Saturday, 30 July 2011

Part 2: Getting Rid of Tendinosis

No Inflammation?

Last week's blog took a look at the main differences between a more acute tendon injury (tendinitis) vs. a chronic tendon pain (tendinosis).  How exciting was that?

In case you missed it, or are too lazy the go back and read it (which I would be), the key difference to keep in mind is that while tendinitis is associated with inflammation, tendonosis is not.  Therefore, your typical icing and anti-inflammatory medication will simply not do the job with a chronic tendon injury.   

Then how do you get rid of your pain?  To get this answer, we will go back to our 2005 study published in the Journal of Medicine and Science in Sports.

This study took into consideration one of the most common types of chronic tendon pain- Achilles tendinosis.  A typical conservative treatment protocol for this type of injury often includes eccentric loading of the tendon.  Eccentric loading simple means taking your calve muscle from its shortened position to its longest position while under a load.  In other words, you would use your uninjured side to bring yourself onto your toes, and then slowly lower your heel to the ground using the injured side.  

 Here is a video of eccentric Achilles tendon loading:
This pilot study looked at 15 people who had not responded to previous conservative treatment (including rest, anti-inflammatory medication, orthotics, change in shoes, physical therapy).  Each of these individuals were so desperate that they were on a waiting list for surgery.  While they waited for their surgery, they completed one last ditch effort to rehab the painful tendon.  This is the protocol they followed:
  • 3x15 repetitions of the eccentric Achilles tendon exercise 
  • Repeated twice per day, 7 days a week, for 12 weeks 
  • Did not avoid going into pain 
  • If no pain was experienced, the number of reps were increased to create pain

After these 15 subjects completed the 12 week program, this is what they found:
  • There was a significant decrease in pain  (81.2 to 4.8 on the VAS- a pain scale) 
  • All 15 subjects were satisfied with their progress 
  • In a long term follow up, only 1 subject showed recurrence and subsequently required surgery

These are absolutely amazing results.  While medication, changes in shoes, and physical therapy could not touch the pain, this simple 12 week exercise program almost entirely eliminated it.  These results were consistent with what was observed in the author’s clinic as 90/101 painful Achilles tendons showed positive response to this protocol. 

Why Eccentric Loading?

First of all, why is it important to eccentrically load the tendon?  Why can you not concentrically load it (i.e. just stress the tendon by going up on your toes) instead?  In a recent study referenced within this article, it was shown that:
  •  81% of subjects were satisfied with their progress while eccentric loading
  • 38% of subjects were satisfied with their progress with concentric loading
So, to get the best results, go with eccentric.  If you try it yourself on your healthy Achilles tendons, even you will see that the concentric motion is smooth and easy when compared to the shaky motion of eccentrically loading the tendon.   

How does Eccentric Loading Change Tissue?
There is no definitive answer to how eccentric loading changes tissue.  There is, however, three theories:
  1. Increasing Tendon Strength:  The first logical theory is that by stressing the tendon, it will result in a stronger tendon.  However, if this is the reason why it works, then why would concentric loading not work?
  2. Decreasing the Perception of Pain: This theory makes a little more sense than the previous idea.  As mentioned in my previous article, one interesting difference associated with a chronically painful tendon is that there is an apparent lack of inflammation, and high levels of a neurotransmitter for pain- glutamate.  Thus, it leads to the idea that the tendon may no longer be damaged, but your nervous system is still interpreting pain originating from this area.  With the stepwise increase in repetitions with the eccentric loading protocol, you are consistently training your tendons to tolerate more loading and more pain.  This theoretically trains your nervous system to recognize and process only normal levels of pain from that tendon.
  3.  New Blood Vessels:  The final theory is associated with what is going on with blood vessels surrounding the chronically injured tendon.  As you may remember from my last article, there is an apparent decrease in blood flow within chronically injured tendons.  However, this also means that there is an increase in new blood vessels trying to penetrate the tendon along with associated nerves.  It is thought that these new nerves sprouting may be what is responsible for transmitting the inappropriately high levels of pain.  The theory is that the eccentric training regimen traumatically damages the blood vessels and subsequently decreases the amount of new nerves traveling into the tendon.
To test the 3rd theory, the sclorising agent Polidocanol was injected into the injured tendon.  This drug is normally used to treat itching, pain, and even varicose vessels.  It works by damaging blood vessels and causes them to shrink.  Thus, theoretically, if new blood vessels and the subsequent nerves were responsible for the pain experienced with tendinosis, then Polidocanol should stop the pain.  And, believe it or not, this is what was observed- both in the short and long term follow ups!
Not for Everybody 

First of all, it is important to note that this rehab protocol only seems to be effective when the painful portion is close to the muscle.  If it is close to the boney attachment, eccentric loading my not be helpful.  In this study, it was found that only 10 of 31 patients with insertional Achilles tendon pain were pain free and satisfied after their 12 weeks of rehab.  So, make sure you know what type of chronic tendon pain you have before you put your faith in eccentrics!


First of all, keep in mind that the tissue and cellular biology behind the rehab of chronic tendon pain is in its infancy.  This article simply outlines ideas with some interesting yet nonetheless limited supporting research.  So take it all with a grain of salt.

However, what you can conclusively know from this research is that if your tendon pain has not resolved with the normal rest and anti-inflammatory measures after an extended period of time, then:
  1. It is likely that your tendon is hurting for a reason other than inflammation (so it is time to lay off the rest and NSAIDs)
  2. Conducting an eccentric loading protocol that stresses the tendon into a point of pain is definitely worth trying (especially before you consider surgery) 

Alfredson, H. 2005. The chronic painful Achilles and patellar tendon: research on basic
biology and treatment. Scand J Med Sci Sports. 15: 252–259

Wednesday, 20 July 2011

Is Your Achilles Tendon (or other Tendon) Your Achilles' Heel?

The Painful Tendon

A tendon is a portion of connective tissue that links your muscle to bone.  These bands of tissue are prone to injury, and it is highly likely that you have experienced some form of tendon pain in your life.  Overuse shoulder injuries, tennis elbow, patellar tendinitis, and Achilles tendinitis are all common types of tendon pain that you may have encountered.  

RICE Principle- May not be effective for chronic tendon pain
But what exactly is going on with these damaged tendons?  Why do some symptomatic episodes get better in a matter of weeks, while others linger for months?  The answer comes down to what is happening at a cellular level, and where your pain is actually originating from.  These answers will not only surprise you, but it will drastically alter how you look at your injuries and how you manage them.  Surprisingly, your good friend, the “RICE” principle (Rest, Ice, Compress, Elevate), may not be as effective as you once thought. 

The Fallacy of Overuse

It is a well known fact that tendon pain originates from overuse, right?  The avid tennis player suffers from tennis elbow because he plays too much- it’s common sense.  It is common sense that appeals to my logic, but unfortunately it’s wrong (sometimes). 

In a 2005 review article published in the Journal of Medicine and Science in Sports, it was shown that the origin of chronic tendon pain likely does not come from overuse.  This paper references studies which described individuals who suffer from chronic tendon pain and who are also entirely inactive.  In addition, another study shows that physical activity was not correlated with the typical cellular changes that are associated with tendon pain.  The authors suggest, “that physical activity could be more important in provoking the symptoms than being the cause of the actual lesion” 

Thus, physical activity and overuse plays less of a roll than we once thought.  So should you be resting your injuries?  Maybe not, especially if it is a chronic problem.  

The Fallacy of Inflammation 

Popular consensus regarding the origins of tendon pain is as follows: the tendon is used so much that it becomes injured, inflammation follows, and subsequently pain is experienced.  This cascade is, in fact, fairly accurate, but for only half of the story.  While this sequence does describe what likely happens with an acute tendon injury, new research shows that chronically painful tendons show no signs of inflammation. 

The same 2005 paper describes how when histological studies were conducted on chronically painful tendons, normal levels of the inflammatory mediators called prostaglandins were found.  If inflammation was occurring, these prostaglandins would have been observed at high levels, but they were not.  In addition, genetic studies showed that there was no upregulation of the genes responsible for producing inflammation.  In other words, there were no signs of inflammation, and no signs of triggers for inflammation. 
These may be of no help with chronic tendon pain

Another more practically applicable study referenced in this paper looked at the use of piroxicam, an anti-inflammatory medication, in the treatment of chronic Achilles tendon pain.  Interestingly, it showed similar results to placebo, and now we know why!  There was no inflammation for the piroxicam to get rid of, so of course sugar pills were just as effective. 

This also brings us back to the “RICE” principal.  The ice, compression and elevation components are all designed to decrease inflammation.  But, if piroxicam was ineffective in treating a chronically painful tendon, it seems that these methods would also provide little help for the same reason. 

Tedinitits vs. Tendinosis 

If you have experienced some form of tendon pain and sought a diagnosis from a healthcare practitioner (or Dr. Google), it is likely that you have been labelled with tendinitis.  It is funny because generally speaking, medical jargon has a habit of labeling a patient’s affliction by simply restating what they experience- only in a fancy way.  So, if a patient comes in saying that they injured their tendon and they feel like it is inflamed, the healthcare practitioner would give them the diagnosis of tendinitis.  However, this tremendously insightful diagnosis literally means tendon inflammation (“tendin-” means tendon, “-itis” means inflammation).

 However, as we just learned, in a chronically painful tendon, there is no inflammation involved, so tendinitis is no longer appropriate.  To take the place of tendinitis, tendinosis is now used. 
Suffer from chronic wrist pain?  Inflammation may not be involved!

What’s Going on with Tendinosis 

Glutamate Molecule- the primary suspect with tendinosis pain
Research is somewhat in its infancy in understanding tendinosis, but there have been a few key discoveries.  First of all, the study referenced below shows that glutamate levels were much higher in chronically painful Achilles tendons compared to normal tendons.  Glutamate is a neurotransmitter that is highly associated with the perception of pain.  So, if you’re hurt, and you feel pain, glutamate is playing a role in getting that single from your injury to your brain.  So it seems with these cases of tendinosis, even though the chemical inflammation is gone, there still seems to be some form of neurological inflammation sending the perception of pain to your brain. 

A second interesting finding noted in this article is that there was higher levels of lactate in chronically painful tendons compared to normal tendons.  Lactate is what you accumulate in your muscles when you strenuously exercise.  This happens because there is not enough oxygen reaching the muscles to meet the imposed demands.  So, in the case of tendinosis, it is speculated that the high levels of lactate indicate decreased levels of oxygen reaching the area as a result of reduced blood flow. 

So, in summary, two things may be going on with tendinosis: (1) your painful tendon may not be getting enough blood flow and/ or oxygen, and (2) your brain may be getting a pain signal from the tendon despite a lack of inflammation. 

 What does this do to Treatment?

What these pieces of evidence show, first of all, is why you should not get discouraged if you currently have a chronic tendinosis.  If you have been resting, and trying to control the inflammation with medication and ice, it is no surprise that you have experienced limited success.  This paper shows us why the tried and true RICE principle of treatment for acute injuries simply does not apply to cases of tendinosis. 

So what can you do to help these cases of tendinosis?  The details will be in next week’s blog, but the answer almost seems counter-intuitive.  The two keys of treatment include; (1) increasing specific exercises that stress the damaged tendon (rather than resting), and (2) conducting the exercises into pain (rather than avoiding pain).  Stay tuned!


Alfredson, H. 2005. The chronic painful Achilles and patellar tendon: research on basic
biology and treatment. Scand J Med Sci Sports. 15: 252–259