Michael Smith, MD (Host): Welcome to Pediatrics in Practice, a CME podcast. I'm Dr. Mike. And with me is Heather Barnes, a nurse practitioner in orthopedic surgery, and Angie Vanderpool, a pediatric nurse practitioner in orthopedics and sports medicine, all from Children's Mercy. Today, we're going to be discussing limping and its clinical red flags.

Welcome to the show, Heather and Angie. Heather, I'm going to start with you. When should a limping child raise concern beyond a minor injury? And if you could highlight some of those key red flags physicians should be watching for.

Heather Barnes, DNP, APRN, CPNP, ONC: Sure. I think some of the things that are concerning when a child is limping is if they're refusing to weight bear. That's usually an indication that there has been an injury. And if there hasn't been an injury, then it's a little more suspicious of why are we not wanting to bear weight.

Another concern certainly is any ill symptoms or fever that could indicate that there might be some sort of inflammatory or infectious process going on. If they're complaining of pain without any known injury, if we're noticing that their gait is abnormal or different than it was previously, if they're not behaving the same, if their activity level has changed, they're not doing things that they normally would do because they're in pain or uncomfortable, or sometimes their age, they can't explain what's going on. These are things that are red flags that should indicate maybe kind of look into something a little bit further.

Host: Yeah, I like the idea of the, the weight-bearing being a big one. I know that's probably helpful for parents. You know, if your child injures themselves, but they still want to get up and run around and that, you know, that's probably not so bad. But if they don't want to move, if a kid doesn't want to move and play around, that's probably a good red flag, I would assume. Angie, let's move to you. What historical clues or symptoms help differentiate a benign cause of a limp from a more serious condition?

Angie Vanderpool, APRN, CPNP, ON: Well, if you don't know of any particular injury, then like a recent illness, if they've had a cold or respiratory infection if they have a persistent pain and no cause that you're aware of. It doesn't count if they started limping after they were running around with some kids and you didn't see them for a while, because they may have hurt themselves then. But if you know, especially on a really small child, that it just kind of came out of the blue, all of those are concerns.

Host: When you look at limping in children, you know, obviously, you have the younger kids that are just getting moving. You have some of the older kids, preteens and all that kind of stuff. What are some of the most common causes of limping in, say, the younger kids versus an older child?

Heather Barnes, DNP, APRN, CPNP, ONC: Sure. So, more common reasons in a younger child, a toddler or, you know, like a preschool age child is an inflammatory condition, something like transient synovitis or possibly an infectious cause. Commonly in this age group can be like a septic arthritis or a joint infection. So, those are the big things that we worry about in those age groups.

A little bit older, maybe your pre-adolescent, they can have a condition that we see in orthopedics called a slipped capital femoral epiphysis or a SCFE. And that's a problem with the hip, that is a common reason—common in orthopedics—that that aged child would be limping or complaining of pain in their hip or their knee.

So, just to kind of give a little variation of what I might be thinking of if I see somebody in a certain age group, these are the things that my mind is wanting to look into and make sure that's not what we're dealing with.

Host: So Angie, when you're doing a physical exam on a child who's limping, are there particular pain patterns you're looking for, location, severity, timing, that if you find on physical exam are raising your concern?

Angie Vanderpool, APRN, CPNP, ON: Yeah, I think joints are always an issue if they have an irritable joint or a painful swollen joint, pointed redness, warmth, sudden onset, how long has it been going on; refusal, of course, to weight bear; increasing pain, and then how they look. I mean, it's kind of just seeing what they're willing to do and if you can pinpoint where it's coming from.

Host: And with that physical exam, how is it different, let's say, with like a non-verbal child, one who can't really express themselves versus an older child? How do you manage that difference?

Angie Vanderpool, APRN, CPNP, ON: Very carefully. Getting them to do something, I mean, whatever you can get them to do is hard for the little ones.

Heather Barnes, DNP, APRN, CPNP, ONC: I think, in my experience with the little ones, even developmental delay or just age and, you know, they don't communicate with you well yet, is watching them during your physical exam for changes in their facial expressions or, you know, do they pull away, you know, if you're palpating or examining them, trying to find an area maybe of tenderness that you're really watching them to see their reaction. That's very helpful.

Host: I kind of want to put this together for the community pediatrician. We've mentioned some red flags here and there, some things that might raise concern. So Heather, I'm going to stick with you. Can you give us a nice summary of those red flags that a community pediatrician should really get some imaging, get that referral going, et cetera?

Heather Barnes, DNP, APRN, CPNP, ONC: Something that I see fairly often in my practice is that toddler, preschool age child who not sure if we had an injury, but they're not interested in weight bearing normally, maybe they're limping, maybe the parents think they're not weight bearing. But on exam, you know, maybe you can get them to weight bear, they just don't want to or they don't like it.

And then, you kind of get into the history a little bit more. Was there a recent illness of any kind, an ear infection, strep throat, history of fever, any of those kind of things? Then that's something that might warrant a little bit more investigation and an X-ray or possibly a lab workup to look for any sort of inflammatory or infectious markers.

Host: Speaking of you mentioned X-rays, you know, imaging strategies I'm sure play a pretty big role. So Angie, how often do you jump right to imaging as a tool to help you diagnose? Or in some cases, is it okay to maybe delay that based on your physical findings?

Angie Vanderpool, APRN, CPNP, ON: I have a tendency to go quickly to X-ray. It's a lot less invasive than getting lab work and a lot easier than doing that on a small child if I don't know for sure what's going on. And a X-ray really can clear the air on what happened. Sometimes you'll have a child that's refuses to walk , you get an X-ray and you find, well, there's a needle in their foot. So, there's a reason for it, but nobody saw it happen. So, an X-ray has its own ability. It tells you if there's a small buckle fracture that may be contributing to it.

Host: So, X-ray is great for the bone fractures, dislocations. What about if you're more worried about a tissue, musculoskeletal? How often do you move to, say, maybe MRI?

Angie Vanderpool, APRN, CPNP, ON: As a general rule, you have to get an X-ray first because you're going to have to justify getting an MRI.

Host: But they're still part of your tool bag in case you needed to do that, the MRIs, I'm sure.

Angie Vanderpool, APRN, CPNP, ON: For sure.

Host: So, Angie, sticking with you, what conditions are commonly missed or diagnosed late in children presenting with limp or say some unexplained pain?

Angie Vanderpool, APRN, CPNP, ON: I think in adolescence, the one we're all really worried about the most is a slipped capital femoral epiphysis. And if that is found on a teenager or a preadolescent is usually when you'll see it, because they're not skeletally mature, and that can be a big deal and cause a lot of long-term problems.

OCD lesions, sometimes those kids will be limping for quite a while before anybody gets an X-ray or notices what's going on, and part of it's because they don't complain all the time. They complain off and on. In a younger child, Perthes, Legg-Calve-Perthes. So, six to kind of school age, 10 years old, school-aged child. And again, hip pain comes and goes, but it seems to really limit them. Septic arthritis, that's something that as a general rule, they're sicker and gets caught a little quicker. Tumors, leukemia, and rheumatologic causes.

Host: Heather, when should pediatricians consider a septic cause? Whether it be infection, inflammatory disease, malignancy in a child with limp. What are some of those red flags that would make you think to go down that cancer pathway, for instance?

Heather Barnes, DNP, APRN, CPNP, ONC: Well, I think, you know, if we're talking about a neoplastic concern, so, you know, you're kind of checking off your box of differential diagnoses and kind of not getting anywhere of finding a reason. You know, I think that one's always got to be on that differential when there wasn't an injury.

And before you've done any labs or radiographs, you have to consider that as a potential. Obviously, that's not that common, but I don't think it's something to just dismiss. So for example, somebody who's had pain, maybe they show up at the pediatrician's office. They've had pain for a month. It's starting to interfere with their activity. They haven't been sick. They didn't have an injury that we're aware of. Maybe they start to complain of asking more questions like, are they having pain at night?

If we're thinking about a rheumatologic cause, are we having pain in the morning, like stiffness when we wake up, and then it gets in better as the day goes on? So, just some different thought processes when you're kind of looking at a differential diagnosis list of why somebody might be limping and did not have an injury.

Host: This has been fantastic. I really feel like I've learned a lot from both of you, and I want to thank you for coming on. I'm going to start with you, Heather. Do you have any last words for the listening audience?

Heather Barnes, DNP, APRN, CPNP, ONC: For pediatricians, I think it's okay to continue to monitor your patient. But if your patient's not getting better, if they're not improving, because I think it's always okay to have time if it's appropriate. But if we're still not seeing an improvement, then that's when, I think, maybe referral is appropriate or, you know, getting labs or X-rays or those kind of things just to look a little bit further into why symptoms aren't resolving.

Host: Angie, any last words?

Angie Vanderpool, APRN, CPNP, ON: Make sure you use the resources that are available and feel free to reach out to people that have more experience in certain areas if you need help.

Host: Fantastic. Again, thank you guys for coming on. Very helpful information I know to the community pediatrician. So, thanks for all of your time that you spent with me today. That was nurse practitioners Heather Barnes and Angie Vanderpool. As a reminder to our audience, you can claim your CME credits after listening to this episode by visiting cmkc.link/cmepodcast and clicking the Claim CME button.

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