Both total and partial knee replacements deliver lasting benefits at 10 years

In 2019, the Total or Partial Knee Arthroplasty Trial (TOPKAT) study, led by researchers at NDORMS, found that after 5 years, partial knee replacement (PKR) showed similar, if not better, outcomes than total replacement (TKR).  But the research horizon was extended to ten years to study whether the longer-term quality of life outlook for patients could be assessed.

Now, with 10 years of data, researchers have found that patients who underwent PKR and TKR had similar long-term pain relief, function, and quality of life outcomes.

Chief investigator David Beard, Professor of Musculoskeletal Sciences at NDORMS said: ‘This is the first large, randomised trial to report 10-year outcomes for partial versus total knee replacement. With no significant difference seen in patient-reported knee function, satisfaction, re-operations, or revision rates between the two procedures at 10 years, we can now confidently say that both operations are effective and durable.’

The study involved a multidisciplinary team from NDORMS and the Aberdeen Centre for Evaluation at the University of Aberdeen, with support from the Oxford Surgical Intervention Trials Unit (SITU). It followed more than 500 patients across 27 NHS hospitals for 10 years. They were asked questions about knee pain and function, the economic cost of the treatment, and healthcare.

The trial found that:

• Both PKR and TKR provided excellent long-term pain relief and functional outcomes.
• No significant difference was seen in patient-reported knee function, satisfaction, re-operations, or revision rates between the two procedures at 10 years.
• Complication rates were lower with PKR, and importantly, PKR proved more cost-effective than TKR, delivering better quality-adjusted life years (QALYs) at lower overall cost to the NHS.
• The pre-existing concern over high revision rate for PKR was not demonstrated in this trial. Revisions between the two types of implant were very similar at 10 years. 

‘Outside of health economic considerations, there is no strong clinical evidence to select one type of implant over another.  However, because PKR is cheaper, has quicker recovery, and can be revised more easily, it may represent a better first-line surgical option for appropriately selected patients,’ said Prof Beard. ‘With over 300,000 knee replacements performed in the UK each year, mainly for osteoarthritis, these results will reassure surgeon’s that both procedures are valid so that they can offer the best outcomes for their patients.’

The study was funded by National Institute for Health and Care Research Health Technology Assessment Programme.