In all the focus over All-star point guard John Wall getting PRP this week, some media outlets- including myself- overlooked that his doctors were also recommending viscosupplementation at the same time. Maybe because it’s such a long word that begs explanation.
Viscosupplementation means supplementing the joint fluid in the knee, a fluid which is usually viscous but can become more thin and watery when the knee becomes degenerated. We often refer to them as ‘lubrication shots’ because of their mechanical effect of providing increased cushion and glide in the knee, but they may also have an anti-inflammatory effect on the joint and may help hydrate the cartilage. They are also commonly called ‘chicken shots’ because the molecule in our joint fluid- Hyaluronic Acid or HA- is also found in rooster combs and that is the source for many of the viscosupplement products. In patients who find relief from their knee arthritis by draining their joint fluid and replacing it with this synthetic fluid, insurance typically covers repeating the injections every six months. Hence it is also referred to as an oil change for the knee.
As common as PRP is becoming in the professional sports world to speed the healing of ligament and tendon injuries and stave off degeneration inside joints, viscosupplementation is rarely used in athletes. A recent study compared HA vs PRP in end-of-career soccer players and found that both helped the athletes’ pain, with no difference between the two groups at 12 months (Papalia, 2016). But as an in-season means of decreasing inflammation in the joint it is probably underutilized. The old treatment of cortisone shots has been mostly abandoned now that doctors realize that cortisone weakens tissues and blocks healing, so it makes sense to reduce inflammation in ways that support joint health.
It is upsetting how much of clinical practice norms are determined by insurance coverage rather than efficacy. Insurance typically covers the HA viscosupplements for arthritis, but not for general knee inflammation in younger active patients. We know that HA is less effective when the knee is more severely degenerated in the elderly, but because it is covered we often try it anyway. So HA is probably overutilized in severe arthritis, but underutilized in young active patients with inflamed joints. PRP is also underutilized despite its efficacy due to insurance guidelines that restrict access to conserve costs. Large studies are expensive, and with no pharmaceutical company expecting big payoffs (as PRP uses your own cells) there is limited ability to finance those studies. Hopefully these high-profile cases of top athletes using PRP and HA will help drive the conversation, highlighting their effectiveness and the disparity of access to these safe, effective treatments.
Many media outlets are characterizing PRP as ‘experimental,’ conflating insurance coverage with proof of efficacy. In fact, PRP has been in use for over 15 years and it’s predecessor, prolotherapy, has been around since the 1950’s. The modern evidence base is consistently positive regarding the ability of PRP to repair tendons, ligaments, and joints. A 2014 review that pooled the outcomes from available studies compared PRP vs HA and found benefit from both, but the PRP group to have superior effectiveness with a longer duration (Chang, PMR 2014). A 2017 randomized trial found similar results, saying that both HA and PRP were effective for arthritis to a similar degree, slightly favoring PRP (Cole, AJSM 2017). But this may raise a false choice that John Wall has brought to the forefront. HA and PRP both support a healthy joint, in different ways. In addition to the mechanical lubricating effect, the HA seems to stimulate the cells that give rise to cartilage. This would be via a different mechanism than PRP as the HA contains no growth factors. Studies are showing that PRP is actually synergistic with the hyaluronic acid viscosupplements, with better outcomes when the two are combined (Lana, Journal of Stem Cells and Regenerative Medicine, 2016). At our clinic in St Cloud, Minnesota, we will often follow up regenerative treatments (such as bone marrow stem cells or PRP) with a viscosupplement two months earlier or later to help support healthy cartilage. For the Wizards sake, I hope that John Wall sees the same benefits from this fascinating new treatment that so many of our patients do.
Comparative Effectiveness of Platelet-Rich Plasma Injections for Treating Knee Joint Cartilage Degenerative Pathology: A Systematic Review and Meta-Analysis, Chang et al, PMR 2014 http://www.archives-pmr.org/article/S0003-9993(13)01212-4/fulltext
J Biol Regul Homeost Agents. 2016 Oct-Dec;30(4 Suppl 1):17-23.
Comparing hybrid hyaluronic acid with PRP in end career athletes with degenerative cartilage lesions of the knee.
Am J Sports Med. 2017 Feb;45(2):339-346. doi: 10.1177/0363546516665809. Epub 2016 Oct 21.
Hyaluronic Acid Versus Platelet-Rich Plasma: A Prospective, Double-Blind Randomized Controlled Trial Comparing Clinical Outcomes and Effects on Intra-articular Biology for the Treatment of Knee Osteoarthritis
J Stem Cells Regen Med. 2016 Nov 29;12(2):69-78. eCollection 2016.
Randomized controlled trial comparing hyaluronic acid, platelet-rich plasma and the combination of both in the treatment of mild and moderate osteoarthritis of the knee.