Platelet rich plasma (PRP) has been in use for decades in various medical disciplines and recently has shown some promise in treating heel pain. This author discusses how PRP fits into his treatment regimen for chronic plantar fasciitis and offers a detailed guide to collecting and injecting PRP.
Plantar fasciitis is a very common condition of the heel. It is the most commonly diagnosed cause of heel pain and will affect about 1 million people each year.1 Plantar fasciitis has received a great deal of study over several decades. Most of these studies have focused on simplifying the diagnosis and the treatment of the disease. Over the years, we have learned much to narrow down the condition’s etiology and the treatment options that work best. The goal has always been to diagnose the problem properly and quickly return patients to daily life and activity.
Researchers have identified many conservative treatments for plantar fasciitis. Ninety percent of patients with plantar fasciitis will improve with conservative treatments.1 I have adopted a diagnosis and treatment protocol that depends on the acute or chronic and recalcitrant nature of plantar fasciitis. When a patient presents with heel pain lasting less than four to six months, I will implement protocol “A.” I will use protocol “B” for those with heel pain lasting more than four to six months.
When I suspect plantar fasciitis, after taking a complete history, the clinical examination will consist of a thorough neurological and musculoskeletal examination. This rules out any other less common causes of heel pain like tarsal tunnel syndrome. I obtain plain radiographs of bilateral heels. It is important to compare the radiograph with the contralateral heel to help rule out other pathologies. Evidence of a plantar calcaneal spur should only help the clinician determine the chronicity of the tightness of the ligament unless the spur is fractured. An ultrasound examination determines the thickness of the ligament. A measurement above 5 mm is considered pathologic. When I am satisfied that the diagnosis is plantar fasciitis and the pain has been present less than four to six months, I implement protocol A.
Protocol A. The patient will begin a strict two-week regimen including the following: rest from increased activity and an icing program of 10 to 15 minutes per treatment two to three times a day. The patient begins using an anti-inflammatory consistently for 10 to 14 days. I educate the patient on the extensive stretching program involving stretches of the calf and plantar fascia. Stretches before weightbearing out of bed or from long periods of rest are especially important. I educate patients on the use of appropriate shoe gear and advise them not to be barefoot or use sandals or flats even in the home. I also advise patients on the benefits of custom-molded orthotics in the treatment and prevention of plantar fasciitis. I recommend a cortisone injection at the initial visit in cases in which there is significant acute pain with weightbearing.
The patient returns in two weeks for re-evaluation. At this time, if there is improvement, the treatment continues. If there is no improvement or the condition is worse, I recommend a cortisone injection along with a four- to six-week course of physical therapy. If these conservative measures fail, use protocol B.
Protocol B. After four to six months of failed treatment or no treatment, one may consider the condition to be more chronic than acute. In these circumstances, order a magnetic resonance image (MRI) to evaluate the soft tissue and bone around the heel. In some cases, the MRI may reveal no pathology and no evidence of plantar fasciitis. When all other clinical and examination findings still point to a diagnosis of plantar fasciitis, it could still be present in the absence of MRI findings. This may be due to the lack of inflammation in a more chronic state that will not show on an MRI.
When I am confident in the diagnosis of plantar fasciitis, I present the patient with the option of performing more aggressive therapies: extracorporeal shockwave therapy (ESWT), platelet rich plasma (PRP) injection or Topaz Coblation (Arthrocare). I most often choose PRP.
The use of orthobiologics in the treatment of foot and ankle injuries, both in the clinical and surgical venues, is significantly increasing. The clinician and the surgeon continue to seek better ways to accelerate and mediate healing of bone and soft tissue while incorporating less invasive techniques.
The use of autologous PRP by foot and ankle specialists over the last few years has emerged in the forefront of biologic tools in this endeavor. Over the last four decades, researchers have looked at PRP for the treatment of tendon injuries, chronic wounds, ligamentous injuries, cartilage injuries, muscle injuries and bone augmentation (intraoperative fusions and fracture repair). There have been several studies investigating the efficacy of PRP and its applications.2 It has been in wide usage in the areas of spine surgery, wound healing, plastic surgery, oral and maxillofacial surgery, and orthopedic and podiatric surgery.2
The theory behind using PRP is that increased concentrations of autologous platelets, which yield high concentrations of growth factors and other proteins, will lead to enhanced healing of bone and soft tissue on a cellular level.
Platelet rich plasma is the concentration of platelets derived from the plasma portion of centrifuged or filtered autologous blood. This platelet rich solution can be an adjunct to healing, as in a fresh surgical fusion, or can reinstate healing as in the case of chronic tendon injuries. Platelet rich plasma and related products have different labels throughout the literature including: platelet-rich concentrate, platelet gel, preparation rich in growth factors (PRGF), platelet releasate and platelet-leukocyte-rich gel (PLRG).
Acquired PRP may or may not be activated by another product. Usually, we reserve PRP without activation for the treatment of tendons, muscles and other soft tissues. Platelet rich plasma activated into a gel or fibrin sealant is for use clinically and intraoperatively for tendon augmentation, wound healing and bone augmentation.
Essentially, PRP increases the concentration of platelets to an injured site. In an acute injury, platelets normally activate during the inflammatory phase to begin healing. The addition of PRP in the acute injury increases the concentration of platelets at the local tissue above the baseline. Chronic injuries that have failed conservative therapies presumably have ceased the inflammatory phase, have a paucity of platelets and a decrease in healing potential.
In these situations, PRP would provide two beneficial results. First, the simple act of the application of PRP through injection for tendon, ligament or muscle injuries will stimulate the tissue and restart the inflammatory process. This makes the chronic injury into a “new” acute injury. Second, the addition of autologous concentrations of platelets theoretically augments the healing process. This new injury now has a known starting point and one can place it in a controlled, post-injection environment (e.g. immobilization, bracing or non-weightbearing). During this time, restrict the use of anti-inflammatory medications and therapies so as not to reverse the desired effect.
To acquire autologous PRP, collect blood from the cubital vein. Determine the amount of blood acquired by the clinical application (treatment area) and desired concentration. Then separate the platelets from the plasma by means of centrifugation or filtration. Many different systems are available on the market today to obtain the PRP.
When using a simple centrifugation process, the collected blood spins down between five and 20 minutes, depending on the speed of the centrifuge and the concentration desired. There will be three relative layers of product in the tube: the plasma layer (platelets); the buffy coat layer (white blood cells); and the remaining blood products (red blood cells). The platelets are at the top of the tube. (There has been debate on the true concentrations obtained through simple centrifugation and the true output of a platelet-rich versus a platelet-poor product.) Then one collects the PRP from the tube using a syringe and 18-gauge needle, being careful not to collect any platelet-poor or red blood cells.
A similar method of collection uses an automated centrifugation process that separates the platelets from the whole blood and then automatically sends the product to a separate syringe using an infrared microprocessing sensor to differentiate between red blood cells and platelet-rich plasma. This type of system seems to lead to more accuracy and allows for more reproducible concentrations. There is presumably less error with less manual manipulation of the blood product through automated separation. One such device is the Magellan Autologous Platelet Separator System (Arteriocyte Medical Systems).
With either method, the tube that initially collected the blood must have an anticoagulant. The kits that come with the products usually already have tubes with anticoagulant or will come with a separate anticoagulant.
There have been limited studies examining the efficacy of PRP in the treatment of plantar fasciitis.
Barrett and Erredge investigated the use of PRP for plantar fasciitis in a small study.3 They used ultrasound of the fascia before and after treatment, and a patient pain scale to help determine efficacy. The patients were weightbearing in a walking boot for two days and then wore regular shoe gear with limited activity. They were restricted from using anti-inflammatories or other modalities. Researchers found that six of nine patients achieved complete resolution of symptoms after two months. One patient had resolution after a second injection. After one year, 77.9 percent of the patients had no symptoms. The study showed that ultrasound measurements of the thickness of the plantar fascia reduced following injection. It is unclear how long the study patients had their symptoms before treatment.
In a prospective work, Ragab and Othman looked at 25 patients with chronic plantar fasciitis who were treated with PRP.4 Over a mean follow-up period of 10.3 months, they found patients’ pain decreased from an average 9.1 to 1.6 on the Visual Analogue Scale after the injection with 88 percent of the patients completely satisfied and 60 percent with no functional limitations. They concluded that PRP is a safe and satisfactory method of treating plantar fasciitis.
Akşahin and colleagues compared the effectiveness of PRP injection versus corticosteroid injection for chronic plantar fasciitis.5 They studied 30 patients treated with PRP and 30 treated with steroids. Over a period of six months, they found that both patient groups had significant improvement in symptoms but there was no statistical difference between the groups. Taking into consideration the increased potential of complications with corticosteroid injection, the authors felt PRP to be safer and, at least, has the same effectivness as corticosteroid use for plantar fasciitis.
I have found promising results using PRP for those patients with chronic, recalcitrant plantar fasciitis. Patients who have failed conservative treatments (including RICE, functional foot orthotics, physical therapy and cortisone injections) after four to six months may be candidates for PRP.
Clinicians can confirm their diagnosis using ultrasound and/or MRI. Use a skin marker to identify the site of the most pain on palpation. Provide an initial anesthetic block at the site. Draw 60 cc of whole blood using a collection tube and butterfly needle. Calcium chloride activates the PRP. In order to keep the PRP in liquid form for injection, do not use thrombin.
Once the PRP is prepared, using the preferred method, clinicians can employ a 10 cc syringe and 22- or 18-gauge needle to inject the patient with 5 cc to 8 cc of PRP from the 60-cc whole blood collection. This yields a concentration that is a 10 to six times over baseline respectively. It is important to use a large gauge needle for injection. A 22-gauge or even 18-gauge needle is preferable. Smaller gauge needles may lyse the platelets. Of note, I have found that as the concentration increases, the patient’s post-injection pain increases.
Perform the injection with ultrasound guidance. Place several 0.25-cc pulsed injections, while peppering the needle, in the medial plantar fascial band starting at the point of maximum tenderness. In many of the patients, during the injection, one can appreciate the fibrosis of the ligament by a crepitus that is tangible and audible as the needle passes in and out of the fascial tissue. After completing the injection, perform continued peppering of the fascia, using the needle to further aggravate the tissue.
Restrict the patient from using any anti-inflammatories or modalities for up to three months after the treatment. Advise patients to use acetaminophen or narcotics for pain as needed. I have found better results with a post-injection protocol of a walking boot and crutches with no weightbearing for three to five days, and then walking in the boot for two to three weeks. Activity begins gradually around the third or fourth week in an athletic shoe and functional foot orthotic, and increases over a four-week period.
Some patients have benefited from a second injection when the first yielded only some relief in symptoms. One would give this injection about six weeks after the first one. Those patients who have no change in their symptoms after the first injection rarely benefit from a follow-up injection.
I have been using PRP over the last three years in the treatment of plantar fasciitis. The results have been increasingly promising with regard to decreased pain, increased activity, improved function, faster recovery and increased strength. The use of PRP in the clinical setting may be advantageous for its ease of use, relative availability, lack of side effects and improved tolerability in comparison to more invasive techniques.
Although the theory behind the use and effectiveness of PRP and some positive clinical evidence are promising, it is evident that additional well-designed prospective studies on PRP are needed to measure its true effectiveness in treating chronic foot and ankle pathology, specifically plantar fasciitis.
Dr. Soomekh is a Fellow of the American College of Foot and Ankle Surgeons and a Diplomate of the American Board of Podiatric Surgery. He is a faculty member at the University Foot and Ankle Institute in Los Angeles. Dr. Soomekh is also a Foot and Ankle Specialist for the Los Angeles Ballet.
1. Goff JD, Crawford R. Diagnosis and treatment of plantar fasciitis. Am Fam Physician. 2011; 84(6):676-82.
2. Mehta S, Watson JT. Platelet-rich concentrate: basic science and clinical applications. J Orthop Trauma. 2008; 22(6):432-438.
3. Barrett S, Erredge S. Growth factors for chronic plantar fasciitis. Podiatry Today. 2004; 17(11):37-42.
4. Ragab EM, Othman AM. Platelets rich plasma for treatment of chronic plantar fasciitis. Arch Orthop Trauma Surg. 2012; 132(8):1065-70
5. Akşahin E, Doğruyol D, Yüksel HY, Hapa O, Doğan O, Celebi L, Biçimoğlu A. The comparison of the effect of corticosteroids and platelet-rich plasma (PRP) for the treatment of plantar fasciitis. Arch Orthop Trauma Surg. 2012; 132(6):781-5.