Knee pain from osteoarthritis remains a major cause of disability and missed worked days. Conservative treatment is typically aimed at relieving pain and begins with anti-inflammatory medications, physical therapy and opioid pain medications. Injection therapy with corticosteroids and hyaluronic acid will often be used as the next line of treatment for knee cartilage repair. Surgical treatments such as arthroscopy, subchondral bone drilling and microfracture are often the next steps in the treatment cascade.
Share this post:
Unfortunately, many of these patients continue to progress and eventually undergo knee joint replacement surgery. Stem cell therapy is a minimally invasive procedure that has the potential to decrease inflammation, halt the progression of the arthritic damage, repair joint cartilage, and delay or avoid knee replacement surgery.
Articular Knee Cartilage Damage
Articular cartilage damage, especially when it affects the knee joint, remains a major clinical problem due to the poor intrinsic ability for this tissue to repair itself. The major function of joint cartilage is to allow for smooth gliding of joint surfaces and protect the surrounding bone from stress. This is key for being able to continue doing sports such as skiing. Articular cartilage allows the knee to absorb shock and loads up to 20 times the body weight.
The Impact of Osteoarthritis
Osteoarthritis is a chronic degenerative disorder that ultimately leads to a gradual deterioration of knee joint cartilage. Osteoarthritis may also be the result of a prior injury to the knee joint such as a fracture, tendon damage and ligament tears. This may lead to joint instability which can cause wear and tear to the articular cartilage. Arthritis can affect not only the cartilage but may lead to damage of the bone beneath the cartilage, the synovial lining to the joint, ligaments, tendons, and muscles.
Types of Stem Cells for Degenerative Knee Cartilage
Injection of progenitor cells, especially mesenchymal stem cells, has been shown to be a better strategy to repair degenerative cartilage than implantation of differentiated cells such as articular cartilage. Adult stem cells have a reliable potential to differentiate into cartilage, bone, fat or soft tissue. They also display the ability to home to areas of inflammation and degeneration, and to modify immune system activity that can favorably influence the surrounding cartilage in areas of damage.
Encouragingly, results of pre-clinical and clinical trials have provided initial evidence of efficacy and safety in the therapeutic use of mesenchymal stem cell therapies for the treatment of knee cartilage damage and osteoarthritis. Cell-based therapy has become a key focus of tissue engineering research focused on functional replacement of cartilage and meniscus regeneration.
A year long animal study has provided research that demonstrates that stem cell treatments provide structural regeneration with mechanical properties comparable with the native cartilage.
Stem Cell Extraction Methods
Adult stem cells can be extracted by minimally invasive methods from fat tissue and bone marrow.
- Bone marrow stem cells have a good potential for differentiation and the concentrated cells have numerous growth factors that aid in the cartilage formation process. Cell numbers in bone marrow unfortunately dramatically decrease as we age and are often ineffective in older patients.
- Fat derived stem cells show an enhanced ability to differentiate into cartilage and are found in dramatically higher numbers than seen in bone marrow. Not only are they typically 500-2000 times more abundant but they don’t decrease as we age. Fat derived cells have been shown to be successfully employed to target cartilage defects and improve osteoarthritis in patient studies. Fat derived adult stem cells have also demonstrated improved outcomes over bone marrow for cartilage repair.
Not all research is favorable to stem cell therapy at this time due to a wide variation in techniques and cell choice from discrepancies in treatment methods. Due to the many ways stem cell therapy is performed, we see that some variations are not as potent as others.
Supplement with PRP or Concentrated Placental Growth Factors
A minimally invasive procedure to harvest stem cells from both fat and bone marrow and inject the concentrated cells under image guidance can be performed in 2-3 hours. This procedure when supplemented with additional growth factors from platelet rich plasma or concentrated placental growth factors combines the best properties from each source.
Potential Treatment Results
Clinical outcomes from ongoing and previous studies are very encouraging, demonstrating the ability to improve pain and generate knee cartilage repair. Many patients have been able to avoid knee surgery as a results of advanced stem cell therapies – learn more about the results of a stem cell patient from Denver. Further studies will help to define specific cell and growth factor combinations to maximize cartilage regeneration.
For more of Dr. Brandt’s insight on stem cells for cartilage repair, as applied in treatment of severe low back pain, check out the part 2 of this series: stem cells for disc cartilage regeneration.