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If a damaged or injured tendon fails to heal with rest and conservative therapy, a clinician may recommend injecting platelet-rich plasma (PRP). Many experts believe that the natural healing properties found in platelets and plasma facilitate healing and repair in damaged tissues.

When treating a damaged tendon with platelet-rich plasma for instance, the clinician injects PRP directly into the affected area with the goal to:

• Reduce pain

• Improve joint function

• Repair damage to tendon tissue

While a lot of research has been done in recent years, more large-scale clinical studies are needed before scientists can know exactly if and how PRP helps patients who have tendinopathy and related conditions.

Tendinitis, Tendinosis, and Tendinopathy Pain

Tendons are soft tissues that connect muscle to bone, and their degeneration may be caused by multiple factors, such as past injuries, ageing, stress, and overuse. Tendon damage is commonly referred to as tendinitis, tendinosis, or tendinopathy. Tendinitis is an inflammatory condition, but research has shown that most tendon injuries do not exhibit inflammation. Rather, the primary problem appears to be a breakdown of the structural composition (e.g. the amount of essential collagen a tendon contains), strength, and stability. In some cases this degeneration results in chronic pain, disability, or tendon tears.

How Does PRP Therapy Relieve Joint Pain?

Experts predict that the PRP has the ability to:

• Stimulate healing, including stimulating the production of collagen, which is an important component of tendon and ligament tissue

• Contain proteins that alter a patient’s pain receptors and reduce pain sensation

What Are Platelets and Plasma?

Platelet-rich plasma is derived from blood. A blood sample from the patient is processed using medical equipment to produce a therapeutic injection that contains plasma with a higher concentration of platelets than is found in normal blood.

• Platelets are a normal component of blood, just like red and white blood cells. Platelets release substances called growth factors and other proteins that regulate cell division, stimulate tissue regeneration, and promote healing. Platelets also help the blood to clot.

• Plasma refers to the liquid component of blood. It is mostly water but also includes proteins, growth factors, nutrients, glucose, and antibodies, among other components.

How Is PRP Made?

The most common way to prepare PRP involves centrifuging a patient’s blood sample. A vial of blood is placed in a centrifuge, where it is spun at intensely high speeds. The spinning causes the blood to separate into layers:

• Red blood cells, approximately 45 percent of blood, are forced to the bottom of the vial.

• White blood cells and platelets form a thin middle layer, called a buffy coat, which comprises less than 1 percent of the centrifuged blood.

• “Platelet-poor” plasma, or plasma with a low concentration of platelets, makes up the remaining top layer, about 55 percent of the centrifuged blood sample.

Once the centrifugation process is complete the clinician will remove the vial from the centrifuge, extract the necessary blood components for PRP, and prepare the PRP solution for injection.

Like all treatments 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. 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 as Part of a Comprehensive Treatment Plan

PRP 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 and may vary depending on the condition. Usually, these treatments are performed under the supervision of a licensed physical therapist or licensed athletic trainer.

Advantages of Platelet-Rich Plasma (PRP) Therapy

People diagnosed with tendinosis or tendinopathy might consider PRP therapy for several reasons:

• Other traditional treatments may fail to provide adequate relief.

• PRP is derived from the patient’s own blood, and the injections carry few risks.

• Other treatments have side effects or drawbacks:

◦ Physical therapy is often effective but does not always satisfactorily relieve symptoms or improve function.

◦ Cortisone injections can temporarily reduce pain; however, symptoms can recur. In addition, tendons exposed to cortisone may weaken, making the injury worse.

◦ Non-steroidal anti-inflammatory medications (NSAIDs) such as aspirin and ibuprofen may effectively reduce pain, but habitual use can cause or aggravate stomach problems, blood pressure, and heart problems.

◦ Minor surgeries to treat tendon damage and degradation, such as arthroscopic debridement, do not always work, tend to carry more risks, and have longer recovery times.

• While more clinical studies are needed, the research so far seems to be promising.

Because there is no surefire way to treat damaged tendons, and because PRP injections carry few risks, many clinicians believe that PRP therapy is worth trying.

Patients should keep in mind that PRP is not a cure-all, and it may be best used in combination with nonsurgical treatments and lifestyle changes, such as physical therapy, weight loss, taping, and NSAIDs.

Suggested Indications for Treating Tendons with PRP

Experts have not developed definitive criteria for deciding when and to whom to recommend PRP injections, but some suggestions are below:

• Tendon pain affects daily activities

• Physical therapy has not adequately improved function and reduced pain

• Other non-surgical treatments have failed or been eliminated

• The patient is sensitive to anti-inflammatory medications (NSAIDs) such as ibuprofen; finds medications do not provide adequate pain relief; or wants to avoid long-term use of medications.

• Surgical treatment is not optional or not desired.

Platelet-rich plasma injections may not be recommended for the most severe cases of tendinosis or tendinopathy, these cases may be reverted for surgical option.

Contraindications for PRP Therapy

Platelet-rich plasma injections may not be appropriate for a patient who:

• Has a medical condition that could worsen or spread with injections, such as an active infection, a metastatic disease, or certain skin diseases

• Has certain blood and bleeding disorders

• Is undergoing anticoagulation therapy (and cannot temporarily suspend treatment)

• Is anaemic

• Is pregnant

Additionally, patients who have an allergy to cow products should tell their doctor. These patients could experience an allergic reaction if the platelet-rich plasma is combined with an additive called bovine thrombin, which is derived from cows.

Pre-Injection Precautions

The American Academy of Orthopaedic Surgeons recommends patients avoid or discontinue certain medications prior to injection:

• Avoid corticosteroid medications for 2 to 3 weeks prior to the procedure

• Stop taking non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or aspirin (low dose, 81mg, aspirin may be permissible), or arthritis medications such as Celebrex, a week prior to the procedure

• Do not take anticoagulation medication for 5 days before the procedure (done only under doctor supervision)

In addition, patients are advised to drink plenty of fluids the day before the procedure. Some patients may require anti-anxiety medication immediately before the procedure.

Platelet-Rich Plasma Injections, Step-by-Step

This is an in-office procedure that involves a blood draw, preparation of the PRP, and the injection:

• Blood is drawn from a vein in the patient’s arm into a syringe (15 to 60mL, or 0.5 to 2 ounces, or more may be needed).

• The blood is processed using a centrifuge machine.

• A doctor or technician prepares the centrifuged platelet-rich plasma for injection.

• The affected joint area is cleansed with disinfectant such as alcohol or iodine.

• The patient is asked to relax; this will facilitate the injection and also can make the injection less painful.

• Using a syringe and needle, the doctor injects a small amount (often just 3 to 6 mL23 ) of platelet-rich plasma into the affected tendon.

• The injection area is cleansed and bandaged.

The platelet-rich plasma typically stimulates a series of biological responses, including inflammation, so the injection site may be swollen and painful for about 3 to 5 days.

After the PRP Injection: Immediate Follow-up Care

Platelet rich plasma injections may cause temporary inflammation, pain, and swelling. Patients are often advised to take it easy for a few days and avoid putting strain on the affected joint.

A doctor may recommend that a patient:

• Avoid anti-inflammatory pain medication; the doctor may prescribe or recommend another pain medication.

• Use crutches, wear a brace, and/or wear or sling to protect and immobilise the affected joint.

• Apply a cold compress a few times a day for 10 to 20 minutes at a time to help decrease post-injection pain and swelling. (Some doctors may recommend a warm compress instead.)

If the patient does not have a physically demanding job, he or she can usually go back to work the next day. Patients can usually resume normal activities a few days after the injections, when swelling and pain decrease. Patients should not begin taking anti-inflammatory medications until approved by the doctor.

Physical therapy

The patient will likely be prescribed post-injection physical therapy. A licensed physical therapist can teach the patient exercises that build and maintain joint strength and flexibility.

Efficacy of Platelet-Rich Plasma Injections

PRP has been used in surgeries to promote cell regeneration since 1987 and a growing body of evidence shows it is a viable treatment for tendinosis. Not until recently, though, have experts researched and debated whether or not platelet-rich plasma (PRP) injections are an effective treatment for osteoarthritis.

Nearly all of the research investigating the use of PRP to treat osteoarthritis and other cartilage defects has been done since 2000, and the vast majority of research articles on the topic have been published since 2010.

Not all studies support the use of PRP to treat osteoarthritis; however, experts who have reviewed the existing body of research believe the evidence is largely encouraging and merits further investigation.

Knee Osteoarthritis Treated with PRP

Two clinical studies that examine PRP to treat knee arthritis are described below.

1 One study, published in 2013, involved 78 patients with osteoarthritis in both knees (156 knees). Each knee received one of three treatments: 1 PRP injection, 2 PRP injections, or 1 placebo saline injection. Researchers evaluated the subjects’ knees 6 weeks, 3 months, and 6 months after injection. Researchers found:

◦ Knees treated with 1 or 2 PRP injections saw a reduction in pain and stiffness as well as improvement in knee function at 6 weeks and 3 months.

◦ At the 6-month mark positive results declined, though pain and function were still better than before PRP treatment.

◦ The group that received placebo injections saw a small increase in pain and stiffness and a decrease in knee function.

2 A second, smaller study examined patients who had experienced mild knee pain for an average of 14 months. Each arthritic knee underwent an MRI to evaluate joint damage and then received a single PRP injection. Patients' knees were assessed at the 1 week, 3 month, 6 month and 1 year marks. In addition, each knee underwent a second MRI after one year. Researchers found:

◦ One year after receiving a PRP injection, most patients had less pain than they did the year before (though pain had not necessarily disappeared).

◦ MRIs showed that that the degenerative process had not progressed in the majority of knees.

3 While knee cartilage did not seem to regenerate for patients, the fact that the arthritis did not worsen may be significant. Evidence suggests that an average of 4 to 6% of cartilage disappears each year in arthritic joints.

Platelet-Rich Plasma (PRP) Therapy for Arthritis

A growing number of people are turning to PRP injections to treat an expanding list of orthopaedic conditions, including osteoarthritis. It is most commonly used for knee osteoarthritis, but may be used on other joints as well.

When treating osteoarthritis with platelet-rich plasma, a clinician injects PRP directly into the affected joint. The goal is to:

• Reduce pain

• Improve joint function

• Possibly slow, halt, or even repair damage to cartilage

Here at Dynamic Regenerative Medicine in Solihull and Birmingham we believe in the beneficial effects of PRP treatment and offer this treatment for a wide range of conditions whether it be related to sports injury of general occupation.

For further information please contact us or 01564 330 773.

PRP Therapy for Chronic Tendon Injuries References

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2 The International Cellular Medical Society. Guidelines for the Use of Platelet Rich Plasma. Adopted 2011. Accessed August 15, 2013.

3 ECRI Institute. AHRQ Healthcare Horizon Scanning System Potential High Impact Interventions: Priority Area 01: Arthritis and Nontraumatic Joint Disease. (Prepared by ECRI Institute under Contract No. HHSA290201000006C.) Rockville, MD: Agency for Healthcare Research and Quality. June 2012.

4 Graziani F, Ivanovski S, Cei S, Ducci F, Tonetti M, Gabriele M. The in vitro effect of different PRP concentrations on osteoblasts and fibroblasts. Clin Oral Implants Res. 2006 Apr;17(2):212-9. PubMed PMID: 16584418.

5 Taralyn M. McCarrel, Tom Minas, Lisa A. Fortier; Optimization of Leukocyte Concentration in Platelet-Rich Plasma for the Treatment of Tendinopathy. The Journal of Bone & Joint Surgery. 2012 Oct;94(19):e143 1-8.

6 Dohan 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. Review. PubMed PMID: 21740379.

7 Kelly FB. Platelet Rich Plasma. OrthoInfo. American Academy of Orthopaedic Surgeons. Last reviewed 2011. Accessed May 19, 2015.

8 Mishra 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.

9 Harmon 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. October 2013. Accessed August 18, 2015.

10 Sandrey 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.

11 Dragoo 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.

12 de 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.

13 Kesikburun 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.

14 de 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.

15 Bowman 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.

16 Krogman K, Sherry M, Wilson J, et al. Platelet Rich Plasma Rehabilitation Guidelines. UW Health Sports Rehabilitation. Updated April 2014. Accessed August 18, 2015.

17 The International Cellular Medical Society. Guidelines for the Use of Platelet Rich Plasma. Adopted 2011. Accessed August 15, 2013

18 Shute, N. Platelet Rich Therapy Gains Fans, But Remains Unproven. National Public Radio. June 14, 2014. Accessed August 18, 2015.

19 Biologic Orthopedic Society. 2013. LinkedIn. Discussion Page: What should the total reimbursement be to a provider for platelet rich plasma (PRP) procedure including any cost of goods and services and the office visit? Retrieved September 24, 2013.

20 Emory Healthcare. Platelet Rich Plasma. ©2015. Accessed August 18, 2015.

21 Santo F. Martinez, M.D. Practical Guidelines for Using PRP in the Orthopaedic Office. American Academy of Orthopaedic Surgeons. Published September 10, 2010. Accessed November 15, 2012.

22 Kaux J-F, Bouvard M, Lecut C, et al. Reflections about the optimisation of the treatment of tendinopathies with PRP. Muscles, Ligaments and Tendons Journal. 2015;5(1):1-4.

23 Halpern B, Chaudhury S, Rodeo SA, Hayter C, Bogner E, Potter HG, Nguyen J. Clinical and MRI Outcomes After Platelet-Rich Plasma Treatment for Knee Osteoarthritis. Clin J Sport Med. 2012 Dec 12.

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