pain" and approx. 14.7% for infections2.


Minimally invasive and/or quadriceps-sparing approaches can be used for the implantation of a cemented knee replacement. A cemented knee replacement can be subjected to loading immediately after the operation.



Literature
  1. 1) Ann. Report 2003; The Swedish Knee Arthroplasty Register, Dep. of Orthopaedics Lund University
    Hospital 2004.
  2. (2) Meulen J et al. National Joint Registry for England and Wales – 2nd Annual Report | September
    2005; The NJR Centre Harwell, England 2005, www.njrcentre.org.uk