TKA is an abbreviation of 'total knee arthroplasty' - the replacement of the natural knee joint with manufactured components.

Page updated February 2024 by Dr Sheila Strover (Clinical Editor)

TKA - toal knee arthroplasty

This photograph of a total knee arthroplasty teaching model, shows the three common components of:

  • metal femoral component
  • plastic spacer
  • metal tibial component


What is the indication for a TKA?

The timing when an arthritis patient undergoes TKA is somewhat subjective. Some patients with advanced osteoarthritic joint damage may be happy to tolerate the pain and disability, while others may be impatient to improve their lifestyle and accept the fact that the procedure is an amputative one, despite the likelihood of a much improved quality of life.


  • Quote fro peer-reviewed paper:

    "Although many conservative treatment modalities are available for the management of mild-to-moderate OA, end-stage arthritis of the knee is best managed with total knee arthroplasty (TKA)"

    Citation: Feng JE, Novikov D, Anoushiravani AA, Schwarzkopf R. Total knee arthroplasty: improving outcomes with a multidisciplinary approach. J Multidiscip Healthc. 2018 Jan 25;11:63-73. doi: 10.2147/JMDH.S140550. PMID: 29416347; PMCID: PMC5790068.

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What is the composition of the metal and plastic in a TKA?

The metal components are usually manufactured, under very strict conditions, from titanium, cobalt-chromium or cobalt-chromium-molybdenum.

Titanium is able to bind to bone, and the contact surface with the bone is specially prepared to allow for such integration. The articular surface is very highly polished to allow smooth motion. Cobalt-chromium is a metal that is very resistant to corrosion. Different manufacturers choose different metals depending upon their designs.

The polyethylene used in any spacer is very resistant to abrasion, although with time some abrasion will occur and the spacer may need to be changed.

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What is the difference between TKA and TKR?

The terms are effectively interchangeable.

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How does one evaluate the outcome of a TKA?

A number of scoring systems have been developed to assess the outcome of a TKA -

  • Quote:

    "One of the factors most strongly associated with postoperative satisfaction is patient's expectations: unmet expectations result in dissatisfaction. Therefore, it is important for surgeons to reach an agreement with patients on the possible benefits and risks of TKA through extensive discussion and explanation before surgery"

    Citation: Choi YJ, Ra HJ. Patient Satisfaction after Total Knee Arthroplasty. Knee Surg Relat Res. 2016 Mar;28(1):1-15. doi: 10.5792/ksrr.2016.28.1.1. Epub 2016 Feb 29. PMID: 26955608; PMCID: PMC4779800.

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Forum discussions

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total knee arthroplasty
total knee replacement

Dr Sheila Strover (Editor)
BSc (Hons), MB BCh, MBA

See biography...