Platelet Rich Plasma – Fountain of Youth?

Within 24 hours, the topic of platelet rich plasma came up twice. A friend of mine said that a nurse who he sees at his gym had suggested he might try Platelet Rich Plasma (PRP) for chronic pain following a torn biceps tendon and he wondered what I (mind you, a retired gastroenterologist) thought. That day in The Gazette, there was an article entitled “American Spine offers experimental pain fix.” Given that Lady Doc’s Corner Cafe is a site that strongly encourages exercise, I thought this a topic worthy of further discussion.

Platelet rich plasma is, and has been, used in a variety of settings both operative and outpatient. In the operative setting it is used to help promote more rapid healing of bone grafts and tissue flaps and there is a fair amount of literature supporting its use in this setting. Given this success, PRP is now being used in the outpatient arena of sports medicine where it is not FDA approved and it’s effectiveness has yet to be clearly established. Further discussion of this topic is the purpose of this blog.

Platelet rich plasma refers to a portion of one’s blood that has been spun down in a centrifuge. The centrifuge separates different parts of the blood from one another. A platelet is a component of blood that assists in clotting. Additionally, platelet rich plasma is felt to contain a multitude of growth factors and other proteins in high concentration which aid in tissue healing. The injection itself may promote repair through causing injury, hence the importance of studies that use a placebo controlled trial to be sure that saline (salt water), for instance, wouldn’t induce the same healing effect.

Let’s start with what is most important to most people. PRP is not covered by insurers, is considered experimental in the outpatient setting and may cost between $500-1500/treatment. Often 3 treatments are advised and may be painful at the time of delivery if they are not given in conjunction with a surgical procedure.

The plasma rich portion of the blood is injected directly into the injured site under ultrasound guidance in an office setting. It has been tried for a variety of conditions including: tendinopathy (diseased tendons such as Achilles injuries and tennis elbow), plantar fasciitis, and osteoarthritis. It is typically tried when recommended therapies have failed, before surgery is contemplated.

Unfortunately, aside from the accepted uses in the operating room, the facts become murky. Few studies have been placebo controlled, randomized, blinded studies with large numbers of patients enrolled getting PRP for solely one condition. Meta-analyses, in which a number of studies are combined, have shown insufficient evidence to support the use of PRP in soft tissue injuries (1). The results of individual trials vary.

One study, “Efficacy of PRP for Chronic Tennis Elbow” had promising results. It was a double blinded, prospective multicenter randomized controlled trial with a total of 230 patients who had suffered pain for longer than 3 months. At 12 weeks after injection (PRP vs saline) there was little difference. However, at 24 weeks the difference became significant, with 71.5% in the PRP group having less pain vs 56.1% with less pain after the placebo (2). Of note is that about 50% of patients who received ANY injection, whether saline or PRP, had some lasting relief of pain. The act of injecting or “dry needling” a tendon may in and of itself offer some relief of pain through triggering injury and then repair mechanisms.

However, in another study with 60 patients (3), no difference was found in pain, disability level or ultrasound appearance of the tendon as compared to those that received a saline injection or a steroid injection. Two small studies evaluating the effectiveness of PRP injection for rotator cuff tendinopathy (3) and Achilles tendinopathy (4) also showed no benefit.

PRP has also been injected into joints affected by osteoarthritis. Here there is literature that suggests it may be beneficial. In a study by Patel, S et al. (5) 78 patients were randomized to either receive a saline injection into their knees, a PRP injection or a series of 2 PRP injections. The study found that those who received the PRP injection benefitted, showing significant improvement in their WOMAC scores (a measure of pain, stiffness and physical function). This benefit diminished after 6 months. As well, 2 injections were not better than one and those with mild inflammation did better than those with more severe arthritis.

In The Gazette, PRP is compared to the fountain of youth. I find little in the way of quality studies to support this point of view. My concern is that in clinical practice it may be widely utilized for a variety of sports injuries despite scant data. So what advice should I give my friend? Although this treatment is relatively safe with little risk, I have advised against PRP injection at this time, especially for an injured biceps tendon for which I found no literature support. There does appear to be some evidence to suggest PRP’s use for chronic tennis elbow and osteoarthritis of the knee. My best advice: work with a knowledgeable trainer to prevent getting injured in the first place. Start slowly. The fountain of youth is hard to come by.

1. Moraes VY, Lenza M, Tamaoki MJ, et al. Platelet-rich therapies for musculoskeletal soft tissue injuries. Cochrane Database Syst Rev 2013; 12:CD010071.

2. Mishram AK, Skepnik NV, Edwards SG, et al. Efficacy of Platelet-Rich Plasma for Chronic Tennis Elbow A Double-Blind, Prospective, Multicenter, Randomized Controlled Trial of 230 Patients. Am J Sports Med 2014: 42 (2): 463-471

3. Bell KJ, Fulcher ML, Rowlands DS, Kerse N. Impact of autologous blood injections in treatment of mid-portion Achilles tendinopathy: double blind randomised controlled trial. BMJ 2013; 346:f2310.

4. Kesikburun S, Tan AK, Yilmaz B, et al. Platelet-rich plasma injections in the treatment of chronic rotator cuff tendinopathy: a randomized controlled trial with 1-year follow-up. Am J Sports Med 2013; 41:2609.

5. Patel S, Dhillon MS, Aggarwal S, et al. Treatment with platelet-rich plasma is more effective than placebo for knee osteoarthritis: a prospective, double-blind, randomized trial. Am J Sports Med 2013; 41:356.