Mortality rates in the first 45-days following knee replacement surgery have fallen dramatically since 2003, according to a National Joint Registry for England, Wales and Northern Ireland (NJR) study led by the University of Bristol.
Published in The Lancet, a team of researchers have analysed NJR data on death after knee replacement and found that:
- The risk of dying after knee replacement surgery has almost halved from 0.37% in 2003 to 0.2% in 2011 (146 patients)
- Older men with illnesses such as liver, cardiac or renal disease are at the highest risk of death after knee surgery. As a result, doctors can take greater care with and provide careful counselling to these patients. For example, their recovery might be improved if they were cared for in high dependency units
- Use of agents to treat and prevent blood clots does not lower death rates after knee replacement their use should be re-evaluated to examine the risks and benefits
- Being overweight, but not obese, is associated with the lowest risk of death – even lower than those with normal weight. This challenges the concept of what is an ideal weight in this group of patients
- Partial knee replacements are associated with a lower risk of death than total knee replacements but patients and surgeons need to consider other factors before choosing the most appropriate procedure. These other important factors include revision/reoperation rates, risk of complication, readmission as well as relief from pain and poor mobility
Professor Ashley Blom from the University of Bristol who led the team that undertook this work on behalf of the National Joint Registry said: “It is excellent news the risk of death after both hip and knee replacement has fallen so dramatically since 2003. It is interesting that measures to decrease clot formation after knee replacement are not associated with a decrease in the risk of death.
“We have also shown an association between lower risk of death and being overweight, but not obese.
“It is not surprising that partial knee replacements are associated with a lower risk of death as they are smaller operations than replacing the entire knee.”
Partial knee replacement surgery should continue to be offered as a treatment option to patients.
Mary Cowern (pictured above), NJR patient representative who has undergone three knee surgeries for arthritis since 1996 said: “This research outlines key areas for conversation between a potential knee replacement patient and their surgeon. From my own experience, I know how valuable an open discussion is – it can really help you to understand the risks, benefits and what role you have to play in your own recovery.
Elaine Young, Director of operations for the National Joint Registry concluded: “The NJR is delighted to see these published papers. Not only do they highlight the importance of NJR data in research but the relevance of high quality, peer reviewed literature in influencing clinical practice and helping to improve patient outcomes for joint replacement surgery.”