This is a plain English summary of an original research article. The views expressed are those of the author(s) and reviewer(s) at the time of publication.
This study compared 2 different types of surgery for severe ankle osteoarthritis: total ankle replacement and ankle fusion. It showed that:
- both led to similar improvements in walking, standing and quality of life, and both were safe
- fixed bearing (but not mobile bearing) ankle replacements outperformed ankle fusion in a separate analysis
- total ankle replacement may be better value for money over the course of a person’s lifetime than ankle fusion.
The findings will improve shared decision-making for surgeons and people with ankle osteoarthritis, the researchers say.
For more information about osteoarthritis, visit the NHS website.
The issue: how does total ankle replacement compare with ankle fusion?
In osteoarthritis, the protective cartilage at the end of bones is damaged, and people have painful and stiff joints. Ankle osteoarthritis is common, and can cause major disability and reduced quality of life. People who have had a bad ankle sprain or fracture, and those with poorly controlled rheumatoid arthritis or other inflammatory arthritis, are most at risk.
Exercise, weight loss, physiotherapy and painkillers can help manage ankle osteoarthritis. When people have tried these unsuccessfully for 6 months or more, surgery might be recommended. More than 4000 people in the UK have surgery for ankle osteoarthritis each year.
The most common procedure is ankle fusion, which fixes the joint in a permanent position to relieve pain, and hence improves ability to walk. Increasingly, people are requesting a total ankle replacement, which restores ankle movement.
Before this study it was unclear which of these procedures was most effective for people with ankle osteoarthritis. This randomised controlled trial explored which approach is better and compared value for money for the NHS.
What’s new?
This real-world study included 282 people with ankle osteoarthritis from 17 UK hospitals. They were aged between 50 – 85 years and most (71%) were men. 138 participants had a total ankle replacement using different artificial joints (fixed or mobile). The other 144 had ankle fusion.
Before surgery, and 1 year afterwards, participants completed a questionnaire about their ability to walk and stand.
The study found:
- similar improvements in standing, walking and quality of life with total ankle replacement and ankle fusion, 1 year afterwards; however, the group who received fixed bearing implants (the most common total ankle replacement) reported greater improvements in standing and walking than others
- similar use of healthcare resources and medications 1 year after surgery in both groups
- serious side effects were similarly likely in both groups; 18% with total ankle replacement (wound healing problems and nerve injuries were more common), and 24% with ankle fusion (bones that did not knit and thromboembolic events such as blood clots were more common)
- total ankle replacements cost more (£9,491) than fusion (£7,218) over 1 year, but over a person’s lifetime ankle replacements may be more cost effective than ankle fusion; people who received a total ankle replacement needed less support from family and friends.
Why is this important?
This is the first randomised trial to compare the most common surgical procedures to treat ankle osteoarthritis. Both approaches were similarly effective and safe after 1 year. However, fixed bearing implants for total ankle replacements may improve walking and standing ability more than ankle fusion. Total ankle replacement may be more cost effective. The findings will allow clinicians and patients to make informed decisions about which surgery is right for them.
The most recent report from the UK National Joint Registry shows that the most common implant used in a total ankle replacement is a fixed bearing implant. Surgeons should be reassured by the study results since they show that this implant leads to better outcomes than mobile-bearing implants.
This was a pragmatic study, so surgeons were allowed to use whichever surgical implant or surgical technique they are most familiar with. As such it reflected the real world and means that the findings are more relevant to routine clinical practice. But it also means that more research is needed to examine whether different conditions could make a difference to outcomes.
The researchers say the findings represent early outcomes (up to one year) and so must be interpreted with some caution as the results may change with time.
What’s next?
The researchers plan to follow-up participants 2, 5 and 10 years after surgery, to see if the improvements in walking are maintained, and whether one group has better outcomes over the longer-term.
You may be interested to read
This is a summary of the TARVA study (total ankle replacement versus ankle arthrodesis): Goldberg A, and others. Total ankle replacement versus ankle arthrodesis for patients aged 50-85 years with end-stage ankle osteoarthritis: the TARVA RCT. Health Technology Assessment 2023; 27.
A summary of the TARVA study for patients.
A patient’s experience of a total ankle replacement surgery (video).
A video explaining the pros and cons of ankle replacement surgery and ankle fusion surgery.
Funding: This study was funded by the NIHR Health Technology Assessment programme.
Conflicts of Interest: Several of the study authors have received educational funding support from companies that produce orthopaedic implants. See paper for full details.
Disclaimer: Summaries on NIHR Evidence are not a substitute for professional medical advice. They provide information about research which is funded or supported by the NIHR. Please note that the views expressed are those of the author(s) and reviewer(s) at the time of publication. They do not necessarily reflect the views of the NHS, the NIHR or the Department of Health and Social Care.
