PRP treatments involve collecting a small amount of your blood and spinning it in a centrifuge to separate the platelets from the red cells. The collected platelets are then injected back into the injured area to stimulate healing and regeneration. PRP puts specific components in the blood to work. Blood is made up of four main components; plasma, red blood cells, white blood cells, and platelets. Each part plays a role in keeping your body functioning properly. Platelets act as wound and injury healers. They are first on the scene at an injury, clotting to stop any bleeding and immediately helping to regenerate new tissue in the wounded area.

The platelets contain healing agents, or “growth factors.” Let’s look at some of the growth factors and what they do:

  • Platelet-derived growth factor (PDGF) is a protein that helps control cell growth and division, especially blood vessels. When more blood (and the oxygen it carries) is delivered to the site of a wound, there is more healing.
  • Transforming growth factor beta (or TGF-β) is a polypeptide and is important in tissue regeneration.
  • Insulin-like growth factors are signaling agents. They help change the environment of the damaged joint from diseased to healing by “signaling” the immune system to start rebuilding tissue.
  • Vascular endothelial growth factor (VEGF) is an important protein that brings healing oxygen to damaged tissue where blood circulation might be damaged or inadequate.
  • Epidermal growth factor plays a key role in tissue repair mechanisms.


Researchers at the University of Memphis and Saint Louis University acknowledge that there is little doubt that the growth factor milieu contained within PRP has the potential to be highly beneficial to bone regeneration.(1In fact, PRP is such a promising treatment for bone regeneration that doctors also support the use of PRP for large bone defects to assist healing and bone regeneration.2 Researchers have confirmed that PRP accelerates the healing and growth of bone in large-bone tumor-created defects and other defects.3,4 It is also being studied for routine use in regeneration of cystic bony defects (characteristics of bone tumors) in children.5

Hip Osteoarthritis

  • Researchers at the University of Florence found that the majority of patients receiving PRP for hip osteoarthritis had significant pain reduction at 6-7 weeks that was sustained at 6 months, and they also had better range of motion.6
  • More Italian research from the Rizzoli Orthopedic Institute showed improved findings: “Results indicated that intra-articular PRP injections offer a significant clinical improvement in patients with hip osteoarthritis without relevant side effects.”7
  • Even after hip surgery, researchers in Chile noted that PRP was effective in reducing pain that continued after the surgery.8

Hip OA is treated almost daily in my office. The most amazing recovery is that of a man who was a life-long body builder. His left hip was almost fused, with no range of motion. I refused to treat the hip since I didn’t think PRP would help. Instead I used PRP on his right knee. After some success with his knee he begged me to inject his hip. I finally did, and to my surprise, he was then able to reach down to the floor to pick up weights. A movement he could not do for years before.

Degenerative Disc Disease

Research has shown PRP to be effective in treating degenerative disc disease (DDD) by addressing the problems of spinal ligament instability and by stimulating the regeneration of the discs indirectly (although discs were not directly injected, they showed an increase in disc height).9

Although I don’t typically consider DDD to be a major player in neck or back pain, I do treat these areas daily. From my exam, it is typically not the discs that are the issue, but the ligaments at their connection to bone that cause the pain. This is called an enthesopathy. And typically, it is easy to heal with PRP. Please be very careful to not have surgery for areas that can heal with PRP. As you will read, areas in MRIs that show anatomical issues, may not be the pain generator.

Knee Osteoarthritis

One study showed that “[I]ntra-knee articular injection of PRP to treat knee articular cartilage degeneration is safe, [and] can alleviate symptoms of pain and swelling and improve the quality of life of patients.”10 Researchers in Barcelona, Spain were able to report results at six months showed improvements in patients’ knee function and quality of life.11

Another study from doctors in Thailand found that PRP produced greater improvement in knees than hyaluronic acid injection and placebos in terms of reducing symptoms and improving function, as well as in improving quality of life.12 In a study from the Mayo Clinic, PRP was seen to be more effective than hyaluronic acid in younger, active patients with low-grade osteoarthritis.13

PRP has demonstrated significant improvements in Knee Injury and Osteoarthritis Outcome Scores, including pain and symptom relief, in addition to having the ability to provide pain relief, halt progression of meniscal damage, and regenerate tissue.14,15

In supportive research in the surgical journal Arthroscopy, doctors concluded that PRP injections are a viable treatment for knee osteoarthritis and should be considered for patients with this condition.16
Studies like these add to the accumulating evidence that PRP can halt and reverse meniscus degeneration.17,18,19

The most common issue that I see in the office is knee OA. I inject PRP and stem cells into many knees every day. I use an ultrasound to guide the needle to make sure the solution enters the joint. Without ultrasound guidance, there is a 33% chance that the solution will actually miss the joint, and end up in the soft tissue. Not only will that not be a healing action, but it can cause a huge inflammatory reaction with an effusion (fluid in the knee). I have heard patients say that having a baby was easier.

Kneecap and Tendons

Patellar tendinopathy, often called “runner’s knee,” is a condition that has been shown to respond very favorably to Platelet-Rich Plasma Therapy. Researchers in the Netherlands reported: “After PRP treatment, patients with patellar tendinopathy showed a statistically significant and meaningful improvement.”20

Rotator Cuff- Shoulder

  • Injections of PRP have led to reduced pain and improved recovery for the treatment of rotator cuff tears.21,22
  • PRP also enhances rotator cuff repair following arthroscopic shoulder surgery.23
  • At a meeting of the American Academy of Orthopaedic Surgeons, researchers suggested that PRP injections may be a safe and cost-effective treatment alternative for rotator cuff tendinopathy (RCT) .My experience is that it also works on full-thickness tears. I inject shoulders every day, and have seen patients who can’t lift their arm because of a tear, get pain free, complete range of motion.24

Tennis Elbow

Patients with chronic lateral epicondylitis, known as tennis elbow, received PRP injections once or twice at four-week intervals in a recent study, complemented with standardized physical therapy. Six months after the localized PRP treatment, these patients reported significant pain relief and gain in function, as well as improved quality of life. According to doctors at the Rizzoli Orthopedic Institute and University of Bologna in Italy, a single PRP injection may be sufficient.25 Doctors from the United Kingdom confirmed these findings, showing that PRP injections have an important and effective role in treatment of the elbow, especially in difficult cases of tennis elbow.26

Achilles Tendinopathies- Ankle/Foot

For patients with Achilles tendinopathy and plantar fasciitis, PRP was found to be an effective and safe alternative for those with a poor response to conventional nonsurgical treatments in two studies.27,28
In a of study patients affected by mid-portion Chronic Recalcitrant Achilles Tendinopathies, PRP was found to be effective even in a single treatment.29 Again, these are areas common to my injections. Ultrasound is a necessity to guide a needle to the plantar fascia attachment on the calcaneus (heel bone). The common approach is through the bottom of the foot which is very painful, but with an ultrasound, the needle can be guided through the less sensitive medial surface of the foot.


  • Doctors in Egypt studied 50 patients with TMJ-osteoarthritis. They found that PRP performed better than hyaluronic acid during long-term follow-up in terms of pain reduction and increased interincisal distance – that is, the ability to open one’s mouth wider.60 In a study done in Turkey, researchers concluded that patients suffering from temporomandibular joint (TMJ) disc dislocation benefited more from PRP injections than from surgery to manipulate the jaw back into place. Clearly, PRP stabilized the joint and reduced chronic instability.30
  • A study in Poland found that platelet-rich plasma injections into the temporomandibular joint had a positive impact on the reduction of the intensity of pain experienced by patients who were being treated for TMJ dysfunction.31

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1. Rodriguez IA, Growney Kalaf EA, Bowlin GL, Sell SA. Platelet-rich plasma in bone regeneration: engineering the delivery for improved clinical efficacy.BioMed Res Int. 2014;2014:392398. doi:10.1155/2014/392398
2. Oryan A, Alidadi S, Moshiri A Platelet-rich plasma for bone healing and regeneration. Expert Opin Biol Ther. 2015 Dec 4:1-20. [Epub ahead of print.]
3. Mattiello A, Cacciapuoti C. Autologous platelet gel improves bone reconstruction of large defects in patients with bone giant cell tumors. In Vi vo. 2015 Sep-Oct;29(5):533-540.
4. Civinini R, Macera A, Nistri L, Redl B, Innocenti M. The use of autologous blood-derived growth factors in bone regeneration. Clin Cases Miner Bone Metab. 2011 Jan-Apr; 8(1):25-31.
5. Nagaveni NB, Praveen RB, Umashankar KV, Pranav B, Sreedevi R, Radhika NB. Efficacy of platelet-rich plasma (PRP) in bone regeneration after cyst enucleation in pediatric patients–a clinical study. J Clin Pediatr Dent. 2010 Fall;35(1):81-7.
6. Civinini R, Nistri L, Martini C, Redl B, Ristori G, Innocenti M. Growth factors in the treatment of early osteoarthritis. Clin Cases Miner Bone Metab. 2013 Jan;10(1):26-9. doi: 0.11138/ccmbm/2013.10.1.026. PubMed Abstract.
7. Dallari D, Stagni C, Rani N, Sabbioni G, Pelotti P, Torricelli P, Tschon M, Giavaresi G. Ultrasound-guided injection of platelet-rich plasma and hyaluronic acid, separately and in combination, for hip osteoarthritis: a randomized controlled study. Am J Sports Med. 2016 Jan 21. pii: 0363546515620383. [Epub ahead of print]
8. Rafols C, Monckeberg JE, Numair J, Botello J, Rosales J. Platelet-rich plasma augmentation of arthroscopic hip surgery for femoroacetabular impingement: a prospective study with 24-month follow-up. Arthroscopy. 2015 Oct;31(10):1886-92. doi: 10.1016/j.arthro.2015.03.025. Epub 2015 May
8. Gullung GB, Woodall JW, Tucci MA, James J, Black DA, McGuire RA. Platelet-rich plasma effects on degenerative disc disease: analysis of histology and imaging in an animal model. Evid Based Spine Care J. 2011 Nov;2(4):13-8. doi: 10.1055/s-0031-1274752.
9. Khalaf K, Nikkhoo M, Ya-Wen Kuo, Yu-Chun Hsu, Parnianpour M, Campbell-Kyureghyan N, Haghpanahi M, Jaw-Lin Wang. Recovering the mechanical properties of denatured intervertebral discs through Platelet-Rich Plasma therapy. Conf Proc IEEE Eng Med Biol Soc. 2015 Aug; 933-6. doi: 10.1109/EMBC.2015.7318516.
10. Li M, Zhang C, Ai Z, Yuan T, Feng Y, Jia W. Therapeutic effectiveness of intra-knee-articular injection of platelet-rich plasma on knee articular cartilage degeneration. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2011 Oct;25(10):1192-6.
11. Wang-Saegusa A, Cugat R, Ares O, et al. Infiltration of plasma rich in growth factors for osteoarthritis of the knee short-term effects on function and quality of life. Arch Orthop Trauma Surg. 2011 Mar;131(3):311-7. Epub 2010 Aug 17.
12. Kanchanatawan W et al. Short-term outcomes of platelet-rich plasma injection for treatment of osteoarthritis of the knee. Knee Surg Sports Traumatol. Arthrosc. 2015 Sep 19. [Epub ahead of print]
13. Pourcho AM, Smith J, Wisniewski SJ, Sellon JL. Intraarticular platelet-rich plasma injection in the treatment of knee osteoarthritis: review and recommendations. Am J Phys Med Rehabil. 2014 Nov;93(11 Suppl 3):S108-21. doi: 10.1097/PHM.0000000000000115.
14. Sampson S, Reed M, Silvers H, et al. Injection of platelet-rich plasma in patients with primary and secondary knee osteoarthritis: a pilot study. Am J Phys Med Rehabil. 2010 Dec;89(12):961-9.
15. Blanke F, Vavken P, Haenle M, von Wehren L, Pagenstert G, Majewski M. Percutaneous injections of platelet-rich plasma for treatment of intrasubstance meniscal lesions. Muscles Ligaments Tendons J. 2015 Oct 20;5(3):162-166.
16. Campbell KA, Saltzman BM, Mascarenhas R, Khair MM, Verma NN, Bach BR Jr, Cole BJ. A Systematic Review of Overlapping Meta-analyses. Arthroscopy. 2015 Nov;31(11):2213-21. doi: 10.1016/j.arthro.2015.03.041. Epub 2015 May 29.
17. Wu CC, Chen WH, Zao B, Lai PL, Lin TC, Lo HY, Shieh YH, Wu CH, Deng WP. Regenerative potentials of platelet-rich plasma enhanced by collagen in retrieving pro-inflammatory cytokine-inhibited chondrogenesis. Biomaterials. 2011 Sep;32(25):5847-54. Epub 2011 May 25.
18. van Buul GM et al. Platelet-rich plasma releasate inhibits inflammatory processes in osteoarthritic chondrocytes. Am J Sports Med. 2011 Nov;39(11):2362-70. Epub 2011 Aug 19.
19. Kon E, Buda R, Filardo G, Di Martino A, Timoncini A, Canacchi A, Fornasari PM, Giannini S, Marcacci M. Platelet-rich plasma: intra-articular knee injections produced favorable results on degenerative cartilage lesions. Knee Surg Sports Traumatol Arthrosc. 2010; 18(4):472-479.
20. Gosens T, Den Oudsten BL, Fievez E, van ‘t Spijker P, Fievez A. Pain and activity levels before and after platelet-rich plasma injection treatment of patellar tendinopathy: a prospective cohort study and the influence of previous treatments. Int Orthop. 2012 Apr 27.
21. Mei-Dan O, Carmont MR. The role of platelet-rich plasma in rotator cuff repair. Sports Med Arthrosc. 2011 Sep;19(3):244-50. doi: 10.1097/JSA.0b013e318227b2dc.
22. von Wehren L, Blanke F, Todorov A, Heisterbach P, Sailer J, Majewski M. The effect of subacromial injections of autologous conditioned plasma versus cortisone for the treatment of symptomatic partial rotator cuff tears. Knee Surg Sports Traumatol.Arthrosc. 2015 May 28. [Epub ahead of print]
23. Yang J, Sun Y, Xu P, Cheng B. Can patients get better clinical outcomes by using PRP in rotator cuff repair: a meta-analysis of randomized controlled trials. J Sports Med Phys Fitness. 2015 Oct 16.
25. Salamanna F, Veronesi F. New and emerging strategies in platelet-rich plasma application in musculoskeletal regenerative procedures: general overview on still open questions and outlook. BioMed Research International. Volume 2015 (2015), Article ID 846045, 24 pages
26. Murray DJ, Javed S, Jain N, Kemp S, Watts AC. Platelet-rich plasma injections in treating lateral epicondylosis: a review of the recent evidence. J Hand Microsurg. 2015 Dec;7(2):320-325. Epub 2015 Jul 8.
27. Guelfi M, Pantalone A, Vanni D, Abate M, et al. Long-term beneficial effects of platelet-rich plasma for non-insertional Achilles tendinopathy. Foot Ankle Surg. 2015 Sep;21(3):178-81. doi: 10.1016/j.fas.2014.11.005. Epub 2014 Dec 11. PubMed Abstract.
28. López-Gavito E, Gómez-Carlín LA, Parra-Téllez P, Vázquez-Escamilla J. Platelet-rich plasma for managing calcaneus tendon tendinopathy and plantar fasciitis. Acta Ortop Mex. 2011 Nov-Dec;25(6):380-5. PubMed PRP Abstract.
29. Gaweda K, Tarczynska M, Krzyzanowski W. Treatment of Achilles tendinopathy with platelet-rich plasma. Int J Sports Med. 2010 Aug;31(8):577-83. Epub 2010 Jun 9. PubMed Abstract.
30. Hegab AF et al. Platelet-Rich Plasma Injection as an Effective Treatment for Temporomandibular Joint Osteoarthritis. J Oral Maxillofac Surg. 2015 Sep;73(9):1706-13. doi: 10.1016/j.joms.2015.03.045. Epub 2015 Mar 24.
31. Hancı M, Karamese M, Tosun Z, Aktan TM, Duman S, Savaci N. Intra-articular platelet-rich plasma injection for the treatment of temporomandibular disorders and a comparison with arthrocentesis. J Craniomaxillofac Surg. 2015 Jan;43(1):162-6. doi: 10.1016/j.jcms.2014.11.002. Epub 2014 Nov 15.

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