Platelet rich plasma, or PRP, is the product of an autologous (your own) blood preparation. When whole blood is spun at high rates (centrifuged) it becomes layered in its different constituencies. The lower proportion of the plasma layer is very high in platelets and growth factors. This layer of the separated blood is called PRP. In a standard PRP preparation, four blood withdrawal tubes are used to attain the optimal amount of PRP.
The problem when one injures the meniscus, is that it does not heal itself as it has no blood supply. For this reason, most meniscal surgeries involve removing the torn piece. The meniscus is however there for a reason and an attempt should be made, where possible, to save the meniscus and repair it.
Although the exact mechanism by which PRP alleviates symptoms and pain remain unknown, PRP contains a high concentration of platelets, as well as various other growth (healing) factors, including platelet-derived epithelial growth factor (PD-EGF), platelet-derived growth factor (PDGF) A and B, transforming growth factor (TGF) 1, Insulin-like growth factor (IGF) I and II, vascular endothelial growth factor (VEGF), endothelial cell growth factor (ECGF) and basic fibroblast growth factor (bFGF). It is thought that these growth factors, among others, may stimulate the healing response.
A PRP injection may help alleviate your pain and symptoms. The most common indications for the use of PRP in our clinic are for chronically painful tendons (mostly Patellar tendinopathy or Jumpers knee) and cartilage lesions. In patients with symptomatic and painful conditions, such as cartilage lesions, PRP may be used as a conservative treatment and an effective alternative to surgery.
For the preparation of the PRP, a doctor or a qualified nurse or phlebotomist will draw 20ml of whole blood of your own blood. The blood is then taken to our laboratory and the PRP is prepared from the whole blood on the premises. The whole preparation procedure will take approximately 20 minutes. The PRP preparation is then bought back to the clinic and is ready to be injected into the specific site. The doctor will then inject it into the area that is causing the problem. This is usually repeated 3 times 1-2 weeks apart but does vary between patients.
PRP is generally stimulating the healing process and thereby causing inflammation. Patients may therefore feel, for the initial 1-2 days, that there is increased pain in the area where the injection was given. This does settle down after a few days but can initially be quite painful. This is nothing to be concerned about and is generally what we see happening.
You may continue to exercise as per normal but may need to ease off the intensity level for a few days, until the initial pain has subsided. It is actually important to continue to exercise and rehabilitate the knee after the PRP injection. This however does not mean to overdo it but rather to exercise in the correct manner and to do the right exercise.
The PRP injection is part of the healing process and will definitely aid in this process. It is however not a "miracle" cure and needs to be used in conjunction with rehabilitation.