Explain the general relationship between the muscles that flex an...

Question

Explain the general relationship between the muscles that flex and extend the wrist, including their location on the body.

Accepted Answer

Hi, everyone. Let's look at our next question. It says which of the following muscles flexes the wrist and inserts into the pisiform bone bone and the base of the fifth metacarpal bone. Choice. A flexor Dior super superficialis B, flexor carpi, ulnaris, C flexor Dior Profundus or D flexor carpi radialis. So the pie is a form bone is that little knobby bone on the outside of the wrist or the pinky side and the base of the fifth metacarpal bone. So between the wrist on the pinky side to the base of the pinky itself and this muscle is choice B the flexor carpi. So it's on the side of the forearm and it comes from the medial epi of the humerus and the and process of the ulna. So that bumpy part of the elbow. So it comes from the elbow area and then inserts into that pisiform bone and the base of the pinky and its motion is that it flexes the wrist and then helps in wrist abduction or bringing the hand towards the midline of the body. So again, that's the flexor carpal neiss and it's that little muscle going from the elbow onto the sort of a pinky side of the wrist and base of the and the palm there. So let's look at why our other answer choices are incorrect. And we've got two really closely related muscles as you can tell by their names. Choice. A the flexor Dior superficialis and c the flexor Dior profundis. So both of these muscles are located in the middle of the forearm. They come from the medial epi condal of the humerus and from the ulna and then attached to the phalanges of the four fingers. So not the thumb and just have a slightly different action. They work together to curve the fingers inwards and extend them again. The flexor superficialis sort of splits and goes around and under the flexor tom profundus and the superficialis comes into the base of the middle phalanges. So when you want to move your whole finger in and out, that's sort of moving that middle phalanges. While the flexor de de Profundis, which then goes through that split in the F DS as you might call it attaches at the base of those distal joints of the phalanges. So it's what helps move, indep, moves the tip of the fingers. So they don't quite move independently, they work together. But the super facialis is most responsible for the base part of the finger movement and the flexor de de Profundis for movement further down the finger. So, so this FDP flexor digital Profundis inserts into the base of the digital distal phalanges, excuse me. But that's why they're not our correct answer. They do help with flexion of the wrist and then of course, movement of the fingers to grasp things and then finally choice d the flexor carpi radialis. This one is on the inner side of the forearm. It originates from the medial epi condal of the Humes and it inserts into the base of the second metacarpal bone. And as a result, it flexes the wrist like our other are other muscles here. And it also aids in wrist abduction. So, moving the hand away from the midline of the body. So when we look at our answer choices, we'll cross this out again. The one that we're looking for is the one that moves from the elbow to the pinky side of the wrist. Whereas our flexor carpi radialis goes down the inner part of the forearm into the second metacarpal bone. So it moves the wrist away from the midline rather than toward the midline. And then the F DS and FDP have to do with curving the fingers inward as well as wrist movement. So once again, the muscle that we're looking for that flexes, the wrist inserts into the pisiform bone and the base of the fifth metacarpal bone is choice B, flexor carpi ulnaris, see you in the next video

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Explain the general relationship between the muscles that flex and extend the wrist, including their location on the body.

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Origin and Insertion practice set