PT Classroom - Rehabilitation Specific Concerns with Pro-Inflammatory Injections ׀ by Bryant J. Walrod, MD

Many of you may have seen or heard the recent press conference from Tiger Woods at the Masters. He was asked about Performance Enhancing Drugs (PEDs). He stated that he never took PEDs but that he did undergo Platelet Rich Plasma Therapy (PRP) injections into both his Lateral Collateral Ligament and recently a poorly healing Achilles Tendon. He credited PRP with his quicker return to play. Many of you may have heard of pro-inflammatory injections like prolotherapy and PRP. I will try to explain a little bit about each of them here ending with an emphasis on rehabilitation specific concerns.

Often the terms tendinitis, tendinopathy and tendinosis are used incorrectly and interchangeably. The term tendinopathy refers to an abnormal tendon. Tendinitis is the term that describes an acutely inflamed tendon. Tendinosis describes a poorly healing tendon with no inflammation. These terms matter because an accurate description will lead to more appropriate and effective treatment. For example, why would a practitioner inject an anti-inflammatory like cortisone into or around a non-inflamed, poorly healing tendon?

Nirschl demonstrated in a landmark study that chronic non-healing tendon issues are devoid of inflammatory cells, but rather contain poorly healing and disordered tendon tissue. He did a biopsy of the Extensor Carpi Radialis Brevis origin in patients with chronic lateral epicondylitis. Microscopic evaluation revealed an absence of inflammation but rather collagen disarray. He coined the term, “angiofibroblastic degeneration". I like to think of tendinoses as chronic poorly healing tissues with disorganization, chronic micro-tearing and mal-adaptive scarring.

These and other studies lead us to re-evaluate how we are treating chronic non-healing tendinopathies that are truly not inflamed. Practitioners began invoking such pro-inflammatory treatments like: Platelet Rich Plasma injection, autologous blood injections, osmotic proliferent injections (prolotherapy), dry needling and topical nitric oxide application.

Prolotherapy refers to the injection of a pro-inflammatory substance into an area or poorly healing chronic tendinosis. I typically use D50 or Dextrose as an osmotic proliferent to cause local inflammation. This local irritation and inflammation will cause an increase in fibroblasts and proper collagen formation. It also irritates to allow for proper healing and interrupts the maladaptive cycle of poor and disordered healing. Studies have demonstrated an increase in deposition of new collagen after prolotherapy treatment. This new collagen shrinks and then tightens the tissue that was injected and makes it stronger. In fact, histologic studies also demonstrate an increase in mass and thickness of ligaments treated with prolotherapy.

Another potential treatment option is Platelet Rich Plasma (PRP) therapy injections. These have gained widespread media exposure from famous athletes like Tiger Woods and Hines Ward touting its effectiveness. Platelets are a component of blood that assist with clotting but they are also rich in healing factors. By definition PRP is autologous (or one’s own blood) with concentrations of platelets above baseline. Platelets are responsible for hemostasis, construction of new connective tissue, revascularization. They posses many growth and healing factors. The process is pretty simple. I draw the patient’s own blood and then put it into a centrifuge for 15 minutes. This process separates the blood into different components based upon their density. I then draw off only the platelets and then inject them back into the area of the poorly healing tendinoses. This stimulates the body’s own inflammatory response in an environment rich in growth and healing factors.

There is variation with respect to how many prolotherapy or PRP injections are necessary. Unfortunately, most of the information is anecdotal with no controlled studies demonstrating one specific protocol over another. I typically use 3 injections of Dextrose every 3 weeks for prolotherapy and just one injection of PRP. You will see wide variations in this in the literature. I have had excellent success in treating chronic, difficult to treat tendinoses with these protocols.

With respect to rehabilitation after a pro-inflammatory injection, I like to stress eccentric exercises. In the 3-5 days after an injection, I will give the patient a brace to wear to prevent excessive use of the involved area. Then, I have the patient begin formal Physical Therapy. The first week is limited to eccentric range of motion exercises only. In weeks 2 and 3, we typically progress to eccentric strengthening. If the patient is receiving multiple injections, this protocol would restart after the next injection. Again, this is anecdotal and there are no controlled studies promoting one protocol over another. My patients have experienced excellent results with adherence to this regimen.

Additionally, I tell the patients to avoid any anti-inflammatory treatments while undergoing PRP or prolotherapy. This includes avoiding medications like Non Steroidal Anti-Inflammatory Drugs (NSAIDS) and also modalities that infuse local anti-inflammatory medications like phonophoresis.

There is still much to learn about pro-inflammatory injections. We need to clarify appropriate dosing regimens and post-procedure protocols; however, I am confident that there is a place for them in augmenting treatment of chronic non-healing tendinoses. My frustrated patients with difficult to treat chronic tendon issues would completely agree.