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. 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.
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.
As with any new treatment, over time it is possible to see more clearly the pros and cons of treatment. Data can be collected on long-term results and more information published to guide surgeons in using this treatment tool. In this article, research on the subject of platelet-rich plasma to augment connective tissue healing is offered by the Orthopaedic Research Society (ORS).
Taking a look back over the past few years, we now see there are some inconsistencies in results with this treatment. Some studies have shown no benefit from the use of platelet-rich plasma (PRP) for tissue healing. Why is that? The authors propose several reasons for the variable results reported in the literature.
First, not all PRP is the same. The product may vary based on how much whole blood was taken and how quickly platelets recover during the injection. The presence of other blood parts such as red or white blood cells can make a difference. And any other substances that might have been added (e.g., thrombin, calcium chloride) can affect how the PRP functions.
Second, the potency (strength) of each PRP preparation varies — again, this depends on what’s in the product. Too little or too much of any component part can change how quickly and how effectively the body responds to the product. Then there is what’s called biologic variation — everyone responds a little differently to the same PRP. Individual body chemistry, metabolism, and reactivity can vary significantly.
Along these same lines, getting the right mix of product for each person is a challenge. Clearly, one formulation does not fit all. The amount of PRP to achieve the best result for each person is called the dose-response. This goes back to how the body responds to each substance within the PRP (e.g., growth factors, cytokines, proteins, clotting factors).
And finally, even with the right mix of elements within the PRP, using it at the exact right time for best results may make a difference. The best timing for the use of PRP has not yet been determined. Likewise, the way in which the PRP is delivered (e.g., injected, brushed on) might make a difference in results.
The authors conclude that any future research done using PRP will have to pay attention to which PRP product was used and how it was used. The early enthusiasm about PRP may be still warranted but since not all results have been positive, it’s time to take a closer look before continuing as if this product is fail-proof.