Are PRP Injections Effective?

PRP therapy is not covered by most medical insurers. However, experts and physician groups are beginning to acknowledge PRP therapy’s potential to treat chronic tendinopathy. For example, the American Academy for Orthopaedic Surgeons describes the growing body of research as promising.¹Kelly FB. Platelet Rich Plasma. OrthoInfo. American Academy of Orthopaedic Surgeons. Last reviewed 2011. Accessed May 19, 2015. http://orthoinfo.aaos.org/topic.cfm?topic=A00648

Below are two examples of clinical studies examining PRP therapy

• In one of the largest studies²Mishra AK, Skrepnik NV, Edwards SG, Jones GL, Sampson S, Vermillion DA, Ramsey ML, Karli DC, Rettig AC. Platelet-Rich Plasma Significantly Improves Clinical Outcomes in Patients With Chronic Tennis Elbow: A Double-Blind, Prospective, Multicenter, Controlled Trial of 230 Patients. Am J Sports Med. 2013 Jul 3. [Epub ahead of print] PubMed PMID: 23825183. examining PRP, 230 patients with painful tennis elbow (lateral epicondylar tendinopathy) were treated with either a PRP injections or traditional treatments. After 24 weeks, nearly 84 percent of patients who received the PRP injections reported a 25 percent or greater reduction in pain, while 68.3 percent of the control group (p = 0.037) reported similar results.
• In another study, 99 tendons diagnosed with chronic tendinopathies were treated with PRP or autologous blood injections.³Harmon K, Drezner J, Rao A. Platelet rich plasma for chronic tendinopathy. Presented at the 2nd International Scientific Tendinopathy Symposium, Vancouver, BC, September 2012. As cited in Colberg RE, Mautner K, Platelet-rich plasma: An option for tendinopathy. Lower Extremity Review Magazine. http://lermagazine.com/article/platelet-rich-plasma-an-option-for-tendinopathy October 2013. Accessed August 18, 2015. Chronic tendinopathies included but were not limited to tennis elbow, jumper’s knee (patellar tendinosis), high hamstring tendinosis, Achilles tendinosis, and plantar fasciitis. Study patients had experienced symptoms for an average of 3 years before PRP therapy. Following therapy, the majority of patients reported some pain relief, and half the patients who received a leukocyte-poor PRP therapy reported to be mostly or all improved.

  See Is Heel Pain Caused by Heel Spurs or Plantar Fasciitis?

These studies demonstrate that—like other treatments for chronic tendon injuries—PRP does not offer a 100 percent reduction in pain for all patients. Rather, PRP therapy can be used as part of a larger treatment plan to reduce pain and improve function.

See What Is the Difference Between Tendonitis, Tendinosis, and Tendinopathy?

Less certain is whether or not platelet-rich plasma (PRP) injections are an effective treatment for other musculoskeletal problems, such as ligament injuries and osteoarthritis. While experts are hopeful and research is promising, more work needs to be done in this particular area.

PRP Does Not Work for Everyone

It is important to note that not all clinical studies provide support for using PRP.⁴Sandrey MA. Autologous growth factor injections in chronic tendinopathy. J Athl Train. 2014 May-Jun;49(3):428-30. doi: 10.4085/1062-6050-49.3.06. Epub 2014 May 19. PubMed PMID: 24840581; PubMed Central PMCID: PMC4080590. Some research suggests PRP injections work no better than a placebo treatment.⁵Dragoo JL, Wasterlain AS, Braun HJ, Nead KT. Platelet-rich plasma as a treatment for patellar tendinopathy: a double-blind, randomized controlled trial. Am J Sports Med. 2014 Mar;42(3):610-8. doi: 10.1177/0363546513518416. Epub 2014 Jan 30. PubMed PMID: 24481828.^,6de Vos RJ, Weir A, van Schie HT, Bierma-Zeinstra SM, Verhaar JA, Weinans H, Tol JL. Platelet-rich plasma injection for chronic Achilles tendinopathy: a randomized controlled trial. JAMA. 2010 Jan 13;303(2):144-9. doi: 10.1001/jama.2009.1986. PubMed PMID: 20068208.^,7Kesikburun S, Tan AK, Yilmaz B, Yaşar E, Yazicioğlu K. Platelet-rich plasma injections in the treatment of chronic rotator cuff tendinopathy: a randomized controlled trial with 1-year follow-up. Am J Sports Med. 2013 Nov;41(11):2609-16.doi: 10.1177/0363546513496542. Epub 2013 Jul 26. PubMed PMID: 23893418.^,8de Vos RJ, Windt J, Weir A. Strong evidence against platelet-rich plasma injections for chronic lateral epicondylar tendinopathy: a systematic review. Br J Sports Med. 2014 Jun;48(12):952-6. doi: 10.1136/bjsports-2013-093281. Epub 2014 Feb 21. Review. PubMed PMID: 24563387. Even in studies that do provide evidence that PRP works, not all patients benefit. And while many studies show PRP therapy is low risk, at least one study reports that patients’ symptoms worsened following PRP treatment.⁹Bowman KF Jr, Muller B, Middleton K, Fink C, Harner CD, Fu FH. Progression of patellar tendinitis following treatment with platelet-rich plasma: case reports. Knee Surg Sports Traumatol Arthrosc. 2013 Sep;21(9):2035-9. doi: 10.1007/s00167-013-2549-1. Epub 2013 Jun 1. PubMed PMID: 23728418.

It may be that PRP therapy, like other treatments for damaged tendons, works for some people but not for others, or works best in conjunction with other treatments, such as physical therapy.

PRP as Part of a Comprehensive Treatment Plan

Most doctors do not consider PRP injections a stand-alone treatment. Instead, the injections are one element in a multi-faceted rehabilitation treatment plan that may include:

• Rest from painful activities
• Strengthening, especially eccentric exercises
• Stretching
• Cold or heat therapy (applying cold-packs or hot-packs)
• Anti-inflammatory medication , though patients are advised to use these medications judiciously, because they can be detrimental to the production of collagen, an essential component of tendon tissue.
• Electrical muscle stimulation (also known as EMS or Electromyostimulation)

General guidelines for rehabilitation after PRP treatment exist,¹⁰Krogman K, Sherry M, Wilson J, et al. Platelet Rich Plasma Rehabilitation Guidelines. UW Health Sports Rehabilitation. http://www.uwhealth.org/files/uwhealth/docs/sportsmed/sports_med_PRP.pdf Updated April 2014. Accessed August 18, 2015. and may vary depending on the condition. Usually, these treatments are performed under the supervision of a licensed physical therapist or licensed athletic trainer.