Knee pain caused by worn-down or damaged cartilage is one of the most common joint issues, particularly among older adults and individuals with sports-related injuries. Because cartilage does not heal well on its own, many patients seek alternatives to surgery, and stem cell therapy has become one of the most discussed options. But does it really help regenerate knee cartilage?
What Stem Cell Therapy Aims to Do
Stem cells have the unique ability to develop into different types of cells, including those that make up joint tissues. In knee treatments, doctors often use mesenchymal stem cells (MSCs) derived from bone marrow, fat tissue, or umbilical cord tissue.
These cells are injected into the knee joint and ligament attachments with the hope that they will:
- Reduce inflammation
- Slow down or reverse cartilage breakdown
- Promote tissue repair (cartilage, ligaments, tendons, and or bone).
- Improve overall joint function
Can Stem Cells Regenerate Knee Cartilage?
Research shows promising results. Stem cells can stimulate repair, improve the joint environment, and support the body’s natural healing processes. Some studies suggest mild to moderate cartilage thickening after treatment, especially in early-stage osteoarthritis.
However, it is important to understand:
- True, full cartilage regeneration is still limited, primarily by poor blood supply. Stem cells may help the body repair small areas of damage, but they do not consistently rebuild large or severely worn-out cartilage surfaces. They have been documented to increase cartilage regeneration.
- Results vary widely depending on age, severity of damage, practitioner’s expertise, and type of stem cells used.
- Many clinical trials are still ongoing, and stem cell therapy is not yet considered a guaranteed cure.
So while stem cell therapy can improve symptoms, reduce pain, and enhance mobility, complete cartilage restoration is not yet proven for every patient.
Who May Benefit Most?
Stem cell therapy tends to work better for:
- Early-stage osteoarthritis
- Mild to moderate cartilage damage
- Younger, active, otherwise healthy individuals
- Patients are trying to avoid or delay knee replacement surgery
For people with advanced, bone-on-bone arthritis, results are usually less impressive, although we still see significant improvement in terms of pain and function. If you’re 70 with really bad knees that you’ve been told are bone-on-bone, stem cells can definitely help, but they aren’t going to give you a 20 year old knee. When done properly, they can roll back the degeneration 10 to 15+ years.
Benefits Reported by Patients
Many patients report:
- Reduced pain
- Less stiffness
- Better mobility
- Improved quality of life
These improvements may come from reduced inflammation rather than actual cartilage regrowth, although cartilage regrowth has been confirmed in some.
Limitations and Considerations
Stem cell therapy for knee cartilage has several important limitations:
- It is not FDA-approved for cartilage regeneration as a standard treatment. Stem cells are only approved for certain types of cancer; everything else is considered “off label.”
- Results vary and cannot be guaranteed.
- Multiple sessions may be needed. In my experience, multiple sessions are necessary for an optimum outcome. Many stem cell providers inject whatever they are going to use all at once, placing all of the solution in the joint space. It still works pretty well, but I find that splitting the treatment up into 6 sessions works much better. Additionally, the medial and lateral collateral ligament attachment sites should also be treated to help strengthen the entire joint.
- The cost can be high and is not covered by insurance. A typical cost ranges from 6,000 to 9,000 dollars. The main variable is how much regenerative solution is used, stem cells, and/or exosomes.
Is It Safe?
Studies show that stem cell injections are generally quite safe when performed by trained specialists. As with any new treatment, many providers are not highly trained in giving injections.
Risks may include:
- Temporary pain or swelling
- Infection
- No improvement in symptoms
- Extremely rare immune or tissue reactions
Conclusion
Stem cell therapy may help the knee heal, reduce pain, and improve function, especially in the early stages of cartilage damage. True, complete cartilage regeneration remains limited, and more long-term scientific evidence is needed.
For now, stem cell therapy is a potential primary and supportive treatment. No one can guarantee results with stem cell therapy or any other treatment, including knee replacement.
Interestingly, about 25% of our knee patients have had knee replacement on one knee and simply don’t want to go through that with the other one.