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Wrist, MR anatomy, palmar, ventral, or anterior,

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focusing on the tendons, nerves, and vessels

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in the palmar aspect of the proximal wrist.

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We're at the distal radial ulnar joint, and a lot

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of black, hypo intense round structures are visible.

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Let's select out the important ones first,

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and the ones that are more generic next.

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I begin with an easy one, the

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Superficial palmaris longus.

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Now, not everybody has one.

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They can be bifid, they can be

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trifid, or they can be absent.

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Why is that important?

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Because the palmaris longus is one of the structures

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that is used most commonly as a graft in various

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parts of the body, especially in the hand and wrist.

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Now, if you go to the carpal tunnel space, you

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can find the median nerve and work backwards.

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That's one of our hypo intense structures, but

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it's not as hypo intense as the black tendons

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that are running in a long wise fashion.

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And we go all the way to the radial side,

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and we find the flexor carpi radialis.

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That's easy.

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We go all the way to the ulnar side,

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and we find the flexor carpi ulnaris.

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That's easy.

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Since we found the median nerve, let's find it again.

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There's the median nerve.

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Let's find the ulnar nerve.

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The easiest way for me to find the ulnar nerve

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is to go distal, find the superficial and motor

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divisions of the ulnar nerve, and then follow

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them more proximally, and there they are.

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That is the ulnar nerve.

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What about the arteries?

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That's a little tougher.

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Usually the artery is wrapped

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around or embraced by some veins.

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There's the radial artery.

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There are two veins on either side.

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The artery has a little bit faster flow.

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The veins have a little bit slower

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flow, so they're a bit brighter.

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The same phenomenon exists in the

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ulnar aspect of the vascular arch.

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There it is right there.

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It's got a little nubbin of low signal inside.

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And we see a few veins around it.

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So we've got the ulnar arch, we've got the

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radial artery, or the radial arch, and now

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we've got these remaining black structures.

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And you can easily pair them up, because now

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you know where the palmaris longus is, the

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flexor carpi radialis, the flexor carpi ulnaris.

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So all the rest of them represent the superficial

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and deep flexor tendons for each finger.

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One, two, three, four.

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Four and five.

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That's pretty simple.

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All we have to do now is remember one more.

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And that is the flexor pollicis longus.

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Now, that may be a little confusing.

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Because we found the flexor carpi

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radialis and it likes to oppose itself

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right next to the flexor pollicis longus.

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As we move from proximal, where they're apart,

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to distal, where they sort of come together.

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But the flexor carpi radialis stays outside of the

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carpal tunnel and inserts on the base of a carpal bone.

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Whereas the flexor pollicis longus keeps on going, and

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going, and we stop right here, but it goes on to the

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thumb, and we'll see its insertion at a later date.

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So don't confuse those two.

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An introduction to the short axis projection.

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Focusing on the palmar, ventral,

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or anterior aspect of the wrist.