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Name the muscle that attaches to the scapula beginning with the letter O ? Ask your educator or search the web !

Can you name this muscle and its action and attachments ? If you know you can answere this question you must then ask another muscle question = A with a Q
Keep the A+Q chain running ! get that brain working, clues can be action, origin or insertion orientated.

Replies to This Discussion

Permalink Reply by Joseph E. Muscolino on October 12, 2009 at 10:22am

Hmm... Yes, the brachialis is pretty much always listed as the prime mover of elbow joint flexion, but it is most likely due to having a greater physiologic cross section, i.e., having more tissue to have more actin-myosin cross-bridges, thus more pulling power. I am not sure how the biceps brachii crossing the glenohumeral joint would matter UNLESS the GH joint is moved in such as way to change the length-tension relationship of the biceps brachii. But, if that does not happen, I do not see being a two-joint muscle affects its "credibility" / strength.
Joe :)

Nate Ewert said:

Many people think biceps brachii is the prime mover for elbow flexion, but it is not. Because it crosses the elbow and shoulder joints, it loses some of it's credibility. That leaves brachialis.

Millie Jones said:
A: biceps brachii

Q: Where is the insertion of the diaphragm?

Permalink Reply by Joseph E. Muscolino on October 12, 2009 at 10:26am

the diaphragm attaches circumferentially to the lower rib cage 360 degrees around (and L1-L3) and its other "attachment" is considered to be its central tendon. Which one is called the "origin" or "insertion" does not seem that important to me...it has two "attachments," each one can move or stay fixed.

Question: What is the action of the extensor carpi radialis longus at the elbow joint? And why?

Joseph E. Muscolino said:

Hmm... Yes, the brachialis is pretty much always listed as the prime mover of elbow joint flexion, but it is most likely due to having a greater physiologic cross section, i.e., having more tissue to have more actin-myosin cross-bridges, thus more pulling power. I am not sure how the biceps brachii crossing the glenohumeral joint would matter UNLESS the GH joint is moved in such as way to change the length-tension relationship of the biceps brachii. But, if that does not happen, I do not see being a two-joint muscle affects its "credibility" / strength.
Joe :)

Nate Ewert said:
Many people think biceps brachii is the prime mover for elbow flexion, but it is not. Because it crosses the elbow and shoulder joints, it loses some of it's credibility. That leaves brachialis.

Millie Jones said:
A: biceps brachii

Q: Where is the insertion of the diaphragm?

Permalink Reply by Nate Ewert on October 12, 2009 at 1:03pm

I think you are very correct. The two joint issue is an easy way to look at it, at first. The hamstrings cross two joints but are still considered agonists for knee flexion.They don't call them bicep curls for nothing! "Credibility" was probably not the best term to use.

Joseph E. Muscolino said:

Hmm... Yes, the brachialis is pretty much always listed as the prime mover of elbow joint flexion, but it is most likely due to having a greater physiologic cross section, i.e., having more tissue to have more actin-myosin cross-bridges, thus more pulling power. I am not sure how the biceps brachii crossing the glenohumeral joint would matter UNLESS the GH joint is moved in such as way to change the length-tension relationship of the biceps brachii. But, if that does not happen, I do not see being a two-joint muscle affects its "credibility" / strength.
Joe :)

Nate Ewert said:
Many people think biceps brachii is the prime mover for elbow flexion, but it is not. Because it crosses the elbow and shoulder joints, it loses some of it's credibility. That leaves brachialis.

Millie Jones said:
A: biceps brachii

Q: Where is the insertion of the diaphragm?

Permalink Reply by Stephen Jeffrey on October 12, 2009 at 3:09pm

Josephs Question is

What is the action of the extensor carpi radialis longus at the elbow joint? And why?

Permalink Reply by Trevor Chisman on October 12, 2009 at 4:20pm

The ECRL flexes the forearm at the elbow.

Why? That I'm going to have to put my hands up and say I'm not sure.

So next question is left for the person who can answer the Why?

Stephen Jeffrey said:

Josephs Question is What is the action of the extensor carpi radialis longus at the elbow joint? And why?

Permalink Reply by Millie Jones on October 13, 2009 at 5:27pm

This is funny. I went back and forth with these two. As a matter of fact I deleted my answer at first and went to my A&P textbook. I looked up agonist to be sure I was understanding the question and the book said: "For example, the biceps brachii is the prime mover for the flexion of the forearm."

The Massage Connection Anatomy & Physiology (second edition) Kalyani Premkumar
Lippincott Williams & Wilkins publishing

So now I AM confused. I will do some more research.

Thanks!
Millie

Permalink Reply by Jeff Sims on October 13, 2009 at 8:01pm

why does ECRL flex the forearm at the elbow?

because it can? extensor carpi radialis longus (ECRL) crosses the elbow joint, so like many forearm muscles that act mainly on the hand at the wrist, it has the potential for action at the elbow. its action at the elbow is flexion (albeit weak) because it crosses the elbow anteriorly.

to better understand this, consider brachioradialis, a more obvious flexor of the forearm at the elbow, with attachments slightly more proximal than ECRL (notice how brachioradialis' strength depends upon the position of the forearm at the radioulnar joint). according the Travell, the action of ECRL is "chiefly radial deviation of the hand."

next question?
what muscle is an atagonist of the diaphragm with attachments that include inguinal ligament, crest of the ilium, thoracolumbar fascia and cartilages of the last six ribs (interdigitating with fibers of the diaphragm)?

Trevor Chisman said:

The ECRL flexes the forearm at the elbow.

Why? That I'm going to have to put my hands up and say I'm not sure.

So next question is left for the person who can answer the Why?

Stephen Jeffrey said:
Josephs Question is What is the action of the extensor carpi radialis longus at the elbow joint? And why?

Permalink Reply by Nate Ewert on October 14, 2009 at 8:49am

Transverse abdominus. That one threw me off with being an antagonist to the diaphragm. Itmakes sense now though.

What three muscles have insertions on the mandile and close the jaw?

Permalink Reply by Vicki Walther on October 14, 2009 at 3:31pm

The three muscles that insert on the mandible and close the jaw are the muscles of masication:
temporalis, masseter and the medial pterygoid

Next question:
this muscle when chronically tight causes an ipsilateral shift in the pelvis and may present as a functional short lower extremity.

Permalink Reply by Jeff Sims on October 15, 2009 at 5:18am

Dr. Muscolino:

could you please explain if and how someone might control the contraction of one end (or both ends) of the diaphragm? i've studied and practice pranayama and other breathing techniques, but this aspect of respiration is one that i had not yet considered. how exciting!

thank you for teaching us the truth about attachments. i have enjoyed teaching many students your approach on attachments and the true meaning of origin & insertion.

at your feet,

jaya jeff

Joseph E. Muscolino said:

the diaphragm attaches circumferentially to the lower rib cage 360 degrees around (and L1-L3) and its other "attachment" is considered to be its central tendon. Which one is called the "origin" or "insertion" does not seem that important to me...it has two "attachments," each one can move or stay fixed.

Question: What is the action of the extensor carpi radialis longus at the elbow joint? And why?

Joseph E. Muscolino said:
Hmm... Yes, the brachialis is pretty much always listed as the prime mover of elbow joint flexion, but it is most likely due to having a greater physiologic cross section, i.e., having more tissue to have more actin-myosin cross-bridges, thus more pulling power. I am not sure how the biceps brachii crossing the glenohumeral joint would matter UNLESS the GH joint is moved in such as way to change the length-tension relationship of the biceps brachii. But, if that does not happen, I do not see being a two-joint muscle affects its "credibility" / strength.
Joe :)

Nate Ewert said:
Many people think biceps brachii is the prime mover for elbow flexion, but it is not. Because it crosses the elbow and shoulder joints, it loses some of it's credibility. That leaves brachialis.

Millie Jones said:
A: biceps brachii

Q: Where is the insertion of the diaphragm?

Permalink Reply by Jeff Sims on October 15, 2009 at 5:37am

in the interest of kinesiological precision, may i suggest that teres major is a synergist of latissimus dorsi for actions of the arm at the shoulder (vs. "complete" synergist)? i'm just sayin'...

Millie Jones said:

Stephen Jeffrey said:
Hi Katelyn I think its piriformis.

Of the adductor muscle group, which is the only 2 joint muscle ?

A: Gracilis

Q: Which muscle is sometimes called "the lat's little helper" because it is a complete synergist with the latissimus dorsi?

Permalink Reply by Joseph E. Muscolino on October 15, 2009 at 5:55am

Hmm..., what do you mean by ipsilateral shift of the pelvis? do you mean depressing (ipsilateral tilting) the pelvis, like the entire abductor of the thigh at the hip joint group (e.g., gluteus medius, TFL)? Their "reverse action" is to depress the pelvis at the hip joint, making the iliac crest appear lower, hence being called a short limb...

Vicki Stoddart Walther said:

The three muscles that insert on the mandible and close the jaw are the muscles of masication:
temporalis, masseter and the medial pterygoid

Next question:
this muscle when chronically tight causes an ipsilateral shift in the pelvis and may present as a functional short lower extremity.