Weight loss medications, including popular drugs like Ozempic and Wegovy, could significantly reduce the need for knee replacement surgery for some patients, new research suggests.
This offers a potential breakthrough for one of the most common pre-planned operations in the UK, where over 110,000 total knee replacements are performed annually.
The findings indicate that a substantial number of these surgeries, particularly among individuals suffering from osteoarthritis, might be avoided through the use of these drugs.
Experts from the University of Maryland School of Medicine in the US led the study, which focused on glucagon-like peptide 1 receptor agonists (GLP-1s). These medications, which include Mounjaro, Ozempic, and Wegovy, are primarily prescribed for type 2 diabetes and obesity.
While GLP-1s have previously been linked to a reduction in knee osteoarthritis pain, researchers noted that no studies had yet explored their potential to lower the risk of knee replacement surgery itself.
To address this, the team analysed data from a global database, examining patients diagnosed with knee osteoarthritis between 2010 and 2024. They tracked whether these individuals were taking GLP-1 drugs and compared this information against the need for total knee replacement surgery, assessed at one, three, five, and eight years post-diagnosis.
The study revealed a "significantly lower incidence" of total knee replacements among those who had taken GLP-1s. This protective effect appeared more pronounced with longer treatment durations and among patients using newer versions of the drugs, such as semaglutide (found in Ozempic or Wegovy) or tirzepatide (Mounjaro).
Researchers estimated that if patients in the US took newer GLP-1s for three years, a one-year "absolute risk reduction of 1.44%" could lead to 14,400 fewer knee replacements each year in the country alone.
The study authors suggested their findings point to "potential disease modifying activity beyond weight loss alone," though they stressed the need for confirmation through further trials.
They wrote in the journal Regional Anesthesia and Pain Medicine: "These findings suggest that GLP- 1 RAs, particularly newer agents used over sustained durations, may represent a meaningful complementary strategy within non- surgical knee OA management for eligible patients with concurrent obesity or metabolic disease."
They added: "In this large, multicentre, real-world cohort study, GLP- 1 RA use was associated with a significantly reduced long term risk of TKA (total knee arthroplasty) in patients with knee OA, with effects that were greater with longer treatment duration and newer generation agents.
“These duration and agent dependent associations are consistent with potential disease modifying activity beyond weight loss alone, although prospective trials are needed to establish causality and define optimal treatment targets."
Commenting on the research, Professor Lucy Donaldson, director of research at Arthritis UK, described the study as "encouraging."
She stated: "This is an encouraging study which suggests that people with knee osteoarthritis who were taking weight loss medications were less likely to need knee replacement surgery compared to those not taking these medicines. 70% of UK adults living with long-term musculoskeletal conditions are classified as overweight or obese.
“Maintaining a healthy weight can play a vital role in managing osteoarthritis, particularly in weight-bearing joints such as the knees and hips. However, we know arthritis can lead to difficulties in staying mobile and active.
“For those able, even a small amount of weight loss can improve symptoms and sometimes slow the progression of OA. Research like this is helping us better understand the potential impact of weight loss medications, including whether they could help some people with osteoarthritis avoid or delay the need for joint replacement surgery."
The study highlights the growing potential of weight loss medications not just for managing obesity and diabetes, but also for their broader impact on musculoskeletal health, potentially offering a new avenue for preventing or delaying invasive surgical procedures.
