One of the most difficult problems to treat in the clinic is chronic pain related to tendinopathy.  More specifically, the Achilles tendon, patella tendon and elbow extensors often present challenges for doctors and clinicians alike when it comes to effectively reducing or resolving pain.  Over time, people develop chronic inflammation or even little tears in the muscles running up to the lateral epicondyle.

tennis-elbow

There have been many studies done looking at PRP over the past 5-10 years.  The debate continues, however, with respect to its efficacy in terms of results, especially given the fact that patients must currently pay out of pocket for the procedure.  I have written two earlier posts on PRP that you may be interested in reading as a back drop for this one:

2011 - An Update on Platelet Rich Plasma

2011 - Platelet Rich Plasma and Rotator Cuff Repairs

Currently, my approach to treating these injuries involves an approach focused on soft tissue mobilization via instrument assisted soft tissue mobilization, stretching, strengthening and a trial of iontophoresis in most cases.  We also offer dry needling at our facility and this has been effective in reducing pain.  I will talk more about this point later as it relates to the prospective multi-center trial summarized by Mishra et al. in the February 2014 edition of the American Journal of Sports Medicine.

Before I get to the study, I thought it would be pertinent to provide some straightforward information on PRP as it is a question that comes up with patients on a regular basis.  Essentially, the process is as follows:

1. Collect 30-60 ml of blood form the patient’s arm

2. Blood is then placed in a centrifuge.  The centrifuge spins and separates the platelets from the rest of the blood.

3.  A syringe is then used to extract 3-6ml of the platelet-rich plasma

4. The concentrated platelets are then injected into the elbow (or site being treated)

clinical-prp-injection

The thought behind PRP is to increase the growth factors up to 8x, which promotes temporary relief and stops inflammation. The question is how successful and cost effective is this process?  Consider that opting for surgery will run between $10,000 and $12,000 figuring in costs for the surgeon, hospital/surgery center, anaesthesiologist, etc.  PRP injections will cost upwards of $1000, so one would think that would be a favorable option for insurers if surgery could be averted.

What about cortisone injections?  They are widely used as a survey of 400 members of the American Academy or Orthopedic Surgeons found that 93% had administered a corticosteroid injection for lateral epicondylar tendinopathy.  According to Bisset et al (Br  Med J 2006) and Lindhovius et al (J Hand Surg Am 2008) cortisone injections do provide short term pain improvements but also result in a high rate of symptom recurrence.  There are other potentially harmful side effects from injections including: reduced collagen synthesis, depletion of human stem cells, depigmentation, and enhancement of fatty and cartilage like tissue changes that can lead to tendon ruptures.

So, the big question is whether or not tendon needling with PRP is an effective treatment option for chronic tennis elbow suffers. Mishra and his colleagues set out to examine this with a double blind, prospective, multi-center randomized controlled trial of 230 patients.  In the study, the patients were teated at 12 different facilities over 5 years.  All patients had at least 3 months of pain/symptoms and failed conservative treatment.

The PRP was prepared from venous whole blood and contained both concentrated platelets and leukocytes. After receiving a local anesthetic, all patients had their extensor tendons needled with (n = 116) or without PRP (n = 114).  A successful outcome was defined as 25% or greater improvement on the visual analog scale for pain (VAS).  Pain was measured at baseline, 4, 8, 12 and 24 weeks with resisted wrist extension.

Results

  • At 12 weeks (n = 192) PRP group reported a 55.1% improvement in pain versus control group at 47.4%
  • At 24 weeks (n = 119) PRP group reported a 71.5% improvement versus 56.1% in the control group
  • At 12 weeks, elbow tenderness was reported in 37.4% of the PRP group and 48.4% in the control group
  • At 24 weeks, elbow tenderness was reported in 29.1% of the PRP group versus 54% in the control group
  • Overall success rates were 83.9% in the PRP group and 68.3% in the control group at 24 weeks
  • No significant complications in either group

Other key takeaways from the study

  1. Both groups got better over time.  There were no significant differences in the patient related elbow questionnaire (PRTEE) as both groups showed comparable improvements, but the PRP group showed more improvement over baseline.
  2. Some weaknesses of this current study are the fact that all patients did not make it to the 12 and 24 week follow-up.  Additionally, longer follow-up (such as 1 and even 2 year intervals would provide a clearer picture of overall symptom relief and response to treatment intervention).
  3. There was no standardized rehab protocol implemented in this study namely because the authors felt it was too hard to ensure compliance across so many different centers.  This begs the question of how additional measures such as routine strengthening, stretching and soft tissue work may have further aided in recovery.
  4. One of the more promising things to come from the study is that results can be reproduced with blinding of the process and standardization of the PRP preparation utilizing the same device and injection protocol.  This holds some promise for looking at more globally accepted pathways to deal with the general population assuming the type 1 PRP used in this trial is chosen
  5. For physical therapists who are able to administer dry needling, this study seems to suggest that there may be inherent value in needling the tissue alone, however, the authors caution that that the clinical importance of this may be limited given that 54% of the control group still reported significant tenderness at 6 months compared to the PRP group at 29%.  A study by Rha et al (Clin Rehabil 2012) did conclude that PRP was more effective than dry needling for rotator cuff pathology.  Certainly, dry needling could be considered a preliminary step before opting for PRP treatment.

Future directions

It still remains unclear exactly why and how PRP works.  It has been pustulated that it somehow improves tendon physiology, but large studies using ultrasound have yet to show significant structural changes with PRP.  Patients must continue to embrace the fact that lateral epicondylar tendinopathy generally involves a protracted healing process and will not respond quickly or appropriately without relative rest and activity modification coupled with careful and deliberate treatment.  There must be an appropriate balance between stress and recovery.

I am cautiously optimistic about the use of PRP moving forward.  I want to believe, but still need to see more before I become a full fledged advocate.  With that said, I do endorse it over jumping right to surgery.  Keep in mind that according to Cohen and Romeo, 28% of patients complain of persistent symptoms and 9% report moderate to severe pain 5 years after surgery (Hand Clin. 2009).  Like I tell my patients, there is no such thing as routine or simple surgery.  Studies have been initiated that look at augmenting tissue repair with PRP, and it will be interesting to see how those results come out.

In the meantime, there is enough promising information in the literature to consider PRP in the treatment of chronic pain related to tendinopathy.  My advice is to consult a knowledgeable physical therapist and seek effective conservative care first, and this is usually the first step the MD will use.  Do not expect immediate results and know that time may be your ultimate healer.  I found that to be the case personally as it took about 7 months for mine to resolve with a treatment predicated on activity modification, soft tissue therapy, stretching and eccentric exercise.

So, remember there is no quick fix for this issue, including PRP.  Do not be fooled into thinking cortisone will solve the problem either.  It may reduce pain/inflammation, but addressing the tissue damage is a must.  With respect to PRP, it exists as a viable option when PT fails seems to assist and facilitate the healing process provided we as humans do not perpetually sabotage our own healing process with destructive repetitive activity.

Reference article: Mishra et al. Efficacy of platelet-rich plasma for chronic tennis elbow. Am J Sports Med. 2014;42(2):463-471.