This Medication May Help People Avoid Knee Replacement Surgery, Study Finds
If you've been following the GLP-1 conversation, you already know these medications have come a long way from their original purpose. They started as diabetes drugs, then became widely recognized for weight loss, and now new research suggests their reach may extend to joint health in a way researchers are still working to fully understand.
The study analyzed data from tens of thousands of people with knee osteoarthritis and found that those taking GLP-1 medications were significantly less likely to need total knee replacement surgery over the following eight years. Knee osteoarthritis affects over 300 million people worldwide and is one of the leading causes of chronic pain and disability.
There are currently no approved treatments that can meaningfully slow the disease, which is part of why researchers are actively looking for options that might change that (like GLP-1s). Here's what you need to know.
About the study
Researchers looked at health records from adults diagnosed with knee osteoarthritis between 2010 and 2024, drawing from a large U.S.-based database of electronic health records.
They grouped patients by which type of GLP-1 medication they were taking (any GLP-1 drug, or just the newer ones like semaglutide and tirzepatide) and how long they had been on it (one year or three years).
To make the comparison fair, the team matched each GLP-1 user with a similar person not taking these medications, pairing them based on age, sex, weight-related conditions, and other health factors.
GLP-1 users were significantly less likely to need knee replacement surgery
Across every group and every follow-up time point, people taking GLP-1 medications were less likely to undergo knee replacement surgery than those who weren't. The biggest difference came from sustained use of the newer drugs.
Among people who used semaglutide or tirzepatide for three years, the risk of needing knee replacement surgery over eight years was about 28% lower compared to matched non-users. Even one year of use of any GLP-1 medication was associated with a 10% lower relative risk at eight years.
Overall? It appears the longer people stayed on treatment, the greater the reduction in risk.
Why the effect may go beyond weight loss
The study authors note that while weight loss and pain relief are well-established benefits of GLP-1 medications, the associations seen here suggest something more may be going on.
The study points to several other possible contributing factors.
- Reduced inflammation: Preclinical studies have shown that GLP-1 medications may suppress inflammatory signaling and slow cartilage breakdown within joint tissue
- Pain relief: GLP-1 receptors appear to be present in the nervous system, and these medications may influence chronic pain pathways, which could independently reduce the likelihood of pursuing surgery
- Potential cartilage protection: Emerging research suggests semaglutide may protect cartilage through metabolic changes within joint tissue, independent of weight loss, though this is still being studied
- Better metabolic health overall: GLP-1 medications may address underlying metabolic dysfunction (including blood sugar dysregulation and inflammation driven by excess fat tissue) that is increasingly recognized as a key driver of joint degeneration
The benefits of GLP-1s are extending beyond weight loss, and this study further indicates that these medications have wide-ranging effects on the musculoskeletal system (including on bone).
If you have knee osteoarthritis, here's what this means for you
GLP-1 medications are not currently approved to treat or prevent osteoarthritis, and any decision to use them should be made with a doctor based on your individual health situation. Osteoarthritis, especially in people with obesity, is increasingly understood as a metabolically active disease driven by systemic inflammation, blood sugar dysregulation, and excess fat tissue.
Addressing those underlying factors may be one of the most meaningful ways to support long-term joint function. And a GLP-1 may help.
The takeaway
This study found that people with knee osteoarthritis who used GLP-1 medications, particularly semaglutide and tirzepatide over three or more years, were significantly less likely to need total knee replacement surgery compared to similar patients not using these drugs. The stronger effects seen with longer use and newer formulations of the medication.
For now, the findings add to growing evidence that metabolic health and joint health are deeply connected, and that treating one may meaningfully support the other.