Platelet-rich plasma (PRP) (also known as blood injection therapy)) is a medical treatment being used for a wide range of musculoskeletal problems. Platelet-rich plasma refers to a sample of serum (blood) plasma that has as much as four times more than the normal amount of platelets.
Platelets are like the emergency medical technicians (EMTs) of the body. When there’s an injury, they are the first one on the scene of the accident, so-to-speak. Platelets have a large number of available growth factors and other bioactive molecules that signal the body to start the tissue-healing process. This treatment enhances the body’s natural ability to heal itself and is used to improve healing and shorten recovery time from acute and chronic soft tissue injuries.
It has been used for years after plastic surgery and surgery on the mouth, jaw, and neck. It seems to promote bone graft healing. Researchers have found a way to combine this substance with other chemicals to make it into a putty or gel that can be painted on a surgical site to speed up healing.
Blood injection therapy of this type has been used for knee osteoarthritis, degenerative cartilage, spinal fusion, bone fractures that don’t heal, and poor wound healing. This treatment technique is fairly new in the sports medicine treatment of musculoskeletal problems, but gaining popularity quickly.
Patients with chronic tendinitis (e.g., tennis elbow, patellar tendinitis or jumper’s knee, Achilles tendinitis) have also benefited from this treatment. It’s even being tried on hernias, labral (shoulder cartilage) tears, meniscal tears of the knee, and ankle sprains. Some surgeons are using it more and more with any orthopedic surgery involving the soft tissues to augment (reinforce) bone or ligamentous graft materials already being used.
New treatments are always welcomed, especially if they speed up the healing process. But the question is: how well are platelet-rich plasma treatments really working for muscle, tendon, ligament, and labral repairs? The authors of this report performed a search of all related studies published over the last 10 years on this topic.
They found that the basic science behind this technique is sound. Animal studies have shown very favorable results. But the number and type of studies using platelet-rich plasma in humans is very limited. And the way the different studies were conducted makes it difficult to compare or combine the results.
There are also different growth factors released and different concentrations of platelets in samples used from study to study. It’s not really clear yet just how much platelet-rich plasma is needed for each type of injury or even how many platelets are needed for the best response.
The idea that platelet-rich plasma treatment could heal a tendon tear is appealing. Most tendon tears just fill in with scar tissue. The result is often more tears later or even chronic pain. A complete and natural healing of tendon tissue would benefit many people, especially athletes involved in repetitive activities that stress tendons where they attach to the bone.
Of the studies that have been done in humans, there have been good results. For example, athletes who had surgery to repair ruptured tendons or rotator cuff tears and then received platelet-rich plasma regained joint motion faster. They had fewer complications from the surgery. And they were able to get back to training sooner than patients who did not receive the platelets.
One study on the use of platelets to heal cartilage lesions showed improved function and less pain compared with the group who did not receive this treatment. Currently, there are no reported studies using platelets with muscle injuries in humans. This is an area for future research.
The authors conclude that platelet-rich plasma at the site of soft tissue injury has the ability to create an ideal healing environment. This has been shown in animal studies and now in a limited way in humans. The treatment is simple, easy to do, and inexpensive.
There are very few side effects and most of these are very minor. For example, there is always the risk of infection. A small number of patients have reported increased pain, redness, and swelling at the injection site but this response didn’t last long.
The lack of high-quality, randomized controlled trials points to the need for attention in this area. Before expanding its use to an even wider array of musculoskeletal problems, it should be proven that the treatment has a positive benefit for each type of injury or trauma.