Common steroid injections used to treat arthritis may actually make the crippling condition worse, a study suggests.
Researchers found cortisone jabs are effective in treating pain – but can speed up the degeneration of joints.
The team looked at more than 450 osteoarthritis patients, which causes joints to become painful and stiff.
Boston University experts found six in every 100 people taking steroids, such as hydrocortisone, saw their arthritis get worse within a year.
They say the drug may damage cartilage within the joint and make it weaker and more susceptible to wearing down, which may leave patients needing knee or hip replacements.
A study by the University of Boston has found that cortisone shots may actually accelerate arthritis (file)
But they claim more research needs to be conducted to discover why the steroid causes further damage in some cases.
The scientists have called for more the potential dangers found in their study to be included in consent forms currently handed to patients.
At present, the document largely only warns of minor side-effects common with most injections – such as a risk of infection.
Lead author Dr Ali Guermazi and colleagues also recommend sufferers with less severe symptoms avoid getting the steroids.
Cortisone injections, which numb pain, are also popular in professional sports and are used to help athletes perform through agony.
But they are most commonly used to treat osteoarthritis, which strikes around up to eight million people in the UK and 31million in the US.
More than 70,000 people in the UK have at least one cortisone injection every year, but many have up to three.
Research suggests the procedure costs the NHS nearly £40million every year. The procedure was generally viewed as safe but patients are made to sign a consent form.
But the document largely only warns of side-effects common with most injections – such as a greater risk of infection.
Researchers from Boston University School of Medicine looked at 459 patients who had corticosteroid injections in their hip or knee at the hospital in 2018.
The participants were aged between 37 and 79. Scientists found that 36 patients (eight per cent) had complications down the line – 19 women and 17 men.
WHAT IS OSTEOARTHRITIS?
Osteoarthritis – sometimes called ‘wear and tear’ – is a condition that occurs when the surfaces within joints become damaged.
Around a third of people aged 45 years and over in the UK suffer from the condition. This equates to roughly 8.75 million people. At least 20 million are known to suffer in the US.
It is different to rheumatoid arthritis, a long-term illness in which the immune system causes the body to attack itself, causing painful, swollen and stiff joints.
Replacement joints are often necessary for osteoarthritis patients, because the joint has been worn down and causes agonising pain.
Thirty patients had the jab in their hip, while six had it in their knees. Twenty-six patients saw their osteoarthritis accelerate and worsen within a year.
Four patients (0.9 per cent) suffered stress fractures – a break in the bone caused by accumulative damage – on their hips or knees.
Three people (0.7 per cent) experienced rapid joint destruction which resulted in bone loss, while another three patients suffered complications with osteoarthritis.
Dr Guermazi, a professor in radiology, said: ‘We’ve been telling patients that even if these injections don’t relieve your pain, they’re not going to hurt you. But now we suspect that this is not necessarily the case.’
He called for consent forms to detail the new dangers found in his team’s research.
He added: ‘Physicians do not commonly tell patients about the possibility of joint collapse or subchondral insufficiency fractures [stress fractures] that may lead to earlier total hip or knee replacement.
‘This information should be part of the consent when you inject patients with intra-articular corticosteroids.’
The researchers recommend that patients receiving injections with little sign of osteoarthritis on an X-ray are carefully monitored – especially when the pain they experience is disproportionate to what’s visible on the scan.
These patients, they point out, are at greater risk of destructive arthritis after injections.
Most importantly, the team state that younger patients must be told of the potential consequences of an injection before they are given it.
The widespread use of corticosteroid injections – particularly in professional sport – means the potential of the study are enormous, Dr Guermazi believes.
He added: ‘Intra-articular joint injection of steroids is a very common treatment for osteoarthritis-related pain, but potential aggravation of pre-existing conditions or actual side effects in a subset of patients need to be explored further to better understand the risks associated with it.
‘What we wanted to do with our paper is to tell physicians and patients to be careful, because these injections are likely not as safe as we thought.’
Clinical spokesperson for Versus Arthritis, Professor Tonia Vincent said: ‘Caution needs to be applied when interpreting a study of this sort which is observational and is not a clinical trial.
‘More work needs to be done to establish whether there is a true link between intra articular steroid use and disease progression.’