I love to write about what I experience, so this weekend a question came across social media about using HGH for osteoarthritis. While this has been the subject of some interesting airline magazine advertising for years, this patient sent along an article for me to review. Hence, I thought it was time to visit this topic.
What Is HGH?
HGH stands for Human Growth Hormone (aka somatotropin or just “growth hormone). This is a protein found in our bodies that’s more prevalent when we’re young as it stimulates growth, cell reproduction, and cell regeneration. HGH also stimulates the production of IGF-1, so it’s involved in insulin and glucose metabolism. While it has been traditionally prescribed for kids with short stature to improve their adult height, in the last 1-2 decades, it has also been prescribed to aging patients with no other problems. The idea is that it will help keep them young and there may be some evolving science in its infancy on using HGH or it’s cousins as an anti-aging drug.
The History of Injecting using HGH for Arthritis
The practice of using HGH for arthritis can be mostly traced back to a Miami area physician, Allan Dunn, who states that he began using HGH for arthritis back in the 1960s on animals. Then in the late 90s he began to use this method in patients, which seems to involve many weekly injections of HGH into joints. This treatment came on my radar about a decade or more ago when I began to see before and after x-rays in in-flight magazines (which are becoming more of an endangered species these days due to in-flight iPads). Dr. Dunn claims that this method produces real hyaline cartilage and is the only arthritis treatment capable of regenerating joints. In fact, his website contains this statement, “IAGH IS THE ONLY PROCESS WHICH EMPLOYS REJUVENATION TO REGROW REAL JOINT CARTILAGE. REJUVENATION IS ABSOLUTELY ESSENTIAL TO REGENERATE REAL JOINT CARTILAGE AND WITHOUT REJUVENATION THE TISSUE WHICH GROWS IS A SCAR TISSUE CALLED FIBROCARTILAGE.” So let’s dig in to examine those claims.
The FDA Trial
Dr. Dunn’s website states, “After many years of research on laboratory animals to demonstrate the efficacy and safety of the IAGH method, Dr. Dunn, in 1998, started to treat patients with arthritis OF THE KNEE in an FDA approved study. Every patient who has come for IAGH treatment has moderate to advanced arthritis and they have been told they need a joint replacement.”. My perception after reading this was that perhaps there was an FDA approval for the use of HGH for osteoarthritis? However, I was pretty sure, as a physician, that I had never seen that announcement. It turns out that in his CV, Dr. Dunn explains that he grew frustrated with the FDA as he wanted to change the frequency of injections of HGH and that took a bunch of paperwork, so he began using HGH without FDA approval for joints (off-label).
The Animal Data on HGH for Osteoarthritis
All cartilage regeneration studies begin in animals. However, one of the problems with cartilage regeneration in animals is that it tends to be pretty easy to do. Meaning we have animal studies showing that you can regenerate cartilage with PRP, mesenchymal stem cells, juvenile chondrocytes, and various growth factors (1). The hard part is translating those effects into actual human patients.
So what’s out there? First up, I found a study in rabbits where the surgeons added HGH to microfracture (2). They found no benefit to adding HGH and some downsides. Lisa Fortier, now at Cornell, did a nice review article on the use of growth factors in cartilage repair which summarized various animal studies but left out HGH (3). I did find one recent study that compared HGH to Hyaluronic Acid and placebo (again in rabbits) and found better cartilage repair with HGH (4).
While there are likely other studies out there, my review the research on HGH for osteoarthritis using animal models wasn’t overwhelmingly positive. I also scoured Dr. Dunn’s website for papers that he may have published in this area but could find none in his CV. I also ran several PubMed searches using various combinations of “Dunn AR”, “osteoarthritis”, “growth hormone”, and “HGH”. I found one paper, which is a descriptive record of the observations of cartilage repair that Dr. Dunn made in rabbits who were injected with HGH (5).
The Human Data on HGH for Osteoarthritis
There are only a handful of papers published on humans where HGH for osteoarthritis was the treatment. For example, this paper where the physicians added HGH to PRP and compared it to PRP alone (6). The HGH+PRP group did better for the first month, but then by the second month, there was no difference between the groups. This then brings us to Dr. Dunn’s paper which I mentioned above had been sent by a patient, which I can’t find in the US National Library. Near as I can tell is that this was a conference presentation. In this presentation, Dr. Dunn claimed to have regrown cartilage in 93% of severely osteoarthritis ankles. What evidence was reported to back up this claim? Not MRI or any of the increasingly sophisticated ways of measuring cartilage regrowth available when the paper was published, but the width of the joint on x-rays, as measured by Dr. Dunn. Let’s dig into that claim.
Joint Space Width as a Metric for Cartilage Regrowth
This now brings us back full circle to the ads in the airline magazines showing before and after x-rays. The problem with using an x-ray to claim that you have regrown cartilage is that there are many things that can increase the joint width. To make sure you know what we’re talking about, you can’t see cartilage on an x-ray. All you can see is the bones. Hence, the only thing that will be observable on an x-ray if cartilage has regenerated is that the width of the joint will get bigger.
First, there are simple things that can make the width of a joint on x-ray bigger that have nothing to do with cartilage regrowth. For example, the angle that the x-ray is taken can have dramatic effects on this measurement. For example, see below where I altered the angle of the x-ray beam slightly while taking two x-rays of my knee. I was able to make my knee look like it had arthritis (smaller joint space width) or no arthritis. To see how that works, see my quick video below:
Other things can also impact the width of the joint. For example, the time of day that the x-ray was taken or whether the x-ray was taken weight-bearing or not. Because of all of this uncertainty, for many years, the only types of cartilage regrowth studies that generally get published have used MRI. We published several of these early on in our use of mesenchymal stem cells in knees (7). Since then even more sophisticated studies have been used including T2 mapping and dGEMRIC studies (8).
Even if you wanted to avoid using all of these sophisticated ways to measure cartilage regrowth and wanted to use the much less sophisticated joint space width on x-rays, an independent doctor or a team of doctors would be needed to measure that width. Meaning you would want at least one set of eyes on that measurement to make sure that what you were recording wasn’t an artifact of the doctor taking the measurement. Was that done here? Not as far as I can tell.
The upshot? Dr. Dunn makes some bold claims about cartilage regeneration with HGH. However, I am unable to find any research that backs up those bold claims. Perhaps one day that research will be produced, but right now we have much better data for things like stem cells or PRP and cartilage repair than we do HGH.
(1) Medvedeva EV, Grebenik EA, Gornostaeva SN, et al. Repair of Damaged Articular Cartilage: Current Approaches and Future Directions. Int J Mol Sci. 2018;19(8):2366. Published 2018 Aug 11. doi:10.3390/ijms19082366
(2) Danna NR, Beutel BG, Ramme AJ, Kirsch T, Kennedy OD, Strauss E. The Effect of Growth Hormone on Chondral Defect Repair. Cartilage. 2018;9(1):63–70. doi:10.1177/1947603516678973
(3) Fortier LA, Barker JU, Strauss EJ, McCarrel TM, Cole BJ. The role of growth factors in cartilage repair. Clin Orthop Relat Res. 2011;469(10):2706–2715. doi: 10.1007/s11999-011-1857-3\
(4) Lubis AMT, Wonggokusuma E, Marsetio AF. Intra-articular Recombinant Human Growth Hormone Injection Compared with Hyaluronic Acid and Placebo for an Osteoarthritis Model of New Zealand Rabbits. Knee Surg Relat Res. 2019;31(1):44–53. doi:10.5792/ksrr.18.062
(5) Dunn AR. Morphoangiogenesis: a unique action of growth hormone. Microvasc Res. 2002 May;63(3):295-303.
(6) Rahimzadeh P, Imani F, Faiz SH, et al. Adding Intra-Articular Growth Hormone to Platelet Rich Plasma under Ultrasound Guidance in Knee Osteoarthritis: A Comparative Double-Blind Clinical Trial. Anesth Pain Med. 2016;6(6):e41719. Published 2016 Oct 19. doi:10.5812/aapm.41719
(7) Centeno CJ, Busse D, Kisiday J, Keohan C, Freeman M, Karli D. Increased knee cartilage volume in degenerative joint disease using percutaneously implanted, autologous mesenchymal stem cells. Pain Physician. 2008 May-Jun;11(3):343-53. https://www.ncbi.nlm.nih.gov/pubmed/18523506
(8) Trattnig S, Winalski CS, Marlovits S, Jurvelin JS, Welsch GH, Potter HG. Magnetic Resonance Imaging of Cartilage Repair: A Review. Cartilage. 2011;2(1):5–26. doi: 10.1177/1947603509360209