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Effect of Gastrocnemius at the knee joint

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Old 13th February 2010, 08:28 AM
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Default Effect of Gastrocnemius at the knee joint

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Hi I´ve been geeting into lots of shall we say discussions with Musmed aka Paul Conneely over the effect of the Gastrocnemius at the knee and ankle, and what its main roles are in another thread.

http://www.podiatry-arena.com/podiat...ad.php?t=43688



Here is the highlights-lowlights of that discussion from us with a couple from Kevin Kirby.

Quote:
Originally Posted by m weber View Post
The below was written by Simon Spooner and has got me thinking...



Now Simon was discussing a study protocol (http://www.podiatry-arena.com/podiat...ad.php?t=39056 ) In this thread.

Now as we know the Gastroc and soleus main job is as a plantarflexors thru pull on the achillies tendon on the posterior calc. There will depending on the position of the subtalar joint axis be a pronatory, supinatory or no movement when considering STJ motion.

Now the thread was discussing medial skive orthtoics so that indicates to me that the patients have a medial deviated axis. If we work with this idea in mind whether its often seen in the real world or not.

So the STJ axis is medially deviated,

Here are two quote to consider about an axis from Simon Spooner


and Eric Fuller


Note when using achillies tendon I also include the muscles gastroc and soleus and their action of contraction and excentic contraction

Now as stated the pull of the achillies tendon can cause 3 different motions at the STJ, if the STJ is medially deviated the motion around the STJ axis will most likely be an external pronation moment. Now the the insertion point is lateral to the STJ axis the load on the achillies tendon will be less, it has a mechanical advantage. ie the natural motion of the foot is pronation the achillies is at a mechanical advantage.

So if we use a medial skive device as part of our treatment plan we maybe adding to the load of the achillies tendon.

As the medial skive will cause an external STJ supination moment the axis will also deviate laterally, which may mean either a shorter level arm or the insertion point of the achillies will be medial to the STJ axis which would then mean the muscle must help "control" the natural motion of pronation of this patient and the type of work will change and if the load placed on it by the body is too much an increase in symptoms.

Now this may be obvious to most and if so sorry for being a bit dense but I could not find this discussed anywhere and if I´m wrong in my revolution of sorts let me know.

The opposite would work for a lateral deviated axis as well.

I also though that this might be a good discussion to get the orthotics consensis project going again ?

What do others think?
Quote:
Originally Posted by musmed View Post
Dear Michael

May I suggest that you anatomy is not quite correct and thus your assumptions follow that line.
The soleus is inserted into the medial posterior aspect of the calcaneum and is thus a supinator of the foot and not a plantar flexor as its primary role.
The reason why I say the soleus is a supinator of the foot is because almost nobody has a mobile subtalar joint.
As I have posted many times, why is OA to the subtalar joint a very rare event if there is no history of a fracture to the joint line?
Regards from bleak Stratford UK
Musmed
Paul conneely
Quote:
Originally Posted by musmed View Post
\Dear MichaelNo2.May I be so bold as to suggest that the gastroc is a knee extender as its primary role.The next few patients with OA of the knee check the strength of the gastroc.It will be weaker on the OA side.This is to compensate for the joint changes.Oh I can see some sunPaul Conneely
Quote:
Paul you keep saying these thing and most people ignore your comments. I will put these in with the below comments which you have made which make no sense and kind of make me laugh and cry at the same time.
Quote:
Quote:
Originally Posted by musmed
I have examined well over 100,000 feet and I can tell you that less that a few percent have any motion at the subtalar joint. I am certain that the several hundred whom I have taught will agree with me.
The main motion occurs between the calcaneum and the fat pad and the fat pad and the skin and the skin and whatever it comes into contact with. These three 'joints' are never thought about let alone discussed.

Regards
Paul C
But please don´t comment here make a new thread the stj dosen´t move or something like that or the Gastroc is not a plantarflexer
Quote:
Originally Posted by musmed View Post
Dear Mr. W
I like the red writing, is Valentine's day in the air.
I must admit it looed rather calming (as red is) just look at the McDonald's colours. why do you think they use these colours.
I hate to tell you this, but the gastroc is the strrongest knee extensor (just sit for any USA sports medicine exam)
and there are another 17 beleivers in the UK.

Regards
from Sunny Australia
Paul C
Quote:
Originally Posted by Kevin Kirby View Post
Michael:

The gastrocnemius (gastroc) muscle is definitely an ankle joint plantarflexor in open kinetic chain. However, since the gastroc is also a knee joint flexor, its function during closed kinetic chain is more complex. What these researchers did was to electrically stimulate the gastroc and saw that ankle joint dorsiflexion increased in 4 of 5 subjects. What this means was that the ankle joint dorsiflexion moment increased as a result of increased knee flexion since the body weight was now pushing the tibia harder forward at the knee which, in turn, increased ankle joint dorsiflexion moment. In other words, the increase in ankle joint plantarflexion moment from gastroc contraction pulling on the posterior calcaneus was less than the increase in ankle joint dorsiflexion moment from gastroc contraction that caused the knee to buckle, the tibia to be driven forward, thereby increasing ankle joint dorsiflexion. Whether this is physiological and not simply an experimental artifact of having an important stance phase muscle suddenly shocked by electricity and the individual's central nervous system responding with an unphysiologic response, still remains to be seen.

I believe that if you look closely at the excellent forward dynamics research by Rick Neptune from over the years, it becomes very clear that the gastroc is an important plantarflexor of the ankle, not the ankle joint dorsiflexor that some authors have hypothesized.
Quote:
Originally Posted by m weber View Post
Where are all the papers with this evidence for the fact that the Gastroc in now not a knee flexor but a knee extensor, I´m sorry Paul I´m not going to take your word for it cause it still makes no sense. Have you read all the paper that have been posted in the last few days about the role of the Gastroc and have you also read the problems with the research completed discussed above here ? If you read Kevin Kirby´s post below, the 1st 2 lines in blue for you today.
Quote:
Originally Posted by musmed View Post
Dear All
The late Vladamir Janda, the father of rehabilitation used to say that when looking at movement in the upper limb, look at agonists antagonists.
When looking in the lower limb look for synergists.
Now in knee standing for extension
everyone is taught the quadriceps and hamstrings
where is the synergist. The only muscle that can come close is the gastrocnemius.
Do you have another muscle in mind?
Have you ever spoken to a patient that had their knee either replaced or reconstructed and told you that when they were standing the knee felt loose or not strong or not secure?
When you do just ask them what mkusclwes were rehabilitated and they will tell you the quads and hammies and nothing else. Once a programme concentrating on the gastroc, followed by the hammies and nothing else their function/abnormal sensation disappears.

I'll leave it up to you.
Regards
Paul C
musmed
Quote:
Originally Posted by m weber View Post
Paul I will go over this as I see it and everything I ve read indicates.

Muscle can only contract they can not lengthen by themselves, they can lengthen thru movement of bone, joints this can be acheived thru direct muscle contraction of angnositic muscle or movement of the body above it.

so muscle can contract cause direct movement or eccentric contract to slow movement.

If looking at using a simple example of the knee any muscle which is anterior to the knee joint axis and crosses that joint when contracting will cause a extension moment at the knee joint, whether the movement of extension occurs is a completly different thing and depends on many factors.

The same can be said for muscle that cross the knee joint and are posterior to the knee joint axis, They will cause a flexion moment at the knee joint when they contract. Ie the hamstrings and Gastroc are these muscles.

Now as I have stated these muscle will also go thru eccentric contraction to help stabile the joint slow motion in this case knee extension. But and this is the big BUT just because the muscle is working it does not mean that it is causing the motion. It is slowing the movement.

Muscles can not push the Gastroc is posterior to the knee joint axis it can not cause an extension moment to occur at the knee joint.
Quote:
Originally Posted by musmed View Post
Dear Sir
I beg to differ.

From 81 odd degrees to 90 full knee extension. This is produced by the gastroc muscle.

Just for one moment, look at the ischial tubersoity and the hams (origin to insertion).
Now turn it upside down, do they not look lie the gastroc and calcaneus.

If you do not beleive me, give the great Professor Nicoli Bogduk an email at the bone and joint institute at the Newcastle Hospital NSW australia. If I cannot put you straight he will.

Bye
www.musmed.com.au

I never look inside the box, only outside of the box (this is the hard part). Those who do only look inside the box see what the rest have seen, basicaly nothing.
Quote:
Originally Posted by m weber View Post
I guess it goodbye then, but if you read this it does not matter what you or I think where is the evidence in a journal of peer review. I´m sure Professor Nicoli Bogduk must have produced one. Until then Gastroc contraction produces a plantarflexion moment at the talocural joint and a flexion moment at the Knee .
Quote:
Originally Posted by musmed View Post
Buddy Holly was right.
Dumb dee dumb dumb, Oh Boy.

Just sit on a chair, place your fingers around your gastrocnemius muscle and stand up.
Notice anything?
Yes the gastroc contracted, there was no plantar flexion in this motion.
Please explain, just use your observation, not a peer review journal. Simple it not.

Do you not think that over many millions of years, the foot was designed to:
get away from danger (and not get eaten) catching food and breeding?
So when you look at what muscles and joints of the lower limb do, think about what I have just written.
It is absolutely pointless to be able to plantar flex the foot if you cannot stand up prior to this motion.
Have a gentle think about it. This is what looking outside the box is all about.

Regards
Pauy Conneely.
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Old 13th February 2010, 08:37 AM
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Default Re: Effect of Gastrocnemius at the knee joint

Quote:
Originally Posted by musmed
Buddy Holly was right.
Dumb dee dumb dumb, Oh Boy.

Just sit on a chair, place your fingers around your gastrocnemius muscle and stand up.
Notice anything?
Yes the gastroc contracted, there was no plantar flexion in this motion.
Please explain, just use your observation, not a peer review journal. Simple it not.

Do you not think that over many millions of years, the foot was designed to:
get away from danger (and not get eaten) catching food and breeding?
So when you look at what muscles and joints of the lower limb do, think about what I have just written.
It is absolutely pointless to be able to plantar flex the foot if you cannot stand up prior to this motion.
Have a gentle think about it. This is what looking outside the box is all about.

Regards
Pauy Conneely.
Ok Paul I´m not sure you needto call me Dumb over the internet but ok lets try and keep this on a professional level.

I will call you on you knowledge of mechanics of the knee in relation to the Gastroc.

I will attach some basic pictures for you of the action of a muscle namly the Gastroc. I beleive that you are getting confused on this point.

Just because a knee joint is going thru a motion of extension it does not mean that the Gastroc is causing that motion, it maybe under a state of work eccentrically contracting to stabilize the knee to stop hyper extension. This would still mean that Gastroc is causing an internal knee joint flexion moment.
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Old 13th February 2010, 08:39 AM
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Default Re: Effect of Gastrocnemius at the knee joint

Here is one picture for you...
Attached Images
File Type: jpg knee extension moment 1.jpg (10.9 KB, 182 views)
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Old 13th February 2010, 08:40 AM
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Default Re: Effect of Gastrocnemius at the knee joint

and another.....
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Old 13th February 2010, 08:42 AM
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Default Re: Effect of Gastrocnemius at the knee joint

Now the above 2 very basic picture show the action of the muscle when it contracts. I just included the Quads to show a knee extension moment caused by a muscle.
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Old 13th February 2010, 08:59 AM
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Default Re: Effect of Gastrocnemius at the knee joint

heres some reading for you

Taken from and old text book- Gait analysis an indroduction Michael Whittle pages 62-63 3rd edition.

Quote:
MIDSTANCE - ankle and foot The midstance rocker also called the 2nd rocker or ankle rocker, occurs during midstance and terminal stance. It is characterized by forward roatation of the tibia about the ankle joint as the foot remains flat on the floor, the ankle angle changing from plantarflexion to dorsiflexion, with the triceps surea contracting eccentically.

.. bits cut out which are not relevent.....
The ground reaction force vector moves forward along the foot from the time of foot flat onwards , moving into the forefoot prior to heel raise.

Moments and powers- knee At the knee the force vector remains behind the joint producing an external flexor moment, opposed by an internal extensor moment due to quadirceps contraction

... bits cut out not relevent....

as the knee motion changes from flexion to extension power generation takes place. The ankle shows an increased internal plantarflexion moment throughout mid-stance and into terminal stance as the force vector moves onto the forefoot. This moment is generated by the triceps surea contracting eccentrically and absorbing power.
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Old 13th February 2010, 09:18 AM
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Default Re: Effect of Gastrocnemius at the knee joint

Right next...

Quote:
HEEL RISE knee . The knee has extension peak close to the time of heel rise. Around this time active plantarflexion brings the ground reaction force forward, moving on to the forefoot and in front of the knee joint. This attempts to extend the knee, an effect known as the plantarflexion/knee extension couple. Contraction of the gastroc augments the action of the soleus as far as the ankle joint is concerned, but it acts as a flexor at the knee, preventing hyperextension and subsequently initiating knee flexion.
Quote:
moments and powers bits cut out not relevent...

At the knee quadriceps contraction has ceased prior to heel rise, and the internal knee moment has reversed to become flexor. According to perry this occurs because the upper body moves forward faster than the tibia. . If the ankle joint was totally free, the forward motion of the body would simply dorsiflex the ankle. However the contraction of the triceps surea slows down the forward motion of the tibia, so that as the femur moves forward an external extension moment is generated at the knee, opposed by an internal flexor moment.
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Old 13th February 2010, 09:27 AM
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Default Re: Effect of Gastrocnemius at the knee joint

Paul thats the type of stuff you I beleive should be teaching the groups you instruct on FMT, but it does take some understanding of internal and external moments.

I think in this way. Gastroc contraction will cause an internal talocural plantarflexion moment......... which will lead to an increase in Ground reaction force which will lead to an increased external talocural dorsiflexion moment.

So if you have evidence of another action of the Gastroc please provide it
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Old 13th February 2010, 11:24 AM
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Default Re: Effect of Gastrocnemius at the knee joint

If you look in any text on knee extension it is 10 degrees and the quadriceps perform this function. Paul do you have a citation where Janda claims there is a muscle other than the quads that provides extension of the leg at the knee? The gastroc is a primary knee flexor.

Contraction of the posterior muscles of the leg and thigh are antagonists to the quads and provide a stabilizing counter-force to the powerful quads, they do not initiate primary knee extension.
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Old 13th February 2010, 12:14 PM
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Default Re: Effect of Gastrocnemius at the knee joint

Michael and David:

There is no question that gastrocnemius contractile activity produces an internal knee joint flexion moment. If, however, we consider that the gastrocnemius contractile activity can also cause a shift in the ground reaction force (GRF) vector more anteriorly on the plantar foot so that it now is directed anterior to the horizontal knee joint axis, then indeed it could be said that the gastrocnemius may also create an external knee joint extension moment. However, most of the forward dynamics research I have read seems to suggest that, overall, the gastrocnemius causes a net knee joint flexion moment whereas the soleus causes a net knee joint extension moment.

All in all, until medical professionals and biomechanics all make it very clear in their discusssions, papers and lectures whether muscle activity is causing either internal moments or external moments or both types of moments about a given joint, then we will continue to be swimming in murky waters regarding the function of muscles of the foot and lower extremity during weightbearing activities.
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Old 14th February 2010, 04:19 PM
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Default Re: Effect of Gastrocnemius at the knee joint

i dont think Mr. C is contradicting you M Weber:

he is simply stating that the gastroc functions better when the knee is extending i.e. when you have already stood up. tension is placed on gastroc and a resultant plantarflexion moment is possible.
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Old 15th February 2010, 01:02 AM
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Default Re: Effect of Gastrocnemius at the knee joint

Quote:
Originally Posted by Peter1234 View Post
i dont think Mr. C is contradicting you M Weber:

he is simply stating that the gastroc functions better when the knee is extending i.e. when you have already stood up. tension is placed on gastroc and a resultant plantarflexion moment is possible.
Peter Here is a quote from the man himself.

Quote:
I hate to tell you this, but the gastroc is the strrongest knee extensor (just sit for any USA sports medicine exam)
and there are another 17 beleivers in the UK.
Sounds like he is saying the Gastroc is a knee extensor infact the strongest......

Contraction of the Gastroc does not cause an internal extensor moment at the knee but will cause an internal flexion moment at the knee...
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Old 15th February 2010, 12:15 PM
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Default Re: Effect of Gastrocnemius at the knee joint

Michael

I think I see what Paul may be saying is this: (I might also be completely wrong in my deduction)

The Gastroc plantarflexes the ankle and so therefore produces a GRF at the forefoot. The force vector projection of the GRF causes an extension moment of the knee and therefore the gastroc is an indirect extensor of the knee.

This is more easily visualised in a knee that hyperextends, on a subject with this problem we often see the knee hyperextend as the GRF moves to the forefoot. This would not be possible if the Gastroc soleus complex was not able to plantarflex the ankle.

I'm not sure tho that it is useful to label the GSC as a knee extensor tho since this concept relies on the GRF vector projection relative to the knee joint. This vector projection can be extremely variable depending on the action of interest.

Regards Dave
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Old 15th February 2010, 12:56 PM
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Default Re: Effect of Gastrocnemius at the knee joint

Quote:
Originally Posted by David Smith View Post
Michael

I think I see what Paul may be saying is this: (I might also be completely wrong in my deduction)

The Gastroc plantarflexes the ankle and so therefore produces a GRF at the forefoot. The force vector projection of the GRF causes an extension moment of the knee and therefore the gastroc is an indirect extensor of the knee.

This is more easily visualised in a knee that hyperextends, on a subject with this problem we often see the knee hyperextend as the GRF moves to the forefoot. This would not be possible if the Gastroc soleus complex was not able to plantarflex the ankle.

I'm not sure tho that it is useful to label the GSC as a knee extensor tho since this concept relies on the GRF vector projection relative to the knee joint. This vector projection can be extremely variable depending on the action of interest.

Regards Dave
Hi Dave

While I agree that the FF GRF vector may cause an external extension moment at the knee ( I guess there are a few variable to consider here as well) and that Plantarflexion will add to the force of this Vector along with many other things, I would label this as a secondary action of the muscle and direction action would be an internal plantarflexion moment at the Talocural and internal flexion moment at the knee.

but Paul language had none of these type of statements, but statments such as this
Quote:
I hate to tell you this, but the gastroc is the strrongest knee extensor (just sit for any USA sports medicine exam)
and there are another 17 beleivers in the UK.
which does not read the same to me and when I challenged this statement I got called Dumb in a round about way so thought I had better clear the air so to speak.
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Old 15th February 2010, 01:17 PM
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Default Re: Effect of Gastrocnemius at the knee joint

Michael quoted me from another post and added.
Quote:
and Eric Fuller


Note when using achillies tendon I also include the muscles gastroc and soleus and their action of contraction and excentic contraction

Now as stated the pull of the achillies tendon can cause 3 different motions at the STJ, if the STJ is medially deviated the motion around the STJ axis will most likely be an external pronation moment. Now the the insertion point is lateral to the STJ axis the load on the achillies tendon will be less, it has a mechanical advantage. ie the natural motion of the foot is pronation the achillies is at a mechanical advantage.

So if we use a medial skive device as part of our treatment plan we maybe adding to the load of the achillies tendon.

As the medial skive will cause an external STJ supination moment the axis will also deviate laterally, which may mean either a shorter level arm or the insertion point of the achillies will be medial to the STJ axis which would then mean the muscle must help "control" the natural motion of pronation of this patient and the type of work will change and if the load placed on it by the body is too much an increase in symptoms.
I'd like to clarify the statement that was quoted. Tension in the Achilles tendon will tend to cause an ankle plantar flexion moment and shift the center of pressure under the foot anteriorly. As the center of pressure shifts anteriorly this may change the moment from ground reaction force. With a medially positioned STJ axis this shift in location of ground reaction force will cause an increase in pronation moment from the ground. With a laterally positioned axis the center of pressure will stay close the projection of the STJ axis and there will be little change in the moment from ground reaction force and the tension in the Achilles tendon will cause a direct supination moment and looking at only the interaction of Ground reaction force and Achilles tesnion at the STJ, there would be a net increase in supination moment at the STJ. However, other muscles (peroneals) could change the net moment at the STJ.

In regards to wedging of the rearfoot and load in the Achilles tendon.

The Load in the Achilles in gait will probably determined by the activation of the muscles attached to the tendon. The more the activation the greater the load.

On average, he Achilles has a lever arm of over 2cm at the ankle joint and probably less than 0.5 cm at the STJ. Therefore, for a given amount of force, there will be much greater moments at the ankle joint with tension in the tendon. I've done cadaver work attempting to measure tendon excursion with joint motion to assess lever arm of tendons. The tendon moves a lot more with ankle motion and hardly at all with STJ motion.

The resistance to the force from the achilles tendon comes from ground reaction force. The further distal the force is on the foot the higher the resistance to ankle joint plantar flexion. So, a rocker bottom shoe that has the center of pressure at the rocker point will decrease the lever arm of ground reaction force about the ankle joint and ankle joint plantar flexion will occur with less tension in the tendon. Again the resistance to moments from the AChilles tendon will have much longer lever arms about ankle joint. Therefore, it is unllikely that shifting the COP with varus or valgus wedges will have very little effect on the load of the Achilles tendon.

Regarding the shifting of the position of the STJ axis with motion of the STJ. The amount of shift in the location of the axis is proportion to the amount of motion of the joint. Wedging under the heel will rarely cause a change in joint position of more than a couple of degrees. Therefore, I maintain the changes in moments about the STJ axis caused by axis shift will be minimal.

Cheers,

Eric
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Old 15th February 2010, 02:34 PM
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Default Re: Effect of Gastrocnemius at the knee joint

'I hate to tell you this, but the gastroc is the strrongest knee extensor (just sit for any USA sports medicine exam)
and there are another 17 beleivers in the UK.'

Sounds like he was having a bit of fun with you

Peter
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Old 15th February 2010, 02:50 PM
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Default Re: Effect of Gastrocnemius at the knee joint

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'I hate to tell you this, but the gastroc is the strrongest knee extensor (just sit for any USA sports medicine exam)
and there are another 17 beleivers in the UK.'

Sounds like he was having a bit of fun with you

Peter
So your going on record to say that the above statment is wrong ?

As for having a bit of fun not a chance. It would have been better if he was.
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Old 15th February 2010, 04:01 PM
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Default Re: Effect of Gastrocnemius at the knee joint

happy days
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Old 19th February 2010, 02:02 AM
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Default Re: Effect of Gastrocnemius at the knee joint

OK I learned a lot seeing this from the podiatry view from the ground up. But my view is from the head down. When a client has a forward head posture the weight is on the fore foot and it pushes the knees int hyper extension. The origin of the gastroc is then posterior of the insertion and it fails in flexion potential.
Therefore I find trigger points in the soleus and planter surface muscles. The gastrocnemius may be diminished due to lack of loading with the knee flexed or it may have trigger points unilaterally from rotational stabilization.
When I suffered from this as a teen in the 1950's there was a fad of earth shoes which had elevated toes and no heel. This flexed my knees and helped me through the problem.
The podiatrist that refers to me said I need you because I am only trained op to the knee and many times you have to look much higher for the cause of the problem.
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Old 19th February 2010, 12:25 PM
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Default Re: Effect of Gastrocnemius at the knee joint

I would be interested in reading any papers that show how the GSC is an extensor of the knee. I can't find much, I have attached one that discusses this but is not all that robust in its definitions so its a bit hard to say exactly what they mean. However it seems to be saying that the GSC is an extensor in some cases due to the GRF vector it causes. I believe this is not a useful idea since you could say almost any muscle has any action based on the GRF vector at the time and location of interest. I.E. the gluteus maximus is an extensor of the knee or the deltoids extend the knee when the arms are extended and cause the CoP to move forward on the plantar foot.

Regards Dave
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Old 19th February 2010, 01:09 PM
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Default Re: Effect of Gastrocnemius at the knee joint

or that your biceps are a knee extensor..... Drink alot of beer get a huge beer belly, COP moves forward increase in GRF.... external extension moment at the knee.
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Old 22nd February 2010, 08:13 PM
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Default Re: Effect of Gastrocnemius at the knee joint

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OK I learned a lot seeing this from the podiatry view from the ground up. But my view is from the head down. When a client has a forward head posture the weight is on the fore foot and it pushes the knees int hyper extension.
Yes, if everything else stays in the same place, and you tilt the head forward the center of mass will move forward. However, the location for ground reaction force may move forward to a location under the forefoot if the patient contracts their gastroc soleus muscles. There are other things a person could do to maintain balance when they tilt their head forward. Someone could just choose to lean back a little bit to put their center of mass over the center of their feet.

Cheers,

Eric
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Old 22nd February 2010, 11:18 PM
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Default Re: Effect of Gastrocnemius at the knee joint

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Yes, if everything else stays in the same place, and you tilt the head forward the center of mass will move forward. However, the location for ground reaction force may move forward to a location under the forefoot if the patient contracts their gastroc soleus muscles. There are other things a person could do to maintain balance when they tilt their head forward. Someone could just choose to lean back a little bit to put their center of mass over the center of their feet.

Cheers,

Eric
Yes this is a frequent adaptation. It usually becomes progressive resulting in inward rotation of the arms and shoulders with a reflex pronation of the feet.
The term that has been coined for this is bio-implosion.
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Old 23rd February 2010, 04:44 PM
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Default Re: Effect of Gastrocnemius at the knee joint

hi,

what is 'reflex pronation of the feet?'
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Old 23rd February 2010, 10:04 PM
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Post Re: Effect of Gastrocnemius at the knee joint

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hi,

what is 'reflex pronation of the feet?'
Here is the experiment: Chose a subject with good foot reflexes. Have the subject stand bare foot where you can place a finger or two under the longitudinal arch. Have the subject shift the body over one leg. there will generally be a supination of the weight bearing foot and pronation of the other.

Now to demonstrate the implosion: Have the subject stand with erect posture, hands at sides, thumbs pointing forward. Have the subject rotate the arms so that the thumbs are pointing lateral. There should be a slight supination. Have the subject rotate the arms so that the thumbs point medial and further to posterior. There should be a slight pronation.

Differences left to right may indicate habitual antalgic posture. Lack of reflex may indicate habitual posture guarding.

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Old 23rd February 2010, 11:09 PM
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Default Re: Effect of Gastrocnemius at the knee joint

Quote:
Originally Posted by HansMassage View Post
Yes this is a frequent adaptation. It usually becomes progressive resulting in inward rotation of the arms and shoulders with a reflex pronation of the feet.
The term that has been coined for this is bio-implosion.
Hans Albert Quistorff, LMP
Antalgic Posture Pain Specialist
I thought that bio-implosion was what happens in the bathroom (water closet) the morning after eating chips, bean dip and jalapenos and drinking beer the whole night before.
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Old 24th February 2010, 12:54 PM
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Default Re: Effect of Gastrocnemius at the knee joint

Quote:
Originally Posted by HansMassage View Post
Here is the experiment: Chose a subject with good foot reflexes. Have the subject stand bare foot where you can place a finger or two under the longitudinal arch. Have the subject shift the body over one leg. there will generally be a supination of the weight bearing foot and pronation of the other.

Now to demonstrate the implosion: Have the subject stand with erect posture, hands at sides, thumbs pointing forward. Have the subject rotate the arms so that the thumbs are pointing lateral. There should be a slight supination. Have the subject rotate the arms so that the thumbs point medial and further to posterior. There should be a slight pronation.
You are talking about the supination and pronation of the forearm, right?

Eric
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Old 24th February 2010, 04:55 PM
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Default Re: Effect of Gastrocnemius at the knee joint

Hi Hans,

on slightly different note -

you say on your reflex-posturology website

http://reflexposturology.magnet-therapy-how-why.com/

with regards to stimulation of lymph: 'The goal is to normalize the signals from the low back and legs to your brain and reduce the chronic tension that stresses the nerves and blocks the movement of lymph that removes wast products from the legs that can set off cramps'

have you ever tried this therapy on patients with chronic lymphedema, and if so are there any RCT trials to show for, and if not, why not??

Peter
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Old 25th February 2010, 01:17 AM
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Default Re: Effect of Gastrocnemius at the knee joint

Quote:
Originally Posted by Peter1234 View Post
Hi Hans,

on slightly different note -

you say on your reflex-posturology website

http://reflexposturology.magnet-therapy-how-why.com/

with regards to stimulation of lymph: 'The goal is to normalize the signals from the low back and legs to your brain and reduce the chronic tension that stresses the nerves and blocks the movement of lymph that removes wast products from the legs that can set off cramps'

have you ever tried this therapy on patients with chronic lymphedema, and if so are there any RCT trials to show for, and if not, why not??

Peter
It has worked well on localized areas of lymphedema, also reducing there chronic episodes.
Thank you for searching out and reading my blogs. I am in the process of setting down my findings and communicating with others that I have learned various aspects of the work from. I am trying to organize a trial with local massage students to see if with double blind use of magnetized and non magnetized sphere as a treatment tool there is a difference in time and perception doing trigger point therapy.
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