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Having multiple long-term conditions should not prevent people with osteoarthritis having hip replacements. New research found that the surgery improved their quality of life and complication rates were generally low. Despite this, the study found that fewer than half of those with hip osteoarthritis had hip replacement surgery.

Osteoarthritis is a common type of arthritis that causes pain and stiffness. In severe cases, hip replacement surgery is recommended. However, surgery might be delayed, or even ruled out, if the person has other existing health conditions. Such decisions are not based on evidence; the researchers say no previous research has explored whether people with multiple long-term conditions have worse outcomes than others after this procedure.

This study analysed the health records of 27,560 people aged 65 and over, who all had a diagnosis of hip osteoarthritis. Decisions on surgery were influenced by long-term conditions, the study found; the more long-term conditions people had, the less likely they were to have a hip replacement. Yet these people generally had good outcomes and benefitted from surgery.

The research highlights the importance of an evidence-based approach. The researchers hope their work will help inform doctors and patients about the relative risks and benefits of hip replacement surgery.

Further information on hip replacements is available on the NHS website.

What’s the issue?

People with osteoarthritis have joints that are painful, stiff, and sometimes swollen. This happens when the protective cartilage on the ends of bones breaks down. It most often affects the knees, hips and small joints of the hands and is the most common type of arthritis in the UK.

When symptoms are mild, they can be managed with regular exercise, weight management or with special devices to reduce the strain on joints during everyday activities. If symptoms get worse, people may need painkillers or a structured exercise plan with a physiotherapist.

In severe osteoarthritis, people can have surgery to completely replace the hip or other affected joint. Hip replacement surgery generally gives people a greater range of movement and reduces their pain.

People having hip replacements are 70 years old, on average. By this age, many have other long-term conditions, such as high blood pressure or diabetes, which might increase the risk of any surgery. Doctors may therefore be concerned about recommending hip replacement surgery for older people who have such conditions.

Researchers explored how multiple long-term conditions influence the likelihood and timing of hip-replacement surgery. They also looked at the impact of multiple long-term conditions on the outcomes of hip replacement surgery.

What’s new?

The researchers analysed GP health records from across the UK. They included data from 27,560 people aged 65 years and older. Participants had an average age of 75 years and most (62%) were women. All had a diagnosis of hip osteoarthritis in their records.

The team assessed participants' general health through the number of other conditions, and medications mentioned in their records, and the number of primary care consultations in the preceding 12 months. There is no single way to measure other conditions; the researchers assessed conditions using different approaches, including a measure of frailty.

Hospital records showed that fewer than half (40%) the participants underwent hip replacement surgery.

In the whole group, which included people with and without multiple long-term conditions, the study found:

  • people with more long-term conditions were less likely to have hip replacement surgery, even if they had moderate poor health, and the benefits of surgery outweighed the risks
  • neither age nor gender affected the rate of surgery, which suggested that surgery was withheld because of the long-term conditions the people had, and not these other factors
  • even people who were ‘mildly frail’ were less likely to have the surgery
  • most surgery took place 10 months after a diagnosis was added to GP records, but the more pre-existing long-term conditions a person had, the longer they waited.

In a group of 6682 people with hip osteoarthritis and multiple long-term conditions, the researchers looked at the outcomes of hip replacement surgery.

They found that:

  • regardless of pre-existing conditions, patients reported improved quality of life 6 months after surgery
  • other conditions weakly predicted risk of complications (such as a heart attack or wound infection) but the increases in risk were small
  • people with worse health before surgery were more likely to have complications afterwards, though the complication rates (3%) and death rates (1%) were low
  • people’s health before surgery did not influence how long they stayed in hospital; but those with worse health before surgery were twice as likely to be readmitted to hospital afterwards than the healthiest people in the study group.

The researchers concluded that, for most people, having multiple long-term conditions should not be a barrier to having hip-replacement surgery.

Why is this important?

Professionals and patients both raise concerns about hip-replacement surgery when people have other long-term conditions. This research provides evidence about the risks and benefits of hip-replacement surgery for this group of people.

It found that hip-replacement surgery improves quality of life regardless of someone’s other conditions. The surgery could improve some other conditions, such as depression, because of the improvement in pain. The team would like to follow people up for longer, to understand the longer-term impact of surgery in people with multiple long-term conditions.

The findings from this study show that healthcare professionals and patients should decide together on the benefits of surgery to them. They should discuss the risks, including of anaesthesia, and jointly come to a decision based on evidence.

The researchers say that, as long as the risk of having a general anaesthetic is not too high, having multiple long-term conditions should not be a barrier to hip surgery.

What’s next?

These results depend on the accuracy of primary care health records. If a diagnosis was included in the medical records some time after the first symptoms appeared, people may have been suffering with pain for longer than the records suggest.

People with multiple long-term conditions did not stay in hospital any longer than other people after surgery. It is possible that the length of stay could be influenced more by type of procedure. Surgery carried out under local anaesthetic might have shorter hospital stays than those carried out under general anaesthetic.

You may be interested to read

One of the papers this NIHR Alert is based on: Ferguson R, and others. Influence of pre-existing multimorbidity on receiving a hip arthroplasty: cohort study of 28 025 elderly subjects from UK primary care. BMJ Open 2021;11:e046713

Another paper this NIHR Alert is based on: Ferguson R, and others. Does pre-existing morbidity influences risks and benefits of total hip replacement for osteoarthritis: a prospective study of 6682 patients from linked national datasets in England. BMJ Open 2021;11:e046712


Funding: This study was funded by the NIHR Research for Patient Benefit programme.

Conflicts of Interest: The study authors declare no conflicts of interest.

Disclaimer: NIHR Alerts are not a substitute for professional medical advice. They provide information about research which is funded or supported by the NIHR. Please note that views expressed in NIHR Alerts are those of the author(s) and reviewer(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

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Study author

Many people with other health problems, and their surgeons, worry about the hazards of surgery in particular. What this research showed was that, even in this group, the risks of surgery are a little higher than in those who are perfectly healthy, but these risks are outweighed by the benefits of the operation.We are good at knowing how both drugs and surgery work in people with single conditions. But this is problematic as increasingly people in medical practice have multiple health conditions. This is especially so for people having hip replacement surgery because they are generally older.Our work is the first to show that, having taken into account the risks, this surgery is beneficial to the overall health of patients with multiple long-term conditions. For most people, these conditions should not be a barrier to having surgery. Surgery brought about improvements to their quality of life which had a big impact on how they felt about their other illnesses.We would like to see our results being used to help guide discussions between patients and their doctors about whether to go ahead with hip replacement surgery.Alan Silman, Professor of Musculoskeletal Health, University of Oxford 

British Geriatrics Society 

Hip osteoarthritis can be a hugely debilitating condition, particularly in older people, where it can lead to decreasing mobility, loss of independence and poor quality of life. Hip replacements can be transformative in this situation. As average age at surgery increases, it is much more likely that patients will have multiple long-term conditions, frailty or both. This research indicates that decisions about surgical treatment can be influenced by these factors, even in older people whose co-morbidity is modest and frailty mild.This study highlights the importance of accurately understanding the risks and benefits of hip replacements in people with multiple long-term conditions and frailty, when making decisions to operate. Specialists in peri-operative care of older people are experts in risk assessment and facilitating patient-centred decision-making. This process is vital to prevent restricted access of older people to surgery which can be life changing.Mark Baxter from the Falls and Bones Special Interest Group and David Shipway from the Peri-operative Care of Older People Undergoing Surgery Special Interest Group, the British Geriatrics Society (BGS) 

Specialist hip surgeon 

I have been in practice for over 20 years and these findings are very relevant to me. The study addresses an important area of potential healthcare inequality for older people with hip osteoarthritis. It is clear that a substantial number are denied surgery because of misconceptions about how their multiple long-term conditions might result in an adverse outcome.Hip replacement surgery can be life-changing, and the paper addresses important issues regarding people who might well benefit. Protocol-driven decisions are likely to prevent many from having effective treatment for their arthritis. If there is doubt about anyone’s suitability for surgery, then they should be referred for a specialist opinion.Jeremy Latham, Consultant Orthopaedic Surgeon, Nuffield Health Wessex Hospital, Southampton 


This paper will be of interest to health professionals who care for people with hip osteoarthritis. It is particularly relevant to those who work across the integrated care system to care for people before, during and after hip replacement surgery.This research enables clinicians to consider the potential influence of multiple long-term conditions and frailty on the length of time people wait for surgery. It increases our understanding of the impact of multiple long-term conditions on patient experience and outcomes. This could stimulate evaluation of service design, and new approaches to integrated working. It is a step towards enhanced care delivery and person-centred care.Jennie Walker, Principal lecturer for Health and Allied Professions, Nottingham Trent University 
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