What is Platelet Rich Plasma?
Platelet rich plasma (PRP) is comprised of concentrated platelet cells from blood. Platelet cells contain and secrete various cytoplasmic granules, lysosomal content, microparticles, and secrotomes. The three types of platelet secretomes include: alpha granules, dense granules, and lysosomal granules. These secretomes contain cytokines, chemokine, signaling molecules, and growth factors. Dense granules contain bioactive agents such as serotonin, histamine, dopamine, calcium, and adenosine. The alpha granules are primarily responsible for secreting the growth factors found in PRP:
| Growth factors | Origins | Physiological effects |
|---|---|---|
| PDGF | Neuronal cells, astrocytes, oligodendrocytes, vascular cells | Induces stem cell proliferation, neuroprotection, promotes cell migration and proliferation |
| TGF-β | β cells, T cells, dendritic cells, macrophages | Promoting cell proliferation and differentiation, assist with tissue repair and fibrosis, inhibit the activation of immune cells |
| VEGF | Endothelial cells, smooth muscle cells, platelets, neutrophils, macrophages | Angiogenesis and vascular repair, tissue repair, neuroprotection |
| IGF-1 | Hepatic stellate cells, osteoblasts, fibroblasts, macrophages | Promotes growth, cell differentiation, cell proliferation |
| bFGF | Endothelial cells, bone cells | Induction of neovascularization and neurotrophy |
| EGF | Vascular smooth muscle cells, endothelial cells, neutrophils, macrophages | Promotes wound healing, anti-inflammatory effects |
HOW DOES PRP WORK?
Platelet rich plasma (PRP) has a high concentration of growth factors that has shown in research studies to promote a signaling mechanism that attracts necessary healing factors and cells to the injured area. These growth factors are also involved in promoting new blood vessel formation to the injured site along with promoting new tissue growth and improving the quality of the tissue formed during the healing process. PRP also has demonstrated its ability to be involved with the regulation and reduction of inflammation and thus, has been associated with pain modulation.
Who is a Candidate for PRP Injections?
Ideal candidates for platelet rich plasma injections are individuals seeking a non-surgical solution for pain relief and tissue healing. These include people with chronic joint pain, arthritis, chondromalacia (cartilage damage), meniscus tears, labral tears, ligament sprains and tears, and tendinosis and tendon partial tears. PRP may be helpful in situations where traditional treatments such as rest, medications, chiropractic care, acupuncture, and physical therapy have not helped. Candidates may be seeking an alternative to surgery. A formal consultation with Dr. Yoon will be needed to determine if this treatment is appropriate.
WHAT CAN I EXPECT WITH PRP TREATMENT?
The consultation with Dr. Yoon will consist of a thorough evaluation and discussion. Dr. Yoon’s office will also provide a pre and post treatment guideline handout if treatment is pursued. Most treatments require abstaining from the use of non-steroidal anti-inflammatory medications (NSAIDs) one week before and two weeks after the procedure to allow the treatments to naturally work. Because many treatment protocols are tailored to the specific needs of the patient, expectations post treatment will be carefully explained beforehand. Necessary prescriptions for orthotics and other braces, biomechanics evaluations, physical therapy prescriptions, specific location and provider referrals, and other needs will be provided. Continuous patient follow-up will occur at specific timepoints to optimize treatment results.
WHY CHOOSE DR. STEVE YOON FOR PRP?
Dr. Steve Yoon is a highly regarded biologics expert utilizing platelet rich plasma (PRP) treatments in professional sports making him a top choice for PRP therapy for patients in Los Angeles and around the country. He has extensive experience utilizing platelet rich plasma while in his role as Director of Clinical Regenerative Medicine at the Cedars Sinai Kerlan Jobe Institute and as a treating consultant for the vast majority of professional sports teams and sports agencies throughout the country. Dr. Yoon has successfully treated patients over two decades while specializing in the use of platelet rich plasma and other regenerative therapies to enhance recovery and performance. His personalized and tailored approach with patients and helping them with their quality of life has earned him numerous honors including being recognized annually in Los Angeles as a Super Doctor as well as a Top Doctor nationally by Castle Connolly.
RESEARCH ARTICLES
Wang Z, Li Q, Zhang Y, Chen H, Liu S, Yang L. Efficacy and safety of platelet-rich plasma injections for the treatment of knee osteoarthritis: A systematic review and meta-analysis
Arthur Vithran DT, Xie W, Opoku M, Essien AE, He M, Li Y. The Efficacy of Platelet-Rich Plasma Injection Therapy in the Treatment of Patients With Achilles Tendinopathy: A Systematic Review and Meta-Analysis. J Clin Med. 2023;12(3):995. doi:10.3390/jcm12030995
Chen X, Zhang J, Huang J, Liu K, Zhao Y. Comparative efficacy of different doses of platelet-rich plasma in knee osteoarthritis: a meta-analysis. J Orthop Surg Res. 2025;20(1):650. doi:10.1186/s13018-025-05650-1
Mende E, Sun M, Zhang A. A comprehensive summary of the meta-analyses and systematic reviews on platelet-rich plasma in osteoarthritis and musculoskeletal conditions. Mil Med. 2024;189(11-12):e2347-e2359. doi:10.1093/milmed/usae167
Kwong CA, Woodmass JM, Gusnowski EM, Bois AJ, Leblanc J, More KD, Lo IKY. Platelet-Rich Plasma in Patients With Partial-Thickness Rotator Cuff Tears or Tendinopathy Leads to Significantly Improved Short-Term Pain Relief and Function Compared With Corticosteroid Injection: A Double-Blind Randomized Controlled Trial. Arthroscopy. 2021;37(2):510-517. doi:10.1016/j.arthro.2020.10.037
Zeng C, Pan X, Li H, Li Y. Efficacy and safety of platelet-rich plasma injections for the treatment of osteoarthritis: a meta-analysis. Front Med. 2023;10:1204144. doi:10.3389/fmed.2023.1204144