Thousands of patients are being denied hip and knee replacement surgeries by the NHS due to their weight, according to a newly released report, leaving many in significant discomfort.

For individuals suffering from severe arthritis, joint replacement surgeries are often the final option to alleviate intense pain, regain mobility, and return to normal daily activities.

Research conducted by Arthritis UK reveals that 31 out of 42 integrated care boards (ICBs) in England—the NHS entities tasked with coordinating local healthcare services—have implemented criteria that tie eligibility for joint replacement surgeries to a patient’s body mass index (BMI).

Among these boards, eight enforce rigid BMI limits that can completely bar overweight individuals from being considered for surgery.

An additional 23 boards either mandate or strongly promote weight loss as a prerequisite for surgery eligibility, while only 11 boards impose no BMI-related conditions.

The charity has highlighted how these varying policies have led to a “postcode lottery,” where a patient’s access to necessary treatment is largely determined by their location.

Deborah Alsina, chief executive of Arthritis UK, said: ‘People waiting for joint replacement surgery have often already spent months or years with their mobility in decline.

‘Joints in need of replacement are incredibly painful and severely limit people’s ability to exercise, which can lead to weight gain.

Joint replacements, most commonly of the hip or knee, are often the last resort for people with severe arthritis

‘It is counterproductive to deny surgery that could help people regain mobility and improve their health.’

The report found BMI policies vary widely across the country, with different cut-off points and requirements that can be unclear for patients and open to interpretation by clinicians.

Guidance from the National Institute for Health and Care Excellence says BMI alone should not be used to exclude patients from referral for surgery and that decisions should be made on an individual basis.

Experts from leading surgical bodies echoed those concerns.

Fergal Monsell, president of the British Orthopaedic Association, said: ‘Improving someone’s health before planned surgery is usually helpful.

‘However, losing weight is not always easy and may not significantly reduce the risks of surgery.

‘Waiting while trying to lose weight may leave patients in greater pain and with reduced fitness.’

Tim Mitchell, president of the Royal College of Surgeons of England, said: ‘BMI alone should not act as a barrier to surgery.

‘Surgical decisions must be made case by case, reflecting each patient’s individual circumstances.’

ICBs often defend BMI policies by pointing to evidence that obesity can raise the risk of complications, including infection and slower recovery after surgery.

They are also under pressure to manage waiting lists and limited NHS resources.

However, Arthritis UK said the restrictions may be applied too broadly, affecting patients who could still benefit greatly from surgery.

The warning comes as obesity rates continue to rise in the UK, with nearly two-thirds of adults overweight and more than a quarter living with obesity.

Obesity is linked to serious conditions including type 2 diabetes, heart disease and respiratory illness, and is estimated to cost the NHS more than £11 billion a year.

At the same time, some experts have questioned whether BMI is the best measure of health risk, arguing it does not take account of factors such as fat distribution.

Arthritis UK is calling for an end to policies that restrict access to joint replacement surgery based solely on BMI, urging a more consistent and patient-focused approach.

Campaigners warn that unless the rules change, thousands of patients will continue to suffer unnecessarily.