When a patient comes into our office and we have made a realistic determination that they are a bone marrow derived stem cell candidate, the patient will often ask, “How long does the  treatment last?” Most times I will have a good idea why they are asking the question. The reason is because nothing they have tried up until this point has been a long-lasting success for them. In going over a hip or knee osteoarthritis patient’s history for example, we will discover a medical history filled with treatments that in many instances did provide short-term benefit. You have probably had a few of these treatments yourself. Let’s go through the treatments.

Cortisone injections. Corticosteroids are powerful anti-inflammatory substances. They are not used to relieve pain, but rather, to reduce inflammation. Reducing inflammation can lessen a patient’s level of discomfort in the short-term. Numerous studies over the years, however, have demonstrated that there is a steep price to pay for that temporary relief of discomfort. The price of prolonged use of cortisone? Cortisone will eventually cause degenerative joint disease in the joints they are injected into. I explain this further is my article Systemic side-effects of cortisone injections.

Doses of anti-inflammatories. In the many years that we have treated patients with degenerative joint disease, there has always been the instance when a patient will ask us if they can continue with their anti-inflammatory medications. The answer is typically no. When the patient asks why? We have to remind them that regenerative medicine techniques like the ones we use, count on the beneficial aspects of inflammation. Inflammation is the way Nature heals. If we stop the inflammation, we stop the healing.

There is a steep price to pay for the short-term benefits of anti-inflammatory medications.

This is from the Journal of orthopaedic surgery, (1) and university hospitals in the United Kingdom, The doctors in this study compared the long-term safety of taking anti-inflammatory medications with the long-term safety of knee and hip replacements. They are measuring side effects including mortality.

  • Mortality was the highest for naproxen (Aleve, Moltrin) and lowest for total hip replacement.
  • Highest gastrointestinal complications were reported for diclofenac (Voltaren) and lowest for total knee replacement
  • Ibuprofen had the highest renal complications.
  • Celecoxib (Celebrex) had the highest cardiovascular risk

The “results of this study show that medical management of hip and knee osteoarthritis, particularly with non-steroidal anti-inflammatory drugs, may carry higher mortality compared to surgery.”

Hyaluronic injections. Many patients I see have had prior discussion with doctors about hyaluronic acid injections. These injections can provide a good amount of pain relief, temporarily. Hyaluronic acid is a naturally occurring substance that is a major component of the protective synovial fluid that surrounds the knee. In its natural form it is also a key component of wound healing. In its processed form used for injection purposes, hyaluronic acid is NOT a key healing component as attested to by suggestions and recommendations that these injections are stop gaps until knee replacement can be performed. Please see my article Stem cell treatments increase good hyaluronic acid levels in arthritic knees for the research.

So how long do stem cell therapy treatments last?

For each person that answer may be considerably different. An older person who remains active may have very long-lasting relief and never need future treatments beyond the initial treatments. People who have very physically demanding jobs or are high level, high endurance athletes who continue the activities that lead them to degenerative joint or spine disease in the first place may have to be given a different expectation of when they may need treatment again.

Now there is science to help us understand why stem cell therapy is considered a long-term treatment by some.

A 2016 study published in the journal Stem cell research & therapy (2) found that Human stems cells injected into a rat joint remained dynamically active for 10 weeks. In other words the stem cells were influencing healing (joint regeneration and cartilage protection) for 10 weeks after the injection. This does not mean that a stem cell treatment lasts for 10 weeks. What these researchers were suggesting is that the stem cells they were studying were continuously promoting healing for 10 weeks and enlisting native stem cells to continue on the work after the initial stem cells injected are used up or reach the end of their usefulness and die off. I explain this much further in my article Research: The number of native stem cells in an injured knee increases after injury.

How long do the treatments last? 24 months? 5 Years? A study where the knee kept getting better.

A study in the journal Experimental and therapeutic medicine (3) suggests “Stem Cell treatment in patients with knee osteoarthritis showed continual efficacy for 24 months compared with their pre-treatment condition.“ So here the stem cell therapy lasted at least 24 months. But what is amazing about this research is that the knee kept getting better and better and that the effectiveness of the stem cell treatment improved at 12 and 24 months compared with at 3 and 6 months. The research concludes: “(Stem cell) application ameliorated (relieved) the overall outcomes of patients with knee osteoarthritis, including pain relief and functional improvement from basal evaluations, particularly at 12 and 24 months after follow-up.”

In the International journal of rheumatic diseases, (4) doctors found at the end of the five-year follow-up that stem cell treated knees were still better than before treatment.

More recently, a January 2021 study (5) assessed nine random control trial studies to assess longer-term outcomes in patients with knee osteoarthritis. The combined outcome of this research suggested that patients with knee osteoarthritis had improvements in pain and function upwards of 24 months. Note that the study ended at the 24 month follow up. These patients may have had benefit well beyond this.

Summary – How long will stem cell therapy treatments last?

There are many answers to this question. The more realistic answers are:

The treatment will provide long-term relief in many patients. Who are these patients?

  • Patients who will allow the treatment to repair damage by following post-treatment guidelines for activity.
  • The person who does physically demanding work may need more than two or three treatments to achieve a more long-lasting effect.
  • Some people will require supplemental treatment perhaps a year or more later.

In our peer-reviewed published medical studies we demonstrate typic stem cell therapy treatments in our patients.

Please see my articles for these case histories:

In this video, Marc Darrow, MD, JD. is applying stem cell therapy to a patients knee.

Do you have questions? Ask Dr. Darrow

A leading provider of stem cell therapy, platelet rich plasma and prolotherapy

PHONE: (800) 300-9300 or 310-231-7000

Stem cell and PRP injections for musculoskeletal conditions are not FDA approved. We do not treat disease. We do not offer IV treatments. There are no guarantees that this treatment will help you. Prior to our treatment, seek advice from your medical physician. Neither Dr. Darrow, nor any associate, offer medical advice from this transmission. This information is offered for educational purposes only. The transmission of this information does not create a physician-patient relationship between you and Dr. Darrow or any associate. We do not guarantee the accuracy, completeness, usefulness or adequacy of any resource, information, product, or process available from this transmission. We cannot be responsible for the receipt of your email since spam filters and servers often block their receipt. If you have a medical issue, please call our office. If you have a medical emergency, please call 911.


1 Aweid O, Haider Z, Saed A, Kalairajah Y. Treatment modalities for hip and knee osteoarthritis: A systematic review of safety. Journal of Orthopaedic Surgery. 2018 Nov 8;26(3):2309499018808669.
2 Li M, Luo X, Lv X, et al. In vivo human adipose-derived mesenchymal stem cell tracking after intra-articular delivery in a rat osteoarthritis model. Stem Cell Research & Therapy. 2016;7:160. doi:10.1186/s13287-016-0420-2.
3 Cui G-H, Wang YY, Li C-J, Shi C-H, Wang W-S. Efficacy of mesenchymal stem cells in treating patients with osteoarthritis of the knee: A meta-analysis. Experimental and Therapeutic Medicine. 2016;12(5):3390-3400. doi:10.3892/etm.2016.3791.
4 Davatchi F, Sadeghi Abdollahi B, Mohyeddin M, Nikbin B. Mesenchymal Stem Cell Therapy for knee osteoarthritis: 5 years follow-up of three patients. Int. J. Rheum. Dis. 2015 May 20. doi: 10.1111/1756-185X.12670.
5 Qu H, Sun S. Efficacy of mesenchymal stromal cells for the treatment of knee osteoarthritis: a meta-analysis of randomized controlled trials. Journal of Orthopaedic Surgery and Research. 2021 Dec;16(1):1-0.—1417

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