Natural healing relies on blood flow to an injured area. If we cut ourselves, the area gets red, hot and swollen because of the acute inflammation with a primary goal of healing that tissue.
FIRST - Platelets in our blood moving past the injury are activated to form a clot and prevent us from bleeding to death.
SECOND - Platelets organize a healing response by communicating with the local environment, switching on biological healing pathways.
Even in patients who have severely low platelet counts, these mechanisms are active enough to prevent our bodies from falling apart and continue our daily activities. Our bodies are constantly degenerating and regenerating tissue. The branch of medicine that has so many people so excited, regenerative medicine, is special because it is the first real push to help and improve our bodies natural regenerative healing processes, instead of trying to cover up pain when degenerative disease starts to take a toll on us. For now, we are studying using platelet and stem cell injections in response to injury, pain and dysfunction - but what if this turns out to be a preventative field of medicine as well?? That is what excites me the most. How could it be preventative? Let's take a look.
Osteoarthritis is defined as degeneration of joint cartilage and the underlying bone. In knees, and in general, cartilage is not a well vascularized tissue. This means when it is injured, it does not receive a lot of blood flow. Without blood flowing to the injured cartilage, the platelets cannot organize the healing response to regenerate the tissue. (Compare this to bone and muscle, which are both very well vascularized, and heal very well when they are torn or fractured).
So without a lot of blood flow, where does our knee cartilage get the nutrients it needs to survive? What helps organize the normal protective mechanisms of regeneration in response to the degenerative stress we place on our joints with daily wear and tear from simple activities, exercise or sport?
Research shows that the synovial fluid in the knee joint plays an important role in protecting the cartilage. Synovial fluid is a thick gel-like liquid that cushions the knee, & helps absorb daily impact from walking, running and climbing stairs. The healthy synovial fluid normally found in joints is made by a lining of tissue around the knee, called the synovial lining, and it contains PROTEINS DERIVED FROM THE BLOOD PLASMA AND PROTEINS PRODUCED BY CELLS WITHIN THE JOINT TISSUES. The synovial lining even has stem cells responsible for joint health. The other areas of the knee joint that contains stem cells responsible for preserving the joint are the bones and the fat pad. All of these tissues communicate to organize regenerative processes that heal cartilage. The synovial fluid picks up signals from the cartilage, cellular mechanisms change in response to these signals, and our body does the best job it can to heal worn areas on a daily basis.
Studies have shown changes in the makeup of the synovial fluid in response to bursitis, synovitis, different types of arthritis and other injuries. This is an ongoing process adapting to preserve our joints. When the negative degenerative processes are too strong, we lose cartilage quicker than we can regenerate it.
By measuring proteins and other contents of joint fluid before and after injections with platelet rich plasma (PRP) we have seen the positive effects these injections can have. Joints that were full of degenerative cellular mechanisms can be altered with an injection of PRP into the joint. By adding the plasma and proteins through injection, we can boost the healthy joint preservation biological processes. This includes influencing the activity of the local mesenchymal stem cells (MSCs).
For now, research is being done on PRP injections in response to pain and dysfunction, and the systematic reviews of the evidence show that PRP is better than placebo, saline, corticosteroids (cortisone) and hyaluronic acid (gel) injections.
So, if you had to choose a treatment for knee pain and dysfunction, an injection with platelet rich plasma has been shown to be a safe and effective method - outperforming all the traditional treatments. In some cases it can prevent surgery in patients who otherwise would have had no options left to treat their pain and dysfunction.
Maybe in the future, we will perform these injections every few months or yearly to help preserve our joints instead of waiting for pain and dysfunction.