Understanding Stem Cell Injections for Knee Osteoarthritis

Researchers Review How Stem Cells May Help Arthritic Knees

Knee osteoarthritis affects millions of people worldwide and is expected to become the fourth leading cause of disability. This comprehensive review examined how stem cell injections work and what clinical studies show about their effectiveness. The researchers wanted to help doctors and patients understand what to realistically expect from these treatments.

Mesenchymal stem cells (MSCs) are special regenerative cells that can be harvested from your own body. They come primarily from bone marrow or fat tissue. These cells have the ability to reduce inflammation and support tissue repair. The review looked at how these cells are processed and delivered into knee joints.

Most Studies Show Pain Relief Lasting Up to Two Years

The review found encouraging results across multiple clinical studies. Most research reports significant improvements in both pain levels and knee function. These benefits were measured against patients' baseline symptoms. The positive effects lasted up to 24 months in many cases.

Patients typically showed improvement on standard pain scales. They also reported better ability to perform daily activities. The treatments appeared safe, with no major concerns raised across the studies examined.

Fat Tissue Offers an Accessible Source of Healing Cells

Fat tissue, also called adipose tissue, is one of the richest sources of regenerative cells in your body. Doctors can harvest it using minimally invasive procedures. The tissue can then be processed in different ways:

• Culture-expanded cells: Grown in a laboratory for several weeks to increase cell numbers

• Stromal vascular fraction (SVF): Processed immediately from fat tissue

• Micro-fragmented adipose tissue: Gently processed to preserve natural healing properties

Each approach has advantages. Same-day procedures like micro-fragmented fat are simpler and less costly. They also maintain the cells' natural environment, which may help them work better.

Your Own Tissue Means No Rejection Risk

Using your own cells (called autologous treatment) eliminates the risk of immune rejection. This is a significant advantage over treatments using donor tissue. Your body recognizes the cells as its own.

The review noted that stem cell treatments do not prevent future options. If the injection does not provide enough relief, patients can still pursue other treatments. This includes joint replacement surgery if eventually needed.

Current Research Has Important Limitations

While results are promising, the researchers identified weaknesses in existing studies. Only 14 percent of studies included a comparison group. This makes it harder to know if improvements came from the treatment or other factors. More than one-third of studies had fewer than ten patients.

The review could not determine:

• Which cell source works best (fat versus bone marrow)

• The ideal number of cells to inject

• How long benefits truly last

These questions need larger, well-designed studies to answer. The researchers called for more rigorous research with standard measurements and longer follow-up periods.

What This Means for Patients Considering Treatment

This review supports that stem cell injections are a reasonable option for knee osteoarthritis. The treatments appear safe and most patients experience meaningful improvement. Fat-derived treatments like Lipogems® offer the convenience of a same-day procedure using your own tissue.

However, patients should have realistic expectations. Current evidence is promising but not definitive. The best candidates may be younger patients with early-stage osteoarthritis. These individuals want to delay or avoid joint replacement surgery. Discussing your specific situation with a qualified physician will help determine if this treatment fits your needs.

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Source: Lopa et al., Knee Surgery, Sports Traumatology, Arthroscopy, 2018.