Platelet-rich plasma (PRP) therapy was first introduced in the 1970s and has been used in many medical specialties, including orthopedic surgery, plastic surgery, sports medicine, wound care, and pain management, since the 1990s. There has been a wide variety of recent literature about platelet rich plasma therapy, or PRP therapy, being used to treat several types of common sports injuries, such as skeletal fractures, torn ligaments and tendons, strained muscles, sprained knees and other joints, and other chronic tendon injuries. This relatively new treatment has been known to promote the regeneration of soft tissue and healing within the body without the risks and extended recovery time often associated with surgery.
PRP therapy involves the injection of concentrated platelets, autologous growth factors, and secretory proteins into the region of treatment. PRP has been used for numerous conditions. In interventional pain management, it is commonly used for acute and chronic conditions such as tendinopathy, tendonosis, muscle strain, muscle fibrosis, ligamentous injury, arthritis, arthrofibrosis, articular cartilage defects, meniscal injury, and chronic synovitis or joint inflammation. The PRP concentrate is made from the patient’s own blood. After the blood is centrifuged, it separates into the plasma (top coat), the platelets and white blood cells (buffy coat or middle layer), and the red blood cells (bottom layer). The middle layer contains a platelet concentration of at least 1 million platelets/uL (normal range: 150,000—350,000 platelets/uL) and a 5- to 8-fold increase in growth factor concentrations.. Giusti et al examined the optimal concentration of platelets for promoting angiogenesis in human endothelial cells and found 1.5 million platelets/uL to be the optimal concentration. With the system used in our practice, 30-60 cc of blood will yield approximately 3-10 cc of concentrate. Platelets synthesize and release more than 1,100 biologically active proteins, including those that promote tissue regeneration. PRP is thought to enhance the recruitment, proliferation, and differentiation of cells involved in tissue regeneration to promote healing.
Over the past decade, numerous published studies involving human subjects have emerged investigating the use of PRP for conditions such as lateral epicondylitis, patellar tendinopathy, Achilles tendinopathy, rotator cuff tendinopathy, rotator cuff tears, medial collateral ligament and anterior cruciate ligament tears, and osteoarthritis of the knee. Although most of the studies examined small populations, there has been a wide variety of recent literature about platelet rich plasma therapy, or PRP therapy, being used to treat several types of common sports injuries, such as skeletal fractures, torn ligaments and tendons, strained muscles, sprained knees and other joints, and other chronic tendon injuries. This relatively new treatment has been known to promote the regeneration of soft tissue and healing within the body without the risks and extended recovery time often associated with surgery.
WHAT DOES RESEARCH SAY ABOUT PRP THERAPY?
Research concerning the clinical validity of PRP therapy is currently being conducted; however, there have been several recent studies that have produced substantial evidence regarding the positive effects of platelet rich plasma therapy. One recent investigation, published in the International Journal of Neuroscience, revealed promising results of PRP injections for the treatment of peripheral nerve regeneration following nerve injuries.
Other continuing studies regarding platelet rich plasma are targeted on the effectiveness of this therapy in treating conditions such as:
According to current research, factors that may influence the effectiveness of PRP treatment include the overall health of the patient, the particular area of the body that is being treated, and whether the injury is acute or chronic. Although the results concerning the association of these factors and the success of platelet rich therapy are inconclusive at this time, researchers believe that additional studies concerning these topics are needed.
A 2016 study from the University of Alberta also reported improved pain and mobility after using PRP injections. While it was a smaller study, the results showed clinical relevancy and could push for more research into PRP therapy.
Doug Gross, author on the study and interim chair of physical therapy at the Faculty of Rehabilitation Medicine, stated that:
“Based on MRI findings before and after the injections, we saw improvements in the tissue six months later in five of seven patients undergoing PRP and an appropriate rehabilitation program. The healing in the tissue appeared to correspond with the reported improvement of the pain and also with the clinical assessment of function.”
HOW DOES PRP WORK?
Prior to the preparation of platelet rich plasma, blood is drawn from the patient for the separation of platelets during the centrifugation process. After this is completed, the increased concentration of platelet rich plasma is combined with the remaining blood. It is then carefully injected with a needle into the injured area.
The entire process including preparation and cleaning of the injection site and recovery usually takes approximately not more than one hour. For a short period after the procedure, pain at the PRP injection site may increase; however, it typically diminishes within a couple of days. It may take a few weeks for the full benefits of the treatment to take effect. The most commonly reported side effect of the procedure is tenderness at the site of the injection. Because a PRP injection is conducted with the patient’s own blood, the risk of contamination and infection is greatly reduced.
Patients are encouraged to minimize activity for at least 24 hours following the procedure. However, most patients are able to participate in their daily activities immediately after the procedure. Patients should continue to participate in any ongoing physical therapy programs, and if they felt some relief from the platelet rich plasma therapy, additional treatments may be warranted.
CONDITIONS RELATED TO PRP THERAPY
Platelet rich plasma injections have demonstrated successful results in treating pain associated with torn ligaments and tendons, skeletal fractures, strained muscles, sprained knees and other joints, and other chronic tendon injuries. According to research published by the American Academy of Orthopaedic Surgeons, tennis elbow is one of the most common injuries that is successfully treated with PRP injections. Platelet rich plasma therapy is also a practical option when a patient’s heel becomes inflamed due to Achilles tendinitis.
Other frequent injuries that are treated with platelet rich plasma include:
Researchers are also currently conducting studies regarding the effectiveness of platelet rich therapy in the treatment of chronic arthritis of the knee.
Platelet rich plasma therapy has also been used following certain types of surgery to help tissues heal. The injection of the enhanced platelets is thought to expedite recovery, assist with the healing process, and increase mobility of the affected area.
Patients with several types of sports injuries and those recovering from certain surgeries may be viable candidates for PRP therapy. This minimally invasive treatment offers promising pain relief, while reducing the likelihood of infection, and the potential need for surgery. As research continues for this relatively new procedure, the medical community as well as patients will benefit from the potential effectiveness of platelet rich plasma therapy.
APPLICATION IN ORTHOPAEDIC SPORT MEDICINE
Regenerative medicine is a new, evidence based, multidisciplinary approach that seeks to repair or replace damaged or diseased human cells or tissues to restore normal function, which holds the promise of revolutionizing patient care in the 21st century. It uses autologous blood or bone marrow components to stimulate body’s own repair processes.
A common source for regenerative cells and growth factors is bone marrow aspirate concentrate (BMAC) and platelet rich plasma (obtained from one’s own blood). Both bone marrow concentrate and platelet rich plasma is used to augment and accelerate the body’s own healing mechanisms. These cells are naturally found in the body and are used to improve the healing of broken bones and injured muscles, tendon, ligament, as well as cartilage. When regenerative cells are used in high and optimal concentrations, they help speed up the healing process and can potentially facilitate repair of tissues that are no longer able to do so naturally.