how to make gliding joint at the wrist of hand step by step
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Answer:
This wrist joint is this joint here between the radius and an articular disc which lies at the end of the ulna and it attaches to the base of the styloid process. It’s between the radius and an articular disc at the end of the ulna and between the proximal articular surfaces of these three carpal bones – the scaphoid, lunate and triquetral bones.
The wrist joint is a condyloid synovial joint. You get flexion, extension, abduction, adduction and you get circumduction, which is a combination of all these movements. Abduction is movement in this direction. Adduction is movement towards the midline. Flexion and extension – flexion is up this way and extension is back this way.
It’s just worth pointing out that the styloid process of the radius actually extends further, extends more distally than the ulnar styloid process. This actually means that the wrist joint is more limited in its range of movement in abduction because the styloid process longer and it limits this movement a bit. Because of the more distal radial styloid process, the hand cannot abduct as far as it can adduct because the ulnar styloid process over here doesn’t extend so far.
The wrist joint is a radiocarpal synovial joint. It involves the three carpal bones here, the proximal carpal bones – scaphoid, lunate and triquetral. It involves the distal end of the radius and there’s an articular disc which lies over the ulna. It’s a radiocarpal synovial joint.
Let’s just quickly take a look at some of the ligaments in this area. You’ve got collateral ligaments. You’ve got ligaments connecting the radius and the ulna to the carpal bones, so you’ve got radiocarpal and ulnocarpal ligaments. And you’ve got ligaments on both sides. We’ve got palmar and dorsal ligaments. And then you’ve got ligaments at the end of the radius and ulna which connect these two bones together.
At the distal end of the radius and ulna, you’ve got this ligament connecting the bones on the palmar surface. This ligament here is the palmar radioulnar ligament. If I just rotate around and we look at the dorsal surface, you’ve got the dorsal radioulnar ligament.
Then we’ve got the collateral ligaments. We’re looking laterally at the wrist here and you can see a ligament connecting the styloid process of the radius bone to the carpal bone. This is the radial collateral ligament. If we’re looking at the medial aspect of the wrist, you can see the ulnar styloid process connects to the carpal bones, so this is the ulnar collateral ligament.
We can just see these ligaments here which run from the radius to the carpal bones and we’re looking at the palmar surface, so these are the palmar radiocarpal ligaments. Likewise, we’ve got palmar ulnocarpal ligaments. These run from the ulnar bone to the carpal bones.
If we just look at these in a little bit more detail, they can be broken down into two parts. The palmar radiocarpal ligament connects from the radius to the capitate bone, so this particular ligament is called radiocapitate part of the palmar radiocarpal ligament. And then you’ve got this other part which connects from the radius to the scaphoid and the lunate. This ligament is called the radioscapholunate part of the palmar radiocarpal ligament.
It’s the same with the ulnocarpal ligament, the palmar ulnocarpal ligament. It’s got two parts. One part connects to the lunate, so it’s called the ulnolunate part. And the other part connects to the triquetral bone, so it’s the ulnotriquetral part.
What you really need to take away from this part is just that there’s a radiocarpal and an ulnocarpal ligament and it’s on the palmar surface, so it’s palmar ulnocarpal and palmar radiocarpal ligament and they have two parts.
If I just rotate the model around, we can just look at the back of the hand and there’s only a radiocarpal ligament on the dorsal surface. There’s one dorsal radiocarpal ligament.
Those are the ligaments that you have at the wrist joint. You’ve got two collateral ligaments. You’ve got a radial and ulnar collateral ligament. You’ve got the two ligaments at the distal end of the radius and ulna. You’ve got the dorsal radioulnar and the palmar radioulnar ligaments.
And then on the palmar surface, you’ve got palmar radioarpal ligaments and palmar ulnocarpal ligaments, which are broken into those two parts.
And then on the dorsal surface, you’ve only got a ligament connecting the radius to the carpal bone. You’ve got a dorsal radiocarpal ligament.
Now we’ll just look at a few of the other joints that we have in the hand. After the wrist joint, we’ve got the carpal joints. These are the joints between the proximal and distal end of carpal bones. You can see that there are quite a lot of ligaments here, but there’s quite limited movement at this joint, but there is a little bit of movement and it helps to position the hand in abduction, adduction, flexion and extension.
Explanation: