Transcript
josh MacDonald: I'm Josh McDonald.
Miranda Materi: and I'm Miranda Materi and we are Hand Therapy Academy.
josh MacDonald: Let's talk a little bit about PIP joint ligaments, specifically accessory and proper collateral ligaments testing for them, splinting for them, treatment, all kinds of good stuff.
Miranda Materi: Yeah, so we know with these collateral ligaments, they are on the radial and the ulnar side and they are basically providing the lateral support to the PIP joint. So you have the accessory ligament, which is on the basically the volar surface or more towards the volar side and then the proper, which is more on the dorsal side, not necessarily the dorsal side, but dorsal to that ligament, if that makes sense. And it's kind of hard to, I think, explain this because you don't have the visual in front of you, but you can certainly look it up and see these proper and accessory collateral ligaments. And I think a lot of times when we get them from the doctor, it'll just say collateral ligament, right? And you're like, okay, well, which one is it and why does it,
Miranda Materi: Why does it really matter? And I think, you know, as people studying for the exam, it matters for that reason.
josh MacDonald: Yeah.
Miranda Materi: And in your clinic day to day, it has some impact, but we'll talk a little bit about what that is. But basically, how do you test the proper and the accessory collateral ligaments when you have these patients?
Miranda Materi: And you're basically providing that lateral stress with the joint and extension. And then you're going to do it again with the joint inflection because it tests the the different ligaments. So when it's in flexion, it tests the proper, and when it's in extension, it tests the accessory.
Miranda Materi: So you're basically putting tension on it when it's in that position. So if you want that if you have a patient that comes in with, usually it'll be like joint sprain or collateral injury, then that gives you an idea that you can test further to help determine which one it is. So if you're going to need more protection, you're going to split them in that position that provides the least amount of strain on it, right? So if it's tight, when it's in the flex position, you're probably not going to put them in that position long term because that's goingnna put more stress on that ligament.
Miranda Materi: don't know if that makes sense. And so how do patients injure these collateral ligaments? It's generally by like an angular force. So you don't picture someone grabbing your finger and twisting it. That's how these patients get get their injuries. and so And if the ligament is evulsed, it usually evulses proximally as opposed to distally. So I think with the molar plate, it goes distally, but these ligaments go the other direction. And does that really matter? Probably not, but it kind of gives you a picture in your mind of when it's stressing, when you're stressing it, which direction those ligaments are going and why they might have pain, where they have pain at.
Miranda Materi: And then another thing I can tell you about the collateral ligaments is you're more likely to injure your radial collateral ligament injury. And that's because of, you know, the radial collateral ligament is more exposed, especially on the The pinching side, so that's or your index finger side. So that's the one that's most likely to be injured or have that angular stress as opposed to the ulnar collateral ligament.
josh MacDonald: right. That's a lot of good information. A lot of stuff packed in there. um I want to go back to the um what position we should splint them in, depending on if it's proper or accessory. Would you splint them in the same general position or would you splint them differently if you tested and discovered one was accessory and one was proper?
Miranda Materi: That is a great question because I think anytime we're splinting the PIP joint inflection, we have to be careful, right? Because we know that the PIP joint has a high risk factor of becoming a PIP joint contracture.
Miranda Materi: So with that, I would split them different. Like what I had a a younger patient that was in an ATV accident and he had a collateral ligament injury.
Miranda Materi: And we did end up putting him in a little bit more flexion. And if he, I was thinking about if he was an adult, I wouldn't have put him in flexion. He just didn't have, it wasn't stable when he was in extension, if that makes sense.
Miranda Materi: So I check, it's very much, you know, kind of an intuitive common sense thing, but if they're not stable, you're not going to put them in a position that's unstable, right?
josh MacDonald: Yeah, yeah.
Miranda Materi: So, and then you have to take into account this patient's age, how likely are they going to end up with a PIP joint contracture? Are they coming in frequently to see me where I can monitor if the PIP is getting stiff, right? So I might put them in that in that position for a week and kind of see how they do and see if their PIP joint is getting stiff.
josh MacDonald: Yeah. And that's an interesting thought too, that just because we put them in one position on day one, doesn't mean that's the position they're going to stay in for the six weeks or eight weeks or however long they're going to be in that splint for. it Like you could put them in like, Hey, they're really unstable in extension. So I'm going to put them in flexion, but then on week two or three, they might be way more stable in extension and I can pull them out of that flex position so that they don't develop that, that contracture into flexion, 30 degrees or whatever it is.
josh MacDonald: But you can change that position. Whether I remake that splint or I try to adjust the splint they already have, like there's there's some room for for adjustment there.
Miranda Materi: Yeah, and I think this is where our clinical judgment comes in, right? So Josh and I have been practicing for a long time, so I think we've seen a lot of these things and how they play out, right? You kind of get to feel for them So if you're, say, ah new to the field and you're taking the test, right, that's what people always want to know.
josh MacDonald: Mm-hmm.
Miranda Materi: Well, what's the test going to say? Well, the test isn't going to just give you, you know, this black and white. Is the accessory tight in flexion or extension? It's not going to ask you that.
Miranda Materi: It's going to tell you, hey, I tested this patient inflection and they had um less stability than they did in extension. What lingam is involved, right? They're going to ask clinic based questions that help guide you to that answer. So I always say, like, I don't know what question they're going to ask. I can only provide you like this is what it is. And these are the different scenarios of how it could play out.
josh MacDonald: Yeah. Yeah. And if you were to splint someone in flexion, like this, this patient that you had, about how much flexion would you say? Are you doing 30 degrees?
Miranda Materi: Yeah, 20, 30.
josh MacDonald: Yeah. Yeah.
Miranda Materi: And they they've done studies showing, you know, like we can measure them with a goniometer and say, hey, this is 20 degrees flexion. Is it really? You would really have to have x-ray imaging to see, right?
Miranda Materi: If that is really the true position because you have this edema and stuff like that.
josh MacDonald: Yeah.
Miranda Materi: So it's very much like I eyeball and say it's around 20, but I'm eyeballing it not for what degree of flexion. I'm eyeballing it for what degree is stable, if that makes sense.
josh MacDonald: Yeah. Yeah. and And I like that for a lot of our patients who have like a vulgar plate injury. I mean, there's now some research saying you could plant you can splint a patient with a vulgar plate injury in full extension with that dorsal blocking as long as they can't hyperextend. But when we were doing it in 30, I wasn't really pulling out a goniometer. I was just putting him in that gentle protected position. Because if I go a full 30 and they start to get tight, that's way harder to recover from than 20.
josh MacDonald: But they could still be protected in 20.
Miranda Materi: Yeah.
josh MacDonald: Yeah. Yeah.
Miranda Materi: Yeah. And I think a lot of times we try to get into, we think about the biomechanics and what we think it really is, but really we need to think about it, the biomechanics and the patient, right? It's really that combined thing. And I think that's what is the fun part about our job is blending the evidence and the biomechanics with that patient, the individual patient injury.
josh MacDonald: and doing that where you have a pediatric patient, maybe they're 16 or 17 and I'm comfortable splitting them into different parameters than I would my 54 year old female who's a smoker and maybe diabetic. Well, I'm to put them in a way different parameter. And maybe I apply those treatment guidelines differently than I would for the the kid who's a nervous Nelly and they're going to behave and they're going to heal well and they've got no comorbidities.
Miranda Materi: Yeah, yeah, it's really that individual patient.
josh MacDonald: Yeah, yeah. Very cool. All right. We could go on and on about the PIP joint, but we're going to keep it just to ligaments today. So hit us up if you have any questions. You can email us at info at handtherapyacademy.com or our social media platform at Hand Therapy Academy.
