I'm Adair Call, and we'll be performing a live ultrasound evaluation of the dorsal wrist. This video is not meant to be a comprehensive review of this topic. Rather, our objective is to cover the core competencies as outlined in the AMSSM Recommended Sports Ultrasound Curriculum for Sports Medicine Fellowships. For evaluation of the dorsal wrist, we'll, again, have our patient positioned seated across from us with their hands supported on a pillow so there can be a little bit of wrist flexion. We want to begin at Lister's tubercle, which will be our bony landmark that will be kind of our home base for the dorsal wrist evaluation. This is usually readily palpable on the patient, so you can palpate it and then place your transducer right on that location. Lister's tubercle is going to divide the second and the third dorsal wrist compartments. And so this is our way to keep organized so that we know where we're at. So moving from Lister's tubercle, we'll then move radial, which is on the left side of the screen. And then we'll come into the second dorsal wrist compartment. So here we'll see the two tendons of the extensor carpi radialis longus and brevis sitting within the compartment. With any of these dorsal wrist compartments, we can follow them all the way up to the muscle tendon junction. We can follow them all the way down towards their insertion. And we sort of follow them in those locations as clinically indicated. A lot of the pathology that we'll be evaluating will be focally over the dorsal aspect of the wrist. So as we continue to move radial from the second, now we're going to move over into the first dorsal compartment, which we see sitting right here. And this is going to be where we'll assess for the querbain's tenosynovitis. And we'll have our abductor pollicis longus and our extensor pollicis brevis tendon. As we move down a little bit towards the hand, we can see the two tendons separately a bit better than we can at the wrist. As we move back up, sometimes you can appreciate the two tendons. Sometimes it looks sort of like one tendon in this location. So there are a lot of variabilities here. You can often see multiple slips of the APL through here. And so just take that into consideration. Always determine pathology based on the clinical context as well. You can perform a Doppler evaluation here looking for tenosynovitis of that area. So we can put the Doppler on to see if there's any flow around the tendon, which you commonly will see in a d-querbain's tenosynovitis. From this location, we can follow this first dorsal compartment tendons approximately. And we'll see them right here cross over the second dorsal compartment tendons right here. So that's the first crossing over the second right at this location. And that's a potential spot for intersection syndrome. And so we can see on our model here where that occurs on the forearm. It's a relatively common condition we'll see in rowing athletes and other athletes where there's thought to be a friction syndrome of the first and second crossing over. So as we continue to move down, we also want to evaluate as we're looking at the first dorsal compartment, we want to be able to evaluate for the superficial radial nerve as well. And so there's some variability as to where the nerve will split. But we can see in our patient here, right here as we move proximal, is the superficial radial nerve together. So again, that honeycomb type appearance and short axis. And as we move distal, we'll see the nerve here branch into two divisions. And then one division is moving towards the ulnar side. Our other division here is going to come down. And it's going to move over right here to the radial aspect of that first dorsal compartment tendon. So it sits right there. So there's a lot of variability in terms of where these are going to cross and where they're going to move. So you should always just find the nerve as far proximal as you can and then trace it down so that we know where it is in relation to that first dorsal compartment. So we'll move back over to Lister's tubercle now. We looked at the first and second compartments. Now we'll look at the third, which is our extensor pollicis longus, which sits right here. And so if we follow this distally, we'll see that it moves over the second compartment right here. And so this is a spot that you can, again, see another intersection syndrome. This would be the distal intersection. And you can appreciate on our model that this occurs much lower than where the proximal intersection syndrome occurred. So back to Lister's tubercle, we'll now move further ulnar to the fourth compartment, which we see here. And this will include our extensor indices and our extensor digitorum, as well as our posterior interosseous nerve, which is going to sit deep within the fourth dorsal compartment down here. So we can, again, follow any of these all the way distally towards their insertions or proximally, as indicated. We'll continue to move over and evaluate the extensor digiti minimi, which is our fifth dorsal compartment tendon that sits right here. And then the last will be our sixth, which would be our extensor carpi ulnaris. And so for our extensor carpi ulnaris, oftentimes it's difficult to get an adequate view of the tendon with the patient in this position. So what we want to do is come up proximally to the ulna where we see this characteristic groove. And we can see our model here actually is partially subluxed. And this is a normal finding. And so you can see the tendon right here sits. And we're coming out of the groove a bit. Here's the groove. And this tendon can typically sublux as much as 50% and still be considered normal. So we can bring the patient into some pronation and supination to evaluate stability of this tendon to see if it actually dislocates. And we'll look at that a little bit more on the ulnar exam. But one way to do that is to actually change the positioning of the patient. And you can do it a few different ways. You can bring them up into a position where their elbow is rested on the table, which will demonstrate in the ulnar exam. Or you can simply just move them over, as we're doing here, into a bit of hyperpronation. And then we can follow this tendon along from its proximal to distal aspects. So here, we're able to see that with that pronation, we're able to kind of locate it in the groove a bit better. And if we bring it into supination, it'll be a little bit challenging to show here. But the tendon may move a bit on us. And again, we'll show this a little bit better in the ulnar exam with a more optimal positioning of this tendon. So those are the six dorsal wrist compartment tendons. We'll move back to Lister's tubercle and then evaluate the joints. And so if we come back to the tubercle here and we move distally, we'll see the tubercle will go away. The radius will go away. And then we're going to fall in to the proximal carpal row. And this will be our scaphoid here and our lunate here. And so we can evaluate the dorsal scapholunate ligament, which sits right in this location here. So this is another area that we can see injury, post-trauma, post-fall on an outstretched hand. So we can evaluate the joint here, the ligament. And you can do some dynamic stress maneuvers here, looking at the ligament as well. So we can bring the patient into ulnar and radial deviation. And here, we can see the ligament tense. We don't see any gapping at the joint. So we're looking right here for these bones to gap and for any movement, really, at that ligament. And we can see things move. We see some subtle motion and a small amount of physiologic fluid within that joint below. But everything looks very stable. Any of the other joints of the wrist can be evaluated. Similarly, we can turn into a long axis view where we have the radius on the right. And then we can look at the carpal joints for any evidence of tenosynovitis, particularly in rheumatology patients or any other source of traumatic or asymmetric swelling in this location. So all the joints can be evaluated individually as clinically indicated. The other thing to mention in the region of the scapholunae is this is a very common location to get dorsal ganglion cysts. And so often, those ganglion cysts will be coming from the radiocarpal joint. And they'll be located somewhere around this location. So this is something they should look for as a hypo- or anechoic cystic structure around this location. It's very common in the dorsal wrist. And that completes our evaluation of the dorsal wrist.

2nd Edition, CASE 18

2nd Edition

Hand and Wrist

ultrasound evaluation

dorsal wrist

sports medicine

tenosynovitis

Doppler imaging