Partial knee replacement is safer than total knee replacement but requires more revision

Partial knee replacement surgery is safer than total knee replacement according to a large UK study published in The Lancet.
Participants (from the National Joint Registry for England and Wales) comprised 25,334 people who had partial knee replacements and 75,996 who had total knee replacements. The data showed:

• The risk of life-threatening complications from knee replacement surgery is very small, but people who have total knee replacement are four times more likely to die in the first month after surgery compared to those who have partial knee replacement and 15% more likely to die in the first eight years.
• People who have total joint replacement are twice as likely to have a heart attack, thrombosis or deep infection, three times as likely to have a stroke and four times as likely to need blood transfusions, compared to those having partial replacement.
• After total knee replacement, people stay in hospital longer and have a higher chance of being readmitted or requiring a re-operation during the first year.
• People who have a partial knee replacement are 40% more likely to have a re-operation during the first eight years after the replacement, than those who had a total knee replacement.

“Up to half of knees that require replacement, usually because of severe osteoarthritis, can be treated with either partial or total replacements,” explains a spokesperson from Arthritis Research UK. “With partial replacements… only the damaged parts of the knee are replaced and the remaining surfaces and all the ligaments are preserved.”
At the moment, only about 7,000 partial knee replacements take place every year in the UK because of the higher revision rate.
Partial knee replacements are often offered to younger people who, because of their higher activity levels, have increased failure rates. But total knee replacement is a common surgical procedure, with over 76,000 performed each year in the UK; only 5% of patients need revision surgery over a 10-year period.
“The risks have been assessed in this study, which found that partial knees have fewer complications and deaths; however they do lead to more re-operations,” explains Prof David Murray, who led the research. “Patients will however be more concerned to avoid death and major complications, such as heart attack or stroke, than reoperations.
“To put the risks in perspective, if 100 patients had a partial knee rather than a total knee replacement there would be one fewer death and three more re-operations in the first four years after surgery.
“Oatients who have severe arthritis are very immobile and therefor tend to be unfit. Joint replacement overall, by making patients more mobile and fit tends to save lives.”
Alex Liddle, who ran the study, comments:
“Partial and total knee replacements are both successful treatments and a large proportion of patients with end-stage knee osteoarthritis are suitable for either. Both have advantages and disadvantages, and the choice of which procedure to offer will depend on the requirements and expectations of individual patient.”
Click here to read the original research.