Transcription
So when you're trying to learn the muscles of the forearm, I really think the order that you're learning the muscles in matters. So I'll show you what I think is the perfect order to learn them in.
So you want to locate the biceps brachii. The biceps brachii points to this V shape here. The big arm of the V is the brachioradialis. The little arm of the V is the pronator teres. So you want to start from the pronator teres and begin with the muscles on the palm side.
On the palm side of your arm, you're mostly going to find wrist flexors and finger flexors. And then obviously, the pronator teres pronates, so rotate your arm so your palm is downward. All right, so we find the pronator teres. Right next to it, this muscle, follow it up. The pattern that we're going to see is the names tell you the action, the body part doing the action, and then they add extra words to differentiate muscles that are doing the same action to the same body part. Part. So you'll see what I mean momentarily.
So this muscle here, because it is on the anterior side of your arm, it is going to be a flexor. It's going to the wrist, so it's flexor carpi. And it's on the thumb side, so they named it the flexor carpi radialis, a wrist flexor on the radial side of your arm. We look next to the flexor carpi radialis, and we see this muscle right here. It is going right to the palm, the palmaris longus. We go next to the palmaris longus, this muscle here. Sometimes people kind of think it's on the back of your arm, but if you follow it up, it's still attached to the anterior side, so it's still going to be a flexor. So on the other side of the palmaris longus, we had the flexor carpi radialis, which would make this the flexor carpi ulnaris.
All right, so we rotate around. Next to the flexor carpi ulnaris, we go to the back. We're going to change one word. On the front, we have our flexors. On the the back, we have our extensors. So next to the flexor carpi ulnaris is the extensor carpi ulnaris. And then we keep going around. Next to that is the extensor digiti minimi. It's called that because, look, it's going right to the pinky, so it extends your littlest digit, extensor digiti minimi. Next to that, this one, follow it up. It is going to all of your fingers. That is why it is the extensor digitorum.
Next to the extensor digitorum, well, well, if this was the extensor carpi ulnaris, this is the extensor carpi radialis, but it has a friend, so it had to add an extra word. This is the extensor carpi radialis brevis, extensor carpi radialis longus. So often times, if you have a brevis, you have a longus because think brief, like short. Brevis is short. Longus is longer. And then if we look next to the extensor carpi radialis longus, we are back to the big arm of the V, which was the brachioradialis.
I have not yet mentioned these two. These are going to the thumb. And I kind of remember these by knowing one is going to be an abductor, the other is going to be an extensor. They're both going to have pollicis for the second word because they both move the thumb. And then one's going to be a brevis, one's going to be a longus. So I look at them and I know that this one is going to be the abductor because it's kind of more to the side of your arm, and abduction is going out to the side. And then this one is the extensor because it's attached a little bit more to the back, and extension is going backwards. And then I know this one is going to be the brevis, this one is going to be the longus. And then I just put that all together to remember that this is the abductor pollicis longus, the extensor pollicis brevis.
All right, so that takes care of the back of the arm. And now we're going to look at the deep muscles on the anterior arm. If we look under the flexor carpi radialis and the palmaris longus, there's this muscle peeking out that is the flexor digitorum superficialis. It is superficial because they're comparing it to another muscle that's even deeper. So we take off these muscles. This is the rest of the flexor digitorum superficialis. Underneath there's two muscles. And I just remember one goes to the fingers, one goes to the thumb. This one's more on the thumb side. Um, so I know this is the one that goes to the fingers. So this was the flexor digitorum superficialis because underneath it is the flexor digitorum profundus. Think like profound. Profound means deep. Um, that is why this is the flexor digitorum profundus. And then next to it, this is the flexor pollicis longus.
If we rotate back around and we take off this group with the brachioradialis, underneath it, we can see now the pronator teres. How it's inserting onto the radius. The fibers going in the opposite direction as the pronator teres, that is the supinator. So that is the antagonist.
All right, so that's all I have to say about muscles of the forearm. I did not mention every single muscle because not everything is relevant to the students that I'm primarily making this video for. So if you have any questions about anything that I didn't mention, please let me know. Have a great day and have fun learning.