The role of age, gender, area deprivation and living arrangements on knee surgery outcomes

Project aims

This project aimed to find out if there are inequalities in the success of replacement knee surgery, depending on gender, age and social factors.

What we did

We used data from the UK National Joint Registry data set, which collects information on most knee surgeries carried out in England. The Department of Health and Social Care also collects information from patients to assess the success of various operations.

People are sent a survey about their knee pain and function, both before and six months after their operation to measure how much they have improved. Information about their age, gender, whether they live alone and the area they live in is also collected. We combined all this information so we could analyse how much these social factors affect knee symptoms and the success of the operation.

What we found and what this means

We found that these social factors have a very small effect on the success of replacement knee surgery.

Younger and poorer patients were likely to have slightly less improvement after the operation compared to older and richer patients. Women and men had a very similar amount of improvement, but women tended to start off with worse symptoms before the operation.

What next?

It is reassuring that this study found very little social inequality in the outcomes of replacement knee surgery. But because there were differences in knee symptoms before the operation, there could be inequality in the sorts of people who go for the operation, or when they get it.

Our research also raises the question of whether these social factors affect who experiences complications, like infections, after surgery. A follow-up project will explore this further.