Neuromechanical adaptations in achilles tendinosis

It is not just about the tendon. A perspective on asymmetry.

We are coming back to this important article again.
When you have a tendon problem, you have other problems. There is the muscle-tendon relationship, there is the CNS component, and there are the other muscles regionally within the related loaded chains. Because of these multiple integrated components, this "illustrates the human body's capacity to adapt to tendon pathology and provide the physiological basis for intervention or prevention strategies".
"If a component in the loop loses its integrity, the entire system has to adapt to that deficiency. "
We have discussed on recent TGG podcasts this important ability of a tendon to have sufficient stiffness, to be more precise, to produce sufficient stiffness. Degenerative tendons exhibit less stiffness and so when this issue is present, we move into the adaptive strategies of the entire system that was alluded to above. Adaptation begins; agonist, synergist, antagonist muscles, CNS, motor pattern adaptive patterns ensue.
It has been suggested by this study that these compensations are unilateral, on the affected side, thus driving asymmetrical neuromechanical adaptations.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4553058/

Knee hyperextension and delayed heel rise in an interesting sport, Racewalking.If you have been in practice long enough, you should know by now that in order to truly help an athlete you have to know their sport, the subtleties and the specifics.  Y…

Knee hyperextension and delayed heel rise in an interesting sport, Racewalking.

If you have been in practice long enough, you should know by now that in order to truly help an athlete you have to know their sport, the subtleties and the specifics.  You have heard us talk about premature heel rise off an on for years. Today, you must consider the opposite, delayed heel rise and the bizarre loading responses that come into the kinetic chains from such a behavior.

Racewalking is a long-distance event requiring one foot to be in contact with the ground at all times. Stride length is thus reduced and so to achieve competitive speeds racewalkers must attain cadence rates comparable to those achieved by Olympic 800-meter runners for hours at a time. Most people cannot truly appreciate how fast these folks are going.

There are really only two rules that govern racewalking:

1-The first rules states that the athlete’s trailing foot’s toe cannot leave the ground until the heel of the leading foot has created contact. 

2-The second rule specifies that the supporting leg must straighten, essentially meaning knee extension (and for some, terminal extension, ie. negative 5-10 degrees !) from the point of contact with the ground and remain straightened until the body passes directly over it. Again, essentially meaning full range knee extension for the entire stance phase of gait (early, mid and late midstance phases). 

Delated heel rise ?

Clearly some folks are going to take knee extension a little more literally. Look at the fella in the red and yellow. Can you say knee HYPER extension ? This is right knee anteriormeniscofemoral impingement looming on the horizon, this is an anterior compression overload phenomenon via the quadriceps. This is often met in this sport with the delayed heel rise that the sport seems to often drive. Prolonging the foot ground contact phase, attempting to abide by Rule#2, “the support  leg must straighten”, can lead to knee hyperextension if one is not careful. This will put a longer stretch load into the achilles and posterior compartment mechanism and this prolonged stretch-contract load can eventually lead to local pathology let alone in combination with the anterior knee compression we just eluded to. These folks will also be at risk for more anterior pelvic tilt, distraction of the anterior hip capsule-labral interval, unique hip extension and gluteal integration, and even possibly altered hip extension motor patterning driving abnormal loads into the hamstrings and low back.  Just imagine the changes in the hip flexor strategies in this scenario. 

To help your athletes, know their sport, know your normal biomechanics and know the pathologies when the rules of clean biomechanics are broken.

Today, on Rewind Friday, we will repost a more in-depth, with video, piece we did a few years ago on Race Walking. You may learn more about normal and abnormal gait than you think, today we translate some of the rules of the sport of race walking into deeper thoughts on gait mechanics.

Here is the link to our more in-depth video assessment and dialogue on the fascinating sport of race walking. If you have never truly looked at this sport before, you should enjoy this Rewind Post. (link).

- Dr. Shawn Allen

What are we listening to this week? The Plantaris…Thanks to Karly Foster of Twin Bridges Physiotherapy the: Physioedge podcast with David PopeImagine if you were able to dedicate a large portion of your life to the study of one individual mus…

What are we listening to this week? The Plantaris…

Thanks to Karly Foster of Twin Bridges Physiotherapy the: Physioedge podcast with David Pope


Imagine if you were able to dedicate a large portion of your life to the study of one individual muscle. That’s exactly what the main person interviewed here has done Dr. Kristof Spang from Sweden has done.  a lot of research on Achilles tendon tendinopathy.This podcast looks at the role of the plantaris muscle in mid tendon tendinopathy, with an emphasis on anatomy.

This muscle needs to be considered in recalcitrant cases of Achilles tendon apathy which of not respond to conservative means.

Dr Spang goes through some of the anatomical variations of attachment of the plantaris, with 10 to 20% attaching into the Achilles tendon. Since there seems to be at least nine different anatomical variations in attachment that can occur; this can often explain the variety of symptoms associated with plantaris issues.

The plantaris attaches from the lateral aspect of the femoral condyle downward to its insertion point within deli near its origin at the knee. The area of attachment distally can be between two and 5 mm and this “area attachment” may be part of the source of the pain. Phylogenetically the tendon attaches into the plantar fashia, similar to the palmaris. One theory is due to the small muscle size it may actually act as a proprioceptive sentinel for the knee and ankle. The peritendonous tissue may interfere with the gliding of the tendon in this is believed to be one of the ideologies of this recalcitrant problem.

Of the diagnostic imaging available, ultrasound seems to provide the most clues. In the absence of imaging, recalcitrant medial knee tendon Achilles tendon pain seems to also be a good indicator.

Our takeaway was that most often the problem seems to be had a conjoined area between the planters and Achilles tendon midcalf lead to most problems. Treatment concentrated in this area may have better results. If this is unsuccessful, surgery (removal of the plantaris, extreme, eh?)  may need to be considered.

Regarding specific tests for plantaris involvement, people who pronate seem to be more susceptible than those who supinate. This is not surprising since the tendon runs from lateral to medial it would be under more attention during predatory forces

It seems that plantaris tendonopathy  can exist separately from an conjoint tendinopathy and it may be that people of younger age may suffer from plantaris tendinopathy alone. This may indicate that the problem may begin with the plantaris and that the planters is actually stronger and stiffer than the Achilles!

It was emphasized that this condition only exists in a small percentage of mid Achilles tendon apathy patients. And that conservative means should always be exhausted first.


All in all, an interesting discussion for those who are interested in pathoanatomy. Check out part 2 in this series for more. 


link to PODcast: http://physioedge.com.au/physio-edge-041-plantaris-involvement-in-midportion-achilles-tendinopathy/

Custom orthotic or Sham for mid tendon achilles tendonopathy? It doesn’t seem to matter.This study prescribed eccentric calf exercises along with either a custom or “sham” foot orthosis for 140 people who were randomized as to whic…

Custom orthotic or Sham for mid tendon achilles tendonopathy? It doesn’t seem to matter.

This study prescribed eccentric calf exercises along with either a custom or “sham” foot orthosis for 140 people who were randomized as to which group got the real goods and which one did not.  A Victorian Institute Sports Assessment-Achilles questionairre was given at baseline, 1, 3, 6 and 12 months. No statistically significant difference between the groups.

Hmmm..

We wonder just what were the custom and sham like? When we use orthoses, we use full arch contact devices. Perhaps the type of orthosis makes a difference? What has been your experience?

Munteanu SE, Scott LA, Bonanno DR, Landorf KB, Pizzari T, Cook JL, Menz HB.  Effectiveness of customised foot orthoses for Achilles tendinopathy: a randomised controlled trial.
Br J Sports Med. 2015 Aug;49(15):989-94. doi: 10.1136/bjsports-2014-093845. Epub 2014 Sep 22.