Laurie's Blogs.


Sep 2021

PRP – What’s new in HUMAN research?

Laurie Edge-Hughes, BScPT, MAnimSt, CAFCI, CCRT

I think it’s important to keep an eye on human research.  Realistically, human research receives more funding, there are more practitioners in the field of human research, and I believe we can learn a lot from seeing what’s being done there, in order to guide the thoughts, practices, and future research on the animal side.  So, let’s look at a handful of review papers.


1.  Jayaram P, Kang GE, Heldt BL, et al. Novel assessment of leukocyte-rich platelet rich plasma on functional and patient reported outcomes in knee osteoarthritis: a pilot study. Regenerative Medicine, 2021. 


This group of researchers incorporated wearable technology to objectively assess functional outcomes such as Timed Up and Go test (TUG), in addition to patient-reported outcomes to comprehensively evaluate the efficacy of one PRP injection for knee OA.  They found that a single injection of PRP into the knee does significantly improve functional mobility, pain and quality of life at six weeks.


So, maybe we can do the same with a ‘Fitbit’, ‘Apple Watch’, or GPS monitor attached to a dog to quantify movement after rehab interventions as well!  Throwing that out there!


2.  Belk JW, Kraeutler MJ, Houck DA, Goodrich JA, Dragoo JL, McCarty EC. Platelet-Rich Plasma Versus Hyaluronic Acid for Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Am J Sports Med. 2021 Jan;49(1):249-260.


This is a review study where the research team found 6 studies for inclusion.  They concluded that patients undergoing treatment for knee OA with PRP can be expected to experience improved clinical outcomes when compared with HA. Additionally, leukocyte-poor PRP may be a superior line of treatment for knee OA over leukocyte-rich PRP.

I think in the veterinary world… it might also come down to cost.  PRP seems to be a costlier intervention versus hyaluronic acid.  So, that is a factor that might come into the decision-making process as well.



3.  Karasavvidis T, Totlis T, Gilat R, Cole BJ. Platelet-Rich Plasma Combined With Hyaluronic Acid Improves Pain and Function Compared With Hyaluronic Acid Alone in Knee Osteoarthritis: A Systematic Review and Meta-analysis. Arthroscopy. 2021 Apr;37(4):1277-1287.e1. 


What about HA and PRP together?  This review & meta-anaylsis was based on 4 studies comprising 377 patients.


Symptomatic patients with knee OA who were injected with a combination of PRP and HA demonstrated greater improvement in pain and function compared with patients who received HA injections only, as assessed by 3-, 6-, and 12-month visual analog scale scores and 12-month WOMAC physical function and stiffness scores.



4.  Nauwelaers AK, Van Oost L, Peers K. Evidence for the use of PRP in chronic midsubstance Achilles tendinopathy: A systematic review with meta-analysis. Foot Ankle Surg. 2021 Jul;27(5):486-495. 


Here’s a review paper that I think needs to be acknowledged in the animal health side.  PRP for Achilles’ tendons – yes or no?  

This review sifted through 367 studies, to select only 4 RCTs that met inclusion criterion, but represented 170 patients that could be used for meta-analysis.  

Let’s cut to the chase!  Results showed no difference in clinical outcome between the PRP and placebo group at different points in time using the VISA-A score as outcome parameter at 3 months, 6 months, or 12 months. 



5.  Giovannetti de Sanctis E, Franceschetti E, De Dona F, Palumbo A, Paciotti M, Franceschi F. The Efficacy of Injections for Partial Rotator Cuff Tears: A Systematic Review. J Clin Med. 2020 Dec 25;10(1):51. 


This study, however made a different conclusion in regards to Rotator Cuff Tears.  They reviewed 9 studies that compared corticosteroid injections to PRP (or other drugs).  


Their conclusions? 

None of the techniques prevail indisputably on the others. Anyway, the treatment of partial rotator cuff tears with PRP injections seems to lead to significantly better outcomes in terms of pain and shoulder function in long term follow up. Whereas in short and medium term follow up, PRP injections was superior only in terms of shoulder function.


Is this a contrary finding?  Not so much… because for years we have known that corticosteroid injections into tendons can weaken them.  As a ‘human’ physiotherapist, I wouldn’t recommend a steroid injection into a tendon.  So, is this a fair comparison?  PRP was better than something that should be done.  Hmmm.



6.  Irby A, Gutierrez J, Chamberlin C, Thomas SJ, Rosen AB. Clinical management of tendinopathy: A systematic review of systematic reviews evaluating the effectiveness of tendinopathy treatments. Scand J Med Sci Sports. 2020 Oct;30(10):1810-1826. 


One more!  This systematic review of systematic reviews was conducted to determine the ability of therapeutic interventions to improve pain and dysfunction in patients with tendinopathy regardless of type or location.  The final review, reviewed 25 systematic reviews!  


Here’s the listing of what they found:
Eccentric exercises were the most common and consistently effective treatment for tendinopathy across systematic reviews. Low-level laser therapy and extracorporeal shockwave therapy demonstrated moderate effectiveness, while platelet-rich plasma injections demonstrated inconclusive evidence on their ability to decrease tendinopathy-related pain and improve function. Corticosteroids also showed some effectiveness for short-term pain, but for the long-term use deemed ineffective and at times contraindicated. Regarding surgical options, minimally invasive procedures were more effective compared to open surgical interventions.



The wrap up!


All in all, I would feel comfortable in coaching a client who was thinking of osteoarthritis interventions for their dog towards PRP and/or hyaluronic acid injections.  However, I’d want to steer them away from PRP (or cortisone) injections for a tendon issue in favour of the rehab therapies that we could provide instead.


I hope this helps you in your thought processing this week!


Cheers!  Laurie