PRP. Platelet-rich plasma. It’s a relatively new treatment used for rehab of injured tissues, and is considered a “regenerative medicine” modality. Blood is taken from the athlete, placed in a centrifuge so that platelets, which are fragments of blood cells involved in the clotting process, are concentrated. The injection of these platelets into injured tissues stimulates the release of the body’s own growth factors, which in turn stimulate an increase in cells that repair injured tissues. In theory, the body should in time be able to do the job on its own. But where there is chronic tendinopathy, as is often the case with proximal hamstring tendons, it’s hard for the body to get ahead of it and an acute problem becomes chronic. PRP has been shown to be a viable option as reported in the Muscle, Ligaments, and Tendons Journal (is there not a research journal for everything!)
Hamstrings are often the runner’s nemesis. Yet we couldn’t run without them. Our hamstrings allow us to pull our leg backward (concentric movement) so we move forward and when the leg is extending in front of us, they serve as an eccentric brake to keep our gait controlled and rhythmic. They work in concert with the quadriceps. One extends while the other contracts and visa versa. The quads are inherently larger and stronger than the hamstrings, but if the resulting imbalance is too great it can lead to a pulled, or strained, hamstring. When the extent of this imbalance persists, it puts added stress on the tendon that attaches below the hip on a projection called the ischial tuberosity (our butt bone!). Over time the tendon weakens and stretches until it tears. And with limited blood supply, tendons don’t self-repair quickly.
I’ve now had this issue for the past six months. PT and dry needling helped some but the condition would not go away, so my PT referred me to a sports medicine practice, which then ordered an MRI that showed a partial tear of my proximal hamstring tendon. I’ve been quite limited in how much and how hard I can run and race. Recent efforts were essentially a fast jog. So, I am scheduled in a week for a PRP injection.
PRP is not a silver bullet. Rather it is a process. One cannot expect to run or do anything strenuous in the lower extremity for at least six weeks. And then incrementally return to action — a bitter pill for a runner! The good news is about 50% of patients eventually find complete relief and are back to pre-injury activity within three months; another 40% have partial relief that may improve further over time; and only 10% see no improvement. I see those as decent odds!
I’ll blog on my experience with PRP, which might help some of you decide whether this is an option for you. Here’s hoping!