From the Guidelines
Stem cell injections for knee pain or osteoarthritis are not currently recommended as a standard treatment due to limited evidence supporting their effectiveness. The most recent and highest quality study, published in 2021 1, suggests that there is insufficient evidence to support the use of stem cell injections in the treatment of hip and knee osteoarthritis. This study, which is a clinical practice guideline developed jointly by the VA and DoD, recommends against the use of stem cell injections due to the lack of quality evidence regarding their effectiveness and safety.
Key Points
- The procedure can be expensive (typically $3,000-$5,000 per injection) and is generally not covered by insurance due to its experimental status.
- Patients should be aware that the FDA has not approved stem cell treatments for knee osteoarthritis, and many clinics offering these services may make exaggerated claims about benefits.
- More established treatments with stronger evidence include physical therapy, weight management, appropriate pain medications, corticosteroid injections, hyaluronic acid injections, and ultimately knee replacement surgery for advanced cases.
- A 2022 study published in The Journal of the American Academy of Orthopaedic Surgeons 1 also supports the use of established treatments such as oral nonsteroidal anti-inflammatory drugs, acetaminophen, and intra-articular corticosteroid injections, but does not recommend stem cell injections.
Recommendations
- Patients considering stem cell therapy should discuss the limitations and potential risks with their healthcare provider.
- Healthcare providers should recommend established treatments with stronger evidence, such as physical therapy and weight management, before considering alternative treatments like stem cell injections.
- Further research is needed to determine the long-term effectiveness and safety of stem cell injections for knee osteoarthritis, as noted in the 2021 study 1.
From the Research
Effectiveness of Knee Stem Cell Injection
- Knee stem cell injection may slightly improve pain and function up to six months after treatment, as compared with placebo injection, with low-certainty evidence 2.
- The mean pain score was 1.2 points better with stem cell injection than with placebo injection, and the mean function score was 14.2 points better with stem cell injection than with placebo injection 2.
- However, the certainty of the evidence was downgraded due to indirectness, suspected publication bias, and imprecision 2.
Comparison with Other Treatments
- Stem cell therapy is certainly superior to traditional treatments in the conservative treatment of knee osteoarthritis, considerably reducing pain with no obvious additional side effects 3.
- Intra-articular injections, such as corticosteroids and hyaluronic acid, have been shown to reduce pain and improve function, but their benefits may be short-lived 4.
- Physical therapy and weight loss are also effective non-surgical treatment options for knee osteoarthritis, leading to significant improvements in pain and function 5, 6.
Safety and Adverse Events
- The potential harms associated with stem cell injection are uncertain, with very low event rates for serious adverse events 2.
- Serious adverse events were infrequently reported, but all invasive joint procedures, including injections, carry a small risk of septic arthritis 2.
- The risk of other important harms, including potential concerns related to the use of a therapy with the theoretical capacity to promote cell growth, or to the use of allogeneic cells, remains unknown 2.