Mike wrote-: "The point is that some "forearm" muscles are able to flex the forearm and some forearm muscles are able to extend the forearm. Those are the muscles that cross the elbow joint."
Mike is correct and I applaud his questioning comments. I shouldn't have been so didactic by making a general overarching statement about forearm muscles that is only generally true, but not absolutely true. I therefore need to qualify my statements with a more detailed explanation, which is always a good thing, because it promotes a better (more accurate) understanding.
Theoretically, it can be said that any foreram muscle that has its origin (or part of its origin) above the elbow joint can assist in flexion or extension of the elbow joint depending on its position and muscle bulk - even though that forearm muscle may have another primary function (moving more distal joints).
I have therefore produced two photos.
The photos are too large to embed in this message, so I will provide links.
Take for example the aconeus muscle. It has its origin above the elbow joint and its insertion below the elbow joint. In that sense, it can be perceived to be an elbow extensor muscle. However, it is a comparatively tiny muscle relative to the triceps muscle and plays very little role in active elbow extension.
The same applies to the brachioradialis muscle. It has its origin above the elbow joint and its insertion near the wrist. It can definitely flex the elbow joint, but considering its relatively small bulk (compared to the biceps and brachialis muscles) and its far insertion point (which decreases leverage) it plays a far smaller role in elbow flexion that the upper arm muscles (biceps and brachialis muscles) which have great leverage because of their proximal forearm insertion points. Its main role is to produce a neutral forearm position when the forearm is extended in a non-neutral position (either supination or pronation) and the forearm is then flexed to a neutral position. It helps in rotating the forearm to a neutral position while assisting the biceps muscle in flexing the elbow.
Yodas Luke suggested that extensor digitorum and extensor carpi ulnaris may assist in elbow extension. I don't think that's correct and the photos show why I disagree - note that the extensor carpi ulnaris and extensor digitorum muscles actually arise from an origin below the elbow joint and its only their common extensor tendon that is attached to the humerus just above the elbow joint (at the lateral humeral epicondyle). They have very little leverage in extending the elbow joint - compared to the triceps muscle.
The extensor muscle that has its origin above the elbow joint is the long head of extensor carpi radialis, but its position and small bulk suggests that it has little role to play in elbow extension.
Look at the sheer size of the triceps muscle and the triceps tendon, and consider its advantageous point of insertion. You can then see why its the dominant muscle in elbow extension.
Mike wrote-: "The point is that some "forearm" muscles are able to flex the forearm and some forearm muscles are able to extend the forearm. Those are the muscles that cross the elbow joint."
Mike is correct and I applaud his questioning comments. I shouldn't have been so didactic by making a general overarching statement about forearm muscles that is only generally true, but not absolutely true. I therefore need to qualify my statements with a more detailed explanation, which is always a good thing, because it promotes a better (more accurate) understanding.
Theoretically, it can be said that any foreram muscle that has its origin (or part of its origin) above the elbow joint can assist in flexion or extension of the elbow joint depending on its position and muscle bulk - even though that forearm muscle may have another primary function (moving more distal joints).
I have therefore produced two photos.
The photos are too large to embed in this message, so I will provide links.
Take for example the aconeus muscle. It has its origin above the elbow joint and its insertion below the elbow joint. In that sense, it can be perceived to be an elbow extensor muscle. However, it is a comparatively tiny muscle relative to the triceps muscle and plays very little role in active elbow extension.
The same applies to the brachioradialis muscle. It has its origin above the elbow joint and its insertion near the wrist. It can definitely flex the elbow joint, but considering its relatively small bulk (compared to the biceps and brachialis muscles) and its far insertion point (which decreases leverage) it plays a far smaller role in elbow flexion that the upper arm muscles (biceps and brachialis muscles) which have great leverage because of their proximal forearm insertion points. Its main role is to produce a neutral forearm position when the forearm is extended in a non-neutral position (either supination or pronation) and the forearm is then flexed to a neutral position. It helps in rotating the forearm to a neutral position while assisting the biceps muscle in flexing the elbow.
Yodas Luke suggested that extensor digitorum and extensor carpi ulnaris may assist in elbow extension. I don't think that's correct and the photos show why I disagree - note that the extensor carpi ulnaris and extensor digitorum muscles actually arise from an origin below the elbow joint and its only their common extensor tendon that is attached to the humerus just above the elbow joint (at the lateral humeral epicondyle). They have very little leverage in extending the elbow joint - compared to the triceps muscle.
The extensor muscle that has its origin above the elbow joint is the long head of extensor carpi radialis, but its position and small bulk suggests that it has little role to play in elbow extension.
Look at the sheer size of the triceps muscle and the triceps tendon, and consider its advantageous point of insertion. You can then see why its the dominant muscle in elbow extension.
Jeff.
Well said Jeff- No problem from here. Although I kind of liked it when you finished with "If anyone disagrees with my opinion please comment"
__________________
Life Goal- Developing a new theory of movement based on Brain Science
Interests - Dabbling with insanity
Hobbies- Creating Quality
Please take the following with the largest grain of salt that you can find, as I am not the expert in this department.
It's my understanding that the brachioradialis aids only in flexion, not extension.
There are two muscles, the extensor digitorum and the extensor carpi ulnaris, that aid in the extending of the elbow. The extension of the elbow by these two muscles appears only to come after extension of the fingers and/or the wrist. At best, I think these muscles are subordinate to the actions of the triceps brachii and the anconeus.
Discounting the roles of the triceps brachii and the anconeus in the extending of the elbow requires intoxication.
Ted,
I was only addressing the middle portion of Jeff's post: "Forerarm muscles can only perform the following anatomical actions-:
1) Flex, extend, abduct or adduct the fingers and thumb.
2) Palmarflex or dorsiflex the wrist.
3) Radially deviate or ulnarly deviate the wrist.
4) Pronate or supinate the hand.
Forearm muscles cannot flex or extend the elbow joint because they are distal (peripheral) to the elbow joint.
Jeff."
Hopefully, that makes my post more relevant. The point is that some "forearm" muscles are able to flex the forearm and some forearm muscles are able to extend the forearm. Those are the muscles that cross the elbow joint. I wasn't posting to the degree of relevance or Bucket's drinking habits, all I was pointing out since Jeff asked was that his limited definition was not correct. Not all forearm muscles have tendon attachments that are distal to the elbow joint, as you correctly pointed out in your post with the addition of some extensor forearm muscles.
__________________
Life Goal- Developing a new theory of movement based on Brain Science
Interests - Dabbling with insanity
Hobbies- Creating Quality
Please don't start with the knee bone connected to the thigh bone song.
__________________ Hitting the Ball is the easiest part of the game-hitting it effectively is the most difficult. Why trust instinct when there is a science."1-G.
Ted,
I was only addressing the middle portion of Jeff's post: "Forerarm muscles can only perform the following anatomical actions-:
1) Flex, extend, abduct or adduct the fingers and thumb.
2) Palmarflex or dorsiflex the wrist.
3) Radially deviate or ulnarly deviate the wrist.
4) Pronate or supinate the hand.
Forearm muscles cannot flex or extend the elbow joint because they are distal (peripheral) to the elbow joint.
Jeff."
Hopefully, that makes my post more relevant.
Mike,
Then tell us why would Homer write...."and the Right Forearm is ALWAYS DRIVING." And why would Tomasello say "DRIVE that right forearm to a long right arm" while demonstrating the swinging procedure.
Then tell us why would Homer write...."and the Right Forearm is ALWAYS DRIVING." And why would Tomasello say "DRIVE that right forearm to a long right arm" while demonstrating the swinging procedure.
DG
Dave,
I'm not interested in getting involved in this debate, discussion - I was only commenting on a very narrow topic area within one of Jeff's post- with no intent to have it reflect on any wider issue- pro or con.
If we were to interpret my post- if anything - I would think it would lean more in the direction of supporting your "apparent" viewpoint than it would the "oppositions" - so I am perplexed at the nature of your question to me.
Part of the problem that I see with this thread or posts to this thread is one of communication. Specifically, when you are describing movement let's assume you need to define 1) What the intent is, 2) What muscles are being used, 3) What sensations you are sensing while the movement is being made, 4) What it looks like through the video camera, 5) Where your focus or awareness is while making the movement, 6) etc. - these are all very different for the same movement.
For example, If I decide to Drive my hand/fist through Buckets skull- that doesn't mean that I'm using the fist muscles to do it- that just describes my intent. The muscles that create that motion of the hand might simply be the tricep muscle but of course that would not cause much damage so I'd probably use muscles throughout my body - some for movement, some for support of movement, etc. etc. On to what sensation I might be aware of while I was making the movement - Would that be my hand? no, you'd have greater sensations other places (Bucket can elaborate on this further). Would I individually feel every single muscle that is contracting-No, although they are.
In summary, it's important to understand the context in which you are looking at the movement. For example, in case someone were to read your question and assume that both your quotes were saying the same thing- certainly they are not in this regard : The Homer quote is saying that the Forearm is always driving - that's more of a third party observer comment - as if we were measuring the acceleration rate of the forearm and the Tomasello quote is more from the 1st perspective - the mover- the intent of the mover to drive the forearm or move the forearm. I only use that example to point out the different contexts that one needs to observe- it in no way is meant to separate out one as right and one as wrong.
If one were to want to make some progress or learn during a debate- one might ask questions to clearly understand the opposing view and one might want to clearly define their view for the opposing party. That way you create a platform for agreement to move forward. Hope that helps in some way.
For some reason I feel much better after posting this post- hmm... the only thing I could possibly feel better about would be if Bucket came over to play some cards- Bucket- where are you? Come on over - let's play a friendly game of cards- I've got those candy bars you like! I've got to go now - my Doctor Augusta Golf says I shouldn't be out this long without more medication.
__________________
Life Goal- Developing a new theory of movement based on Brain Science
Interests - Dabbling with insanity
Hobbies- Creating Quality
Dave,
I'm not interested in getting involved in this debate, discussion - I was only commenting on a very narrow topic area within one of Jeff's post- with no intent to have it reflect on any wider issue- pro or con.
If we were to interpret my post- if anything - I would think it would lean more in the direction of supporting your "apparent" viewpoint than it would the "oppositions" - so I am perplexed at the nature of your question to me.
Part of the problem that I see with this thread or posts to this thread is one of communication. Specifically, when you are describing movement let's assume you need to define 1) What the intent is, 2) What muscles are being used, 3) What sensations you are sensing while the movement is being made, 4) What it looks like through the video camera, 5) Where your focus or awareness is while making the movement, 6) etc. - these are all very different for the same movement.
For example, If I decide to Drive my hand/fist through Buckets skull- that doesn't mean that I'm using the fist muscles to do it- that just describes my intent. The muscles that create that motion of the hand might simply be the tricep muscle but of course that would not cause much damage so I'd probably use muscles throughout my body - some for movement, some for support of movement, etc. etc. On to what sensation I might be aware of while I was making the movement - Would that be my hand? no, you'd have greater sensations other places (Bucket can elaborate on this further). Would I individually feel every single muscle that is contracting-No, although they are.
In summary, it's important to understand the context in which you are looking at the movement. For example, in case someone were to read your question and assume that both your quotes were saying the same thing- certainly they are not in this regard : The Homer quote is saying that the Forearm is always driving - that's more of a third party observer comment - as if we were measuring the acceleration rate of the forearm and the Tomasello quote is more from the 1st perspective - the mover- the intent of the mover to drive the forearm or move the forearm. I only use that example to point out the different contexts that one needs to observe- it in no way is meant to separate out one as right and one as wrong.
If one were to want to make some progress or learn during a debate- one might ask questions to clearly understand the opposing view and one might want to clearly define their view for the opposing party. That way you create a platform for agreement to move forward. Hope that helps in some way.
For some reason I feel much better after posting this post- hmm... the only thing I could possibly feel better about would be if Bucket came over to play some cards- Bucket- where are you? Come on over - let's play a friendly game of cards- I've got those candy bars you like! I've got to go now - my Doctor Augusta Golf says I shouldn't be out this long without more medication.
Dude . . . . I got your medicine . . . after reading your last 3 posts . . . . drewitgolf has asked me to feed him the whole bottle . . . . open the hatch suferboy . .. .here comes a big tasty wave . . . . wipe out soon to follow . . .
We better get one of them forum sherrif types over here soon before they start dropping like flies. Yo Belle Starr can you please ban Mikey from posting in this forum . . . LBG may have some liability issues.
B. J. Hathaway, G.S.E.B., M.C.I.
Hybrid Mode
