Knee arthroplasty is a cornerstone procedure of orthopaedic surgery, commonly performed to alleviate the pain and mobility issues associated with conditions like osteoarthritis. The primary variations of this procedure are Total Knee Arthroplasty and Unicompartmental Knee Arthroplasty.
While both procedures are intended to improve patient quality of life, recent studies have revealed differences in revision rates and patient-reported outcomes. Here, we look at both procedures, and the findings of the latest study.
What is Total and Unicompartmental Knee Arthroplasty?
Total knee arthroplasty replaces the entire knee joint, while Unicompartmental knee arthroplasty replaces just a single compartment of the knee. The damaged joint is replaced with synthetic materials, and a total knee arthroplasty is a more invasive procedure, requiring a longer recovery process.
Unicompartmental Knee Arthroplasty is specifically designed to address osteoarthritis that is confined to a single compartment of the knee, typically the medial compartment. On the other hand, Total Knee Arthroplasty (TKA) serves as a comprehensive solution, used when osteoarthritis has affected all three compartments of the knee.
How do the two compare?
The main difference between Total and Unicompartmental Knee Arthroplasty lies in the scope of the procedure. Although Unicompartmental Knee Arthroplasty is a less invasive procedure and generally has a quicker recovery time, it has a higher revision rate compared to Total Knee Arthroplasty. However, this doesn’t necessarily indicate a lower success rate for the Unicompartmental Knee Arthroplasty procedure.
The revision of a Unicompartmental Knee Arthroplasty can be less technically demanding than a revision Total Knee Arthroplasty. For this reason, surgeons may be more willing to offer a revision to Unicompartmental Knee Arthroplasty patients experiencing poor functional outcomes.
According to one study, a smaller percentage of patients who had total knee replacements and weren’t satisfied with their results (a score of 25 or less), ended up needing a second surgery compared to those who had partial knee replacements. This was true at the 6-month mark (5.1% for TKA vs 19.6% for UKA), 5 years (4.3% for TKA vs 12.5% for UKA), and 10 years (6.4% for TKA vs 15.0% for UKA) after the initial surgery.
Those who had a partial knee replacement were also 2.5 times more likely to need a second surgery due to reasons that weren’t always clear. Issues like the replacement part moving out of place, or progression of their knee condition, compared to those who had a total knee replacement.
Choosing the best procedure
The procedure that is right for you will largely depend on your individual condition and lifestyle. The extent of the osteoarthritis, your age, health, and expectations from surgery, will all play a role in which procedure you should undergo.
Every patient is unique, and what works best for one person may not be the best choice for another. To find out which procedure is right for you, book an appointment with leading orthopaedic surgeon, Mr Jonathon Webb.