• Arthritis
  • Tennis Arm (Tendinopathy)
Rhone-Poulenc Rorer Physical Medicine & Rehabilitation Scholarship
Pan-Pacific Surgical Association Award for Outstanding Achievement in the Field of Research
Medical Research Award for Outstanding Achievement In the Field of Research
Marc Darrow MD – PRP Therapy

Marc Darrow MD

    Stem Cell Institute Dr. M. Darrow

    Stem Cell Institute Dr. M. Darrow

11645 Wilshire Blvd., Suite 120, Los Angeles, CA 90025
(800) 734-2210    


Does Platelet Rich Plasma Therapy (PRP) work?

In recent research doctors looked at the increasing popularity of platelet-rich plasma therapies for soft tissue injuries such as ligament, muscle and tendon tears and tendinopathies.

They noted that PRP can be used as a principal treatment (such as at our clinic) or as an augmentation procedure (application after surgical repair or reconstruction).

How does PRP work?

Platelet-derived growth factor (PDGF): This is a protein that helps control cell growth and division, especially blood vessels. More blood to the site of a wound, more healing. PDGF has also been shown to provide a fertile ground for stem cell division – another reason for Stem Cell Therapy and PRP to be considered in tandem as a treatment.

  • Transforming growth factor-β is a polypeptide and important in tissue regeneration.
  • Insulin-like growth factor is a protein that is “insulin-like” similar to insulin. In this context of joint repair it is an important friend of cartilage cells.
  • Vascular endothelial growth factor (VEGF) an important protein that brings healing oxygen to damaged tissue blood circulation is damaged or inadequate.
  • Epidermal growth factor, which play key roles in tissue repair mechanisms.

These are the healing factors in PRP and the tools in the hands of an experienced physician can restore a knee, hip, shoulder, any joint back to pre-injury status.
Platelet-rich therapies are produced by centrifuging a quantity of the patient’s own blood and extracting the active, platelet-rich, fraction. The platelet-rich fraction is applied to the injured tissue; for example, by injection (as we do here).

  • PRP enhances rotator cuff repair following arthroscopic shoulder surgery.2
  • PRP enhances recovery after hip surgery.3
  • PRP helps you heel from Tommy John Surgery.4

In side-by side comparison studies doctors found:

  • PRP worked better than hyaluronic acid Acid injections.5

Doctors also found that PRP helped patients with other medical conditions that would make healing more difficult such as diabetes and heart disease.6

Most of the patients we see have had many failed medical procedures before they come to visit us, so there is of course skepticism about any therapy offered. When they ask us “will PRP work for me?” We tell them that this can be best answered following a physical examination and a discussion of realistic expectation. Each patient is unique so each answer will be so as well.

In the many years since our office started practicing Prolotherapy, we saw many patients who had Prolotherapy that did not work for them. The main reason was because of the variation in technique. Some doctors did Prolotherapy one way, other doctors did it another way, there was variations in injectable solutions offered, varying time frame between treatments, etc.

We find the same thing in Platelet Rich Plasma therapy and this IS Supported by research. There are many variations to PRP and the way it is performed by one doctor, may not be the same way it is performed by another doctor and without this standardization, the research cannot be clear. Read the findings:

“There are only a few studies of PRP treatment for cartilage on osteoarthritic knees. Different PRP products might be more or less appropriate to treat different types of tissues and pathologies.The clinical efficacy of PRP remains under debate, and a standardized protocol has not yet been established.”7

Even when PRP is introduced in a surgical setting as an aid to speed wound healing: “In the field of platelet concentrates for surgical use, most products are termed Platelet-Rich Plasma (PRP). Unfortunately, this term is very general and incomplete, leading to many confusions in the scientific database.”8

And in sports medicine: “Basic science and preclinical data support the use of PRP for a variety of sports related injuries and disorders. The published, peer reviewed, human data on PRP is limited. Although the scientific evaluation of clinical efficacy is in the early stages, elite and recreational athletes already use PRP in the treatment of sports related injuries. Many questions remain to be answered regarding the use of PRP including optimal formulation…9

PRP Treatments

When choosing Platelet Rich Plasma Therapy, many factors help determine the realistic outlook for success, including the experience of the doctor performing the treatment and experience in injectable therapies.

As we write in our emails to patients asking for more information – Platelet Rich Plasma therapy can be practiced differently from office to office. Where one office may be successful performing these treatments in one fashion, another office may have less than hoped for results.

Learn more about these treatments
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1. (Cochrane Database System Review Dec 23, 2013)

2. 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. [Epub ahead of print]

3. 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 15.

4. Hoffman JK, Protzman NM, Malhotra AD. Biologic Augmentation of the Ulnar Collateral Ligament in the Elbow of a Professional Baseball Pitcher. Case Rep Orthop. 2015;2015:130157. doi: 10.1155/2015/130157. Epub 2015 Jul 9.

5. 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]

6. 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

7. Gobbi A, Karnatzikos G, Mahajan V, Malchira S. Platelet-rich plasma treatment in symptomatic patients with knee osteoarthritis: preliminary results in a group of active patients. Sports Health. 2012 Mar;4(2):162-72.

8. Ehrenfest DM, Bielecki T, Mishra A, Borzini P, Inchingolo F, Sammartino G, Rasmusson L, Evert PA. In search of a consensus terminology in the field of platelet concentrates for surgical use: platelet-rich plasma (PRP), platelet-rich fibrin (PRF), fibrin gel polymerization and leukocytes. Curr Pharm Biotechnol. 2012 Jun;13(7):1131-7.

9. Mishra A, Harmon K, Woodall J, Vieira A. Sports medicine applications of platelet rich plasma. Curr Pharm Biotechnol. 2012 Jun;13(7):1185-95.


Rhone-Poulenc Rorer Physical Medicine & Rehabilitation Scholarship
Pan-Pacific Surgical Association Award for Outstanding Achievement in the Field of Research
Medical Research Award for Outstanding Achievement In the Field of Research

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