6 February 2011
I’ve been asked a lot about eccentrics which are a really big part of successful rehab from tendonosis, in climbers that’s usually Golfer’s or Tennis elbow. What to they do? How do they work to heal the tendon?
There are no definitive answers, in fact, right now the various teams around the western world researching such things are arguing more about this subject now than they were a few years ago. Here is a little discourse on where things are right now.
The protocol of eccentric wrist curls was first brought to prominence by two Canadian physiotherapists (Stanish and Curwin) who reported very impressive and consistent success rates with their tennis elbow patients using a protocol that stopped short of provoking pain in the tendon. Since then, lots of studies have followed over the past decade and a half, also generally reporting good or excellent results with various protocols. These days, the evidence is mounting that nearly everyone with elbow epicondyle tendinosis should be able to get rid of it without resorting to surgery, so long as they do the exercises (the hard bit!), do them right and eliminate the original cause (the other hard bit!).
Protocol - The various different research teams have, generally speaking, had success with three different protocols. One is to do 3 set of 10 reps daily, with a weight that stops just short of provoking pain throughout the exercise. A second is similar, but at an intensity that provokes a little pain in the final set. The third protocol, favoured in a string of papers by a Swedish researcher Hakan Alfredson and his team, is to do 3 sets of 15 reps daily at an intensity that causes mild pain throughout. Several other teams replicated good results using eccentrics only three days a week.
The allowance for pain during the rehab exercises runs counter to much of orthodox sports medicine, even from researchers in the same field. Far from being settled, it’s a question that is only just being opened in tendon research right now. However, the successful healing demonstrated by Alfredson’s protocol does speak for itself. Briefly, the idea behind it is that tendons suffering tendonosis (degenerative tissue changes) grow numerous and sensitive new nerve endings that serve as a protective measure to self limit the condition. In order to stimulate the tendon enough to grow new collagen and remodel immature scar tissue, the exercise must be a little painful. If the exercise progression is correct, a little exacerbation in the first few weeks should give way to steady pain ratings while the exercise intensity gradually goes up.
So why eccentrics only? Well a lot of researchers were unsatisfied with the rather simplistic explanation that this mode of contraction (lengthening under load) preferentially loaded the tendon rather than the muscle, preventing the muscle from getting strong ‘too quickly’. It’s true that muscles respond better to a combination of concentric and eccentric loading. What tendon strength responds best to is nearly impossible to research (would you let a man in a white coat train you for weeks, chop your bicep tendon out and pull it on a strain gauge until it snaps?).
One idea from Alfredson was that the eccentric loading breaks up the adhesions of disorganised scar tissue, as well as abnormal blood vessels and free nerve endings that proliferate in degenerative tendons, allowing both pain free stimulation and collagen maturation. There are various other ideas about how the tendon responds biochemically to eccentric loading related to growth factors, inflammatory processes and other very complicated processes of cellular messaging.
An intriguing new hypothesis is emerging that tendonosis might be down to underuse, rather than an overuse injury as it’s traditionally been perceived. Research into painful achilles and patellar tendons is suggesting that unequal distribution of loading exists within tendons that are chronically loaded at a certain joint range. Some areas are overworked and strained, other areas ‘stress shielded’ become atrophied and weak, and eventually strain as well. This lends weight to the importance of technique, training design and posture as being the direct causes of these injuries in at least a proportion of cases. There is some evidence that eccentric loading allows more even loading in the tendon, stimulating both the overused and underused portions in a way that allows them to recover normal collagen content and arrangement.
Whatever the underlying mechanism, there is quite convincing evidence that these exercises are the thing to do and seem to get through to even the most unresponsive tendons, except in a few extremely advanced cases where the tendon has been trashed so severely it literally turns to bone. Which protocol you choose largely comes down to experimentation I’m afraid, as no studies have compared the effectiveness of each in a reliable way. Personally, I’ve found that either pain free, or with a little pain worked on all three of my injured epicondyles (two now symptom free, one more recent injury well on the road to complete recovery).
People tend to fail at this by simply not disciplining themselves to do the exercises. Simple as that. I’ve read a couple of studies that demonstrated clearly that tennis elbow sufferers tended to recover much better on identical protocols if they were done with the physio there.
Remember that doing these exercises, although a gift to climbers who are suffering chronically, are only one part of the response. Unless your technique, posture, training all change to remove the reason you got injured in the first place, it’ll probably come back the minute you start trying to push your grade or training volume again.
This post is just a snippet about one aspect of elbow rehab. The above discussion should reinforce that healing a tendon for sport is a massive field and way more than a few blog posts. There is much more you should know - about the stretching, fitting the rehab in with climbing, and the detail of the changes to make in your technique, posture, training, lifestyle. Hence I’m writing the book. I know, I know, it’s not out yet… I’m working hard on it, but couldn’t resist a moment out to write this as I’ve been asked so many times…