# PRP and biologic treatments: growth factors for joints and tendons PRP is plasma from your own blood, rich in platelets and growth factors. It is injected into the joint or tendon that hurts. Here is where it truly helps, where it does not, and what to expect. ## What PRP is PRP stands for platelet-rich plasma. Platelets are known for clotting blood. They also carry growth factors, proteins that regulate inflammation and tissue healing. With a simple blood draw and a spin in a centrifuge, the platelets are concentrated in a small volume of plasma. That concentrate is injected where it is needed. Because it comes from your own blood, there is no risk of allergy or rejection. ## What “biologic treatments” means The term covers treatments that use the body’s own material, or substances naturally found in the joint, to improve the joint environment and not only mask the pain. - **PRP (growth factors).** The most studied biologic treatment in orthopaedics. - **Hyaluronic acid.** An injectable joint lubricant. It can be given alone or together with PRP. - **Cell-based treatments.** Bone marrow aspirate concentrate (BMAC) or preparations from fat tissue. Studies are still limited and their use is discussed only in selected cases. Which treatment suits you, and whether any does, becomes clear at the examination. ## Which conditions it helps Results are best when the damage is not advanced. - **Early to moderate knee osteoarthritis.** This is where most of the studies are. - **Long-standing tendon problems.** Tennis elbow, patellar tendon pain, Achilles tendon pain, plantar fasciitis. - **Early hip osteoarthritis** and other joints, in selected patients. - **Muscle and ligament injuries** in active people, as part of a rehabilitation programme. ## Who is a good candidate We see the best results in people with early or moderate wear, who still have cartilage to protect, and in those with long-standing tendon pain that did not settle with physiotherapy. It helps as well to have realistic expectations and to be willing to follow the exercise programme alongside. You are less likely to benefit if the X-ray shows that the joint space has closed, if the leg has drifted far out of line, or if the problem is mechanical. ## When it is not the right choice When the cartilage is fully worn and bone rubs on bone, an injection does not change the picture. There the conversation is about a [knee replacement](https://www.manoskotidis.com/en/robotic-knee-replacement-cori/) or a [hip replacement](https://www.manoskotidis.com/en/hip-replacement-asi/). The same goes for a knee that locks because of a [meniscus tear](https://www.manoskotidis.com/en/knee-arthroscopy-meniscus/): a mechanical problem needs a mechanical fix. PRP is also avoided during an active infection, in some blood disorders, with a low platelet count and with active cancer. If you take blood thinners or anti-inflammatory medication, tell the doctor before the injection. ## PRP or cortisone? A cortisone injection acts fast and is useful in a sharp flare of inflammation. Its effect usually lasts a few weeks, though, and frequent repeats are not good for cartilage and tendons. PRP acts more slowly. In comparative studies its benefit appears to last longer. They are not rival treatments. Each has its place, and the choice depends on what you need right now. ## Getting ready for the injection - Tell the doctor about all the medication you take, especially blood thinners and anti-inflammatory drugs. - You are usually asked to avoid anti-inflammatory drugs for a few days before and after, because they affect how platelets work. - Drink plenty of water the day before and on the day. It makes the blood draw easier. - If you have a fever or an infection, the injection is postponed. - Plan a quiet schedule for the next two to three days. ## How it is done, step by step - **Blood draw.** A small amount of blood from a vein in the arm, as in a routine test. - **Centrifuge.** The blood separates within minutes and the plasma with the platelets is collected. - **Injection.** The PRP is injected into the joint or around the tendon, under sterile conditions. - **Home.** The whole visit usually takes less than an hour and you walk out afterwards. A course of one to three injections, a few weeks apart, is often suggested. The number depends on the condition and on how you respond. ## What to expect afterwards For the first one to three days you may feel more pain or swelling at the site. This is expected and it settles. A few days away from hard activity, ice and no anti-inflammatory medication are usually advised, following your doctor’s instructions. Improvement is not instant. It comes gradually over the following weeks. In knee osteoarthritis, when there is a response, the benefit usually lasts several months and the treatment can be repeated. ## The injection does not work alone PRP calms inflammation and opens a window with less pain. What you do inside that window decides the result. Strengthening the muscles around the joint, correcting the way you load the leg and keeping your weight in check are what make the benefit last. For tendon problems, PRP is always paired with a programme that loads the tendon progressively. Without it, the pain usually comes back. ## What the studies show In early and moderate knee osteoarthritis, several comparative studies show that PRP reduces pain and improves function for 6 to 12 months, often more than hyaluronic acid. Not all studies agree, though, and international guidelines are not unanimous. One reason is that “PRP” does not always mean the same preparation. Platelet concentration and the way it is prepared differ from system to system. For tendons, the most consistent data concern tennis elbow. In plain words: it is a safe option that helps a good number of patients, not all of them. There is no proof that it rebuilds cartilage. ## Myths and facts - **Myth:** “PRP regrows cartilage.” **Fact:** It reduces inflammation and pain. Cartilage regrowth has not been proven. - **Myth:** “With PRP I will surely avoid surgery.” **Fact:** It can buy time and quality of life. In advanced wear it does not replace a joint replacement. - **Myth:** “It is stem cells.” **Fact:** PRP contains platelets and growth factors, not stem cells. - **Myth:** “All PRP is the same.” **Fact:** The preparation and the injection technique matter. ## What to ask before you decide - What stage is my joint wear and what can I realistically expect? - How many injections do you suggest, and how far apart? - What else should I do alongside? Exercise, physiotherapy and weight control count as much as the injection. - What is the total cost? Biologic treatments are usually not covered by insurance. ## Common questions ### Does a PRP injection hurt? You feel a prick, as with any injection. For one to three days afterwards there may be soreness or swelling, which settles. ### How many injections will I need? Usually one to three, a few weeks apart. It depends on the condition and on how you respond. ### When will I see a result and how long does it last? Improvement comes gradually, within a few weeks. In knee osteoarthritis the benefit usually lasts several months and differs from person to person. ### Is it safe? Because your own blood is used, serious side effects are rare. As with any injection there is a small risk of infection, which is why it is done under sterile conditions. ### PRP or hyaluronic acid? It depends on the joint, the stage of wear and your age. In several knee studies PRP had a longer effect. In some cases the two are combined. ### Can I work on the same day? For desk work usually yes. For manual work or training it is better to wait a few days. ### When can I return to sport? Gentle activity starts after a few days. Hard training returns gradually, following the programme you will be given. --- Manos Skotidis, MD, MSc · Orthopaedic Surgeon · Hip & Knee Phone: +30 694 248 7303 · Email: em.skotidis@gmail.com Appointments: https://www.manoskotidis.com/en/#book