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S2D: The Symptom to Diagnosis Podcast - Episode 10: Back Pain
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S2D: The Symptom to Diagnosis Podcast - Episode 10: Back Pain
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Language: EN.
Segment:0 .
DR. CIFU: I'm Adam Cifu.
DR. STERN: And I'm Scott Stern.
DR. CIFU: And we're here with, believe it or not, episode 10--
DR. STERN: Wow.
DR. CIFU: -of the Symptom to Diagnosis podcast.
DR. STERN: Well, time flies.
DR. CIFU: Doesn't it ever?
DR. STERN: Well, our topic of the week is back pain, and Adam, you are the expert of the day, and do you have a case to present to me?
DR. CIFU: I certainly do. This case was from two years ago.
DR. STERN: Okay.
DR. CIFU: Picture yourself in a nice January in Chicago.
DR. STERN: Okay, that's impossible. [chuckles]
DR. CIFU: And I'm in the office and a woman appears on my schedule, 75 years old, I've never seen her before, never met her before. She was actually the mother of a patient of mine and the patient called and said, "Hey, will you see my mom? She's got back pain." And the story she tells me is that she went out to throw away her garbage on a Sunday before the garbage men came to pick it up on Monday, and we have these big dumpsters in Chicago, right?
DR. CIFU: And she goes out and she tries to open it and she can't open it because it's frozen shut, and so she pushes, she pushes, she pushes, it flies open once the ice broke and then she got this terrible pain across sort of the middle lower part of her back. This was about three days before. She's been totally hobbled, like unable to lie in her bed, she's been sleeping on the floor, she's miserable, and she comes in.
DR. CIFU: Past medical history, she's got some high blood pressure, she smoked for a million years and she had breast cancer and no really history of this, but had a total mastectomy, mastectomy like we wouldn't do anymore, 20 years before. And seeing her, she was one of those people, she walked in kind of cautiously, right? You know how those people with back pain move.
DR. STERN: Right, right.
DR. CIFU: Very cautious getting up on the table. Normal vitals, her gait was actually normal, though a little antalgic and she had limited range of motion of her back. If I tried to extend her flexor, she had a lot of pain, but her neuro exam was actually normal. I did reflexes, I did strength, sensation, all of that was fine, and her straight leg raise was limited by pain and stiffness, but none of that good shooting pain.
DR. CIFU: So you're with her in the office. What would you, Dr. Stern, have done with her?
DR. STERN: Well, just a couple of questions. So, one, is she tender over the spine?
DR. CIFU: She was. It wasn't like central tenderness, but actually there was central and lateral, probably kind of, I don't know, let's say L2 to L4 range. That was all pretty tender back there.
DR. STERN: Well, it's certainly a common problem, right? She does have, and while back pain while people are lifting something is incredibly common and often it's just related to a strain, there's a couple of concerning features for her. One, she's an elderly woman. I'm going to start changing the age range for elderly, but she's there. You didn't mention her weight, and did you say she was a smoker?
DR. CIFU: Yeah. So she's got a long history of smoking and she's I think back then-- I can't remember if she's actively smoking, but she's got a good 100 pack years under her belt.
DR. STERN: And her weight is what?
DR. CIFU: She was a pretty frail lady. She was, let's say 5'3", 110 lbs.
DR. STERN: Right, so she has multiple risk factors for an osteoporotic compression fracture. She's thin, she's elderly. I don't know, I haven't heard of any history of glucocorticoid use or steroid use that you've mentioned, but certainly bending over, pushing hard, having something suddenly occur in a woman with this demographic range puts an osteoporotic compression fracture high. She also has a history of breast cancer and it's interesting because it's 20 years ago.
DR. STERN: Breast cancer is kind of a funny cancer that occasionally recurs much, much later. This is definitely on the long side, but you know, it's not out of the list, I don't think. There are reports of people with bony mets showing up quite late, and so I think she's got two possibilities there that are both very concerning, and so even in the absence of neurological finding, I would feel compelled to-- What I'd probably do in the office is just because I can get it immediately is get a plain film just to see what it looks like, but I'm going to get an MRI almost no matter what that shows to make sure that if there is a compression fracture, it's not a malignant compression fracture.
DR. CIFU: That's good, sounds good. Just maybe to highlight two of the things you said. The breast cancer issue is something that I thought about and I feel exactly the same way. Just about any other cancer, sure, 20 years out I wouldn't think about, breast cancer, I would still think about, and the steroid use, you know, she was a long term smoker. Often people are not on chronic steroids, but a lot of people with bad COPD are on so many sort of tapers that they end up essentially being on chronic steroids.
DR. STERN: For sure.
DR. CIFU: So good, okay. Let's stop there.
DR. STERN: Okay.
DR. CIFU: Because the X-ray is the turning point.
DR. STERN: All right. Well, I think then we're going to take a deep dive and will you start us off with five key points about how we should approach diagnosing back pain?
DR. CIFU: Sure, I would love to.
DR. STERN: Okay.
DR. CIFU: So point one is, I think to admit to yourself that most back pain is boring.
DR. STERN: Indeed.
DR. CIFU: When we decided that podcast number 10 was going to be back pain, I think we both yawned simultaneously.
DR. STERN: [chuckles]
DR. CIFU: And so you got to kind of commit yourself to taking it seriously. I tell myself this and I tell my students this a lot, that whenever you find something either intimidating or boring, you should just really try to learn about it because that makes things that are intimidating less intimidating because you know it, and the things that are boring, often you learn interesting things and knowing more about it makes it more fun to take care of.
DR. CIFU: So the things to really, really learn for back pain is know the serious causes well, and the serious causes are things that are caused really by systemic or visceral causes or those that can risk really like, imminent neurological compromise. And on the other side of things, have a really good sense of what common interventions are and what happens when you do them. So if you can spend a day with a physical therapist managing people with back pain, or if you have someone who had musculoskeletal, mechanical back pain who got better, really talk to them.
DR. CIFU: How did this unfold, how long did this take? And you'll learn what the physical therapists do, you'll learn that most mechanical back pain actually takes like, 4-12 weeks to get completely better and you'll be able to really counsel the patients well.
DR. STERN: That's great. Have you actually spent a day with a physical therapist in the physical therapy clinic?
DR. CIFU: So I did, only because 15 years ago I developed terrible back pain.
DR. STERN: I see, I see.
DR. CIFU: I was out for a run and it was like, I was struck by the hand of God with this just horrible pain, and it gave me so much more empathy for people with back pain. It made me recognize how people move with back pain, and I learned so much from the physical therapist at that point, and I learned actually then not only to use the physical therapist for therapy, but recognize that they're actually incredible diagnosticians, and so it's really altered my practice.
DR. STERN: Okay, well that was a useful point. All right, what's your next point?
DR. CIFU: Okay, second key point is framing the diagnosis, and I think both of us have gotten to the point where we always spend some of these points talking about we frame the differential dignosis.
DR. STERN: Right.
DR. CIFU: So I think the best way to frame the differential diagnosis and it's how it's framed in the Symptom to Diagnosis textbook is to think of it as musculoskeletal causes, systemic causes, and visceral causes. So musculoskeletal causes are the most common cause. 95% of those are non-specific, basically, I don't know what caused this, it's just back pain.
DR. STERN: Right.
DR. CIFU: But there are some specific causes, right? Radiculopathy is usually from nerve root compressions, maybe from a disc or osteoarthritis, spinal stenosis, cauda equina syndrome. There are systemic causes, which are often bad things like malignancy or infections or osteoporotic fractures or inflammatory arthritides and then there are visceral causes, which are much less common, but can be really horrible, and so this is like say, a AAA causing back pain, retroperitoneal adenopathy causing back pain, pelvic pathology, maybe an ovarian cancer, or even GI causes, right?
DR. CIFU: We all know that pancreatitis might radiate through to the back.
DR. STERN: I mean, it's really a good point about putting that with your other point that it can be boring because some of the diseases on this list are really life-threatening, and the trouble is that 98% of the time it's not, but when you miss it, it's a disaster.
DR. CIFU: Right.
DR. STERN: And I had a lady several years ago who had an epidural abscess and we thought her fevers were coming from pyelo and boy, it was a close call. She did okay, but it was quite close. We did not jump on it as quickly as we should.
DR. CIFU: That's it, I mean, the case of so much of medicine that you can be not just good, but you can be pretty good just always going with the obvious because the bad things are rare and so it takes a lot to not over-evaluate people, but also not miss the rare things when they cross your threshold.
DR. STERN: That would be the perfect compromise. All right, third?
DR. CIFU: Third key point, red flags. I guess it's a good time to go into that. So if there are no red flags, you don't need to image back pain, but you need to know what the red flags are to know when you need to image it, and the red flags that I always keep in mind are cauda equina syndrome and that's often people presenting with back pain and bowel or bladder symptoms or saddle anesthesia, infection, and so that might be back pain with fever, or it might just be back pain with a known other infection, maybe which is even being treated, malignancy, especially active malignancy, compression fractures, Scott, you brought up, you've certainly brought that up in our case to see if this person was at risk, lumbar radiculopathy, I think I'm going to talk about this later.
DR. CIFU: Often, lumbar radiculopathy doesn't actually need imaging, but you should consider if it does, and then inflammatory arthritis, which is on every list though, and that's something you don't see a whole lot.
DR. STERN: No, that is uncommon, right. You've got two more.
DR. CIFU: Okay, my fourth key point, because the most common form of serious back pain of that list that we just talked about is lumbar radiculopathy, you got to have basically an automatic exam, okay? Most people who have a lumbar radiculopathy have it because of an L4-L5 or L5-S1 nerve root compression, that makes up for 95% of disc herniations in that area. So you need to be able to just shut your mind off and say, I'm going to do an exam which assesses L4-L5, L5-S1, and that's the sensation in those distributions, so that's basically the distributions over the foot, the Achilles reflex and the patellar reflex is actually not that important, right?
DR. CIFU: It's much easier to get, but that reflects 2-3 and 3-4 and you don't get a lot of herniations there. So you really got to get good at Achilles reflexes, testing strength and dorsiflexion and plantar flexion, and I test that with the patient sitting down, but then I also get them up to do heel walk and toe walk because often you'll find subtle weakness having the patient do heel walk and toe walk that I'll miss if I'm just asking them to plantar flex and dorsiflex against resistance.
DR. STERN: And I'm sure you'll add a straight leg raise to that exam.
DR. CIFU: Yes, I guess I would say I really always do. I mean, I don't always do with back pain, right? But I certainly always do it in someone who's got radicular pain going down there.
DR. STERN: And the only thing I'd add to that is you mentioned how important it is to do the Achilles reflex properly, and that often requires that you gently push up on the foot as you tap and don't have them lift it because then it's not going to work at all, right? I also like the idea of a triggered kind of physical exam. For a lot of symptoms that we talk about, knowing this is the exam I do, and putting it in your brain so it doesn't require a thought, but you get exactly the information you want is I think, that's invaluable.
DR. CIFU: And it's sometimes true for the history, too. I used to say, though this makes me sound really old, but if someone says, "I'm having trouble swallowing," I'd sort of put in a cassette tape and it's like, these are all the questions I'm going to ask. Now I guess it's you flip on your MP3 or MP4 or whatever.
DR. STERN: Pretty soon it will be a chip in your brain.
DR. CIFU: I know, if only. So my fifth and final key point is really obvious and stupid, but it's just remember zoster, right? If you have someone come in and they're complaining of back pain and you don't actually look at their back, you're going to miss something really easy, and also if you're going to be successful in treating zoster, you're going to recognize it early and you're going to feel like a total dummy if you don't notice it, and then the person calls you two days later and say, "You know, I have a rash on my back," and then you're like, A. I missed the diagnosis, and B. I missed the window to actually give therapy when it's effective.
DR. STERN: That's just embarrassing.
DR. CIFU: Yeah.
DR. STERN: I always think you should look at wherever it is somebody has pain, right?
DR. CIFU: I know that, I know that. I've made the mistake though, I have to admit.
DR. STERN: All right. So let's go back to the case. What happened with this woman?
DR. CIFU: So I did get an X-ray on her and I was thinking, given her size and the mode of injury, I was sort of thinking, I bet this is just muscle spasm, but I think compression fracture is really a possibility here and it turned out that she had somewhat demineralized bones, she had no compression fracture, she actually had very little arthritis in the back as well, but the radiologist called me somewhat freaked out.
DR. STERN: Never a good sign.
DR. CIFU: Because she had what he measured just from measuring out the calcifications, an eight centimeter AAA.
DR. STERN: Well, that's terrifying, but I don't know if it's related. Oh my goodness, so the rate of rupture for aneurysms of that size is astronomical, even if they're asymptomatic, but the real question is, is that-- because the history is so clear and suggestive that it happened while she was lifting, and I know of no correlation with AAA with that. Wow, that's terrifying. I suppose I would call a vascular surgeon at this point and ask them what they thought.
DR. STERN: You've got to tell us what happened.
DR. CIFU: Yeah, so I took it as exactly that way that this is truly, truly unrelated but this is a woman who probably had mechanical, non-specific musculoskeletal back pain from what she did. That's what made sense of the history, that's what made sense on her physical exam, and then she is a woman who is a setup for a AAA because here's a woman with hypertension and long term tobacco use. I did have her see the vascular surgeon the next day, actually.
DR. CIFU: Interestingly enough, over the next couple of days as the assessment wore on her back pain resolved, and so it was in fact just musculoskeletal back pain, and she, given a lot of issues and her willingness, ended up having stenting of her AAA.
DR. STERN: Sure.
DR. CIFU: And she did okay. She had to have not infrequent re-stenting procedures over the course of the next few years, but she did not die of her AAA.
DR. STERN: So she never did have an MRI of her back.
DR. CIFU: She never did have an MRI of the back. I think what happened is that we got so distracted dealing with the emergent issue that by the time all that settled down--
DR. STERN: Her back was better.
DR. CIFU: We couldn't even remember that she had back pain, basically.
DR. STERN: That's a little risky, but okay. I think the fact that she was better is why you didn't remember.
DR. CIFU: Yeah, absolutely true.
DR. STERN: Well, that's really interesting and terrifying. Nothing like a AAA to really wake you up in the morning.
DR. CIFU: I wish actually the listeners could have seen your face when I told you that. [chuckles]
DR. STERN: I think my eyebrows hit my forehead, the top of my forehead. Once you've seen one of those! All right, so let's go on and we're going to talk about fingerprints, common misconceptions, pet peeves, everyone's favorite, and random bits of knowledge. So Adam, do you want to start us off with some fingerprints?
DR. CIFU: I do, and actually there are a surprising number of fingerprints in back pain. So the first one that I'm going to throw out there is in a patient who comes in with back pain and has urinary retention that has a positive likelihood ratio of 18 for cauda equina syndrome, okay? But the hard part with urinary retention is you got to ask and you got to have a pretty high suspicion because remember, most people with urinary retention are still peeing, they're maybe just peeing frequently, maybe peeing smaller amounts and so, you really may have to pull that out of them.
DR. STERN: Right, that's a good one. I've actually seen that, and that's also scary. Mine is a prior history of cancer, interestingly enough, has a likelihood ratio of 14.7 for mets as a cause of back pain. So I doubt it's that high in this situation where it's 20 years out, but boy, it's one of those things when-- you know, basically it's a rule of thumb. If somebody has cancer in the past and they come up with a complaint, you better at least first think about whether the cancer is related, whether that's a headache or whatever it might be, ponder it.
DR. CIFU: Right, and if you're in an urgent care setting, you actually just need to ask, have you had cancer before? Because you may not know.
DR. STERN: You may not know, right, totally.
DR. CIFU: On the same theme, history of corticosteroid use, a likelihood ratio of 12 for compression fractures as the cause of back pain. This is not a single episode of steroid use for I don't know, an asthma exacerbation, but people who are either on chronic steroids or who've had multiple courses of steroids over the course of their lifetime.
DR. STERN: And do you happen to know, I assume that risk does not apply to people who've only been on inhaled steroids?
DR. CIFU: Right, that does not apply. As far as we know, inhaled steroids, the effects that we've measured is a very small degree of growth retardation in kids, and an increase in the rapidity in how early people are diagnosed with cataracts in adulthood, but otherwise seems to be pretty benign.
DR. STERN: Hmm. All right, well, my next one is sciatica. So sciatica refers to radicular pain that goes down the leg. We were discussing earlier about how far down it has to go, but it's often a lancinating, severe pain that really stops people in their tracks. I'm more impressed when it goes down past the knees. Sometimes it's a little hard if patients just have tightness in the leg, but nonetheless, the likely ratio is 7.9 for a disc herniation, so doesn't necessarily mean you need to image those patients, but it does give you an indication that it's likely that it's a herniated disc.
DR. CIFU: Yeah, and I think, sciatica's also harder than you think it is, right? Because there, I mean-- I've seen people who come in with calf pain, right? And that's their complaint and it's only with lots of questioning do you figure out that, huh, you know, there's nothing wrong with this person's calf, but it's the back.
DR. STERN: Right, I've seen it in the knee for sure.
DR. CIFU: Yeah, absolutely.
DR. STERN: Okay, let's go into some common misconceptions, why don't you start us off?
DR. CIFU: Okay, so this is good maybe to follow up with your last point, is that I think a misconception is that if you have a patient who comes in with back pain, sciatica, and you have an abnormal neuro exam, that that demands an MRI, okay? It doesn't because you're going to have people who maybe have a little bit of weakness that you have trouble getting out, or maybe a dropped reflex, but that's not something that someone's going to go to surgery for, right? And those people are going to, most of them are going to improve, they're going to be fine and you're going to be done.
DR. CIFU: Obviously, if someone comes in and they're like, have cauda equina syndrome where they've got gross motor weakness and they're tripping because of their foot drop, that person needs surgery and so that person needs to be imaged, but really subtle neurological findings in a setting of sciatica just helps you to say, I know you've got a disc herniation or I know you've got an osteophyte pushing on a nerve and we're still going to do conservative therapy.
DR. CIFU: We'll just follow you real closely.
DR. STERN: Right. The only thing I'd add to that is when you're saying weakness, you're really talking about weakness primarily in the foot or ankle. The nerve roots that go to the knee extension and the hip flexors are typically multiple nerve roots, and so the hip flexion and knee extension shouldn't be weak.
DR. CIFU: That's a good point.
DR. STERN: Right? And so if you see that, you need to think about something more complex.
DR. CIFU: Right, because it's pretty much impossible to get detectable weakness by knocking off-- L3 itself partially knocking off.
DR. STERN: Right.
DR. CIFU: Good point.
DR. STERN: So mine is that plain films-- the misconception is that plain films can rule out spinal mets and indeed they can't. You don't tend to see lytic lesions until 50% of the trabecular bone is lost and the sensitivity of the plain films is only 60%. So I think, I'm sure had she not gotten better, your next test of choice would have been an MRI for sure.
DR. CIFU: Right, no question about that, and it's funny because I think nobody hesitates to reach for the spine films with suspicion, but it's just so important to remember that if those are negative and things don't get better, you need to look harder.
DR. STERN: Do you happen to know what the sensitivity is for compression fracture of plain films?
DR. CIFU: I don't. I imagine it's very high, but I don't.
DR. STERN: Okay, your last misconception.
DR. CIFU: So my last misconception and anybody who's ever talked to me about medical reversal or medical evidence will know this one, the misconception is that vertebroplasty is effective. Vertebroplasty was very hot in the early 2000s and really into the 2000-teens as treatment for compression fractures because compression fractures are common. About a third of the time, they're incredibly painful and vertebroplasty which is going in and injecting medical cement into that compressed vertebrae makes such good sense that it should help, but in two beautiful though small studies in the New England Journal of Medicine, where vertebroplasty was compared to actually sham vertebroplasty, it was very clear that it has no effect, and as we've studied it over and over with time, if there is an effect, it is a small tangent effect and not worth the intervention.
DR. STERN: Didn't you write a book, Ending Medical Reversals?
DR. CIFU: I did once upon a time.
DR. STERN: I thought so, and was this in there?
DR. CIFU: This was in there.
DR. STERN: It's shocking. Well, that's great. All right, so let's turn to pet peeves.
DR. CIFU: My first is one that we've, I think, sort of already said. It's just that assuming that all back pain is benign. Most back pain is benign. If you assume it's all benign, you're going to be right most of the time, but you're not going to be right all the time and so you really have to take every back pain that you see seriously, especially when it's new and say, "Could this be something bad? Let me work this up." And if you decide that it's benign and you're not going to work it up, keep an eye on that patient.
DR. CIFU: So if they're not following the course of improvement that you expect, double back and take a look.
DR. STERN: So mine's the opposite of that. [both doctors chuckle] So mine is, we rarely have pet peeves vis-a-vis patients, but I'm a little scared to say this one, but I do see an inordinate number of patients where they assume that they must have an MRI for their back pain, and I spend a fair amount of time explaining to the patient, so there was a study years and years ago, that looked at MRIs of backs on patients who didn't have any complaints and found that a significant number, I think a third, had what might have looked like minor herniated disc, and so the decision, particularly in patients who have sciatica or non-specific back pain to get an MRI is fraught with problems because most patients with even radicular back pain and sciatica get better with medical therapy and if you're going to treat them with medical therapy, why do an MRI?
DR. STERN: So unless there's the alarm signs that we've been talking about, I think the appropriate course of action is usually, treat the patients, see if they get better, I mean, examine them, do a good history, do a good physical, and if they're not getting better, have a low threshold for imaging.
DR. CIFU: Perfect points, right? There's a lot of effort and understanding that we do too many X-rays. The downside of X-rays is mostly cost. There is actually an old study also, which looked at people who got X-rays and didn't get X-rays and it actually showed that the people who got X-rays took longer for their pain to get better, which is interesting.
DR. STERN: That's interesting.
DR. CIFU: Probably just because it's like, labeled them as more severe in their heads. MRI, there's the cost issue, but there's also the issue that you usually find something.
DR. STERN: Right, and they're getting more procedures.
DR. CIFU: Right.
DR. STERN: This might be the only time in the entire series of podcasts where I advocate doing less testing. Maybe in all the time you've ever known me.
DR. CIFU: But you always blame the patients for their problems.
DR. STERN: I do not. That's so not true. All right, let's go on to clinical pearls.
DR. CIFU: Okay. My first, this is no secret, it's well endorsed by the ACP, for non-specific back pain when people first come in, NSAIDs and heat work well up front, tell people to get back to their activity as tolerated, they should not in a million years be on bedrest. They should do what they can do and then daily exercises to sort of prevent this in the future. You may have them pick up a back pain exercise book.
DR. CIFU: You may have them have a couple of episodes with physical therapy because unfortunately, most people as they get into their 50s, 60s, they should be doing some exercise every day to keep their core strong and keep them from getting back pain later on.
DR. STERN: Sorry, did you mean that the exercise should be picking up the back pain book, or did you mean they should pick up a back pain book and read it?
DR. CIFU: Most of the back pain books are very light, I don't think it would help.
DR. STERN: And you know, it's funny you say that about keeping people moving. I had an experience probably 30 years ago. The natural tendencies when you have back pain is to stop moving because it hurts when you move, right? You have spasm, and so I had back pain and I was laying on the sofa in a lot of pain and I had to catch a flight and was late and I had to run at the airport to catch the flight and as I'm running, I'm thinking to myself, "I'm going to die when I get to the plane." I was just sure I was, and I got to the plane and I was like, wow, it's better because it stretched it out.
DR. STERN: Wow, that is crazy. All right, so my clinical pearl, I think we've mentioned, but I'll emphasize it is you do have to be wary of back pain in patients who've had bacteremia who are in the hospital and they're sick for some reason because they can actually seed that back, and it might not have been why they came in, but spinal abscesses or vertebral osteomyelitis can lead to paralysis, and you have very little time when this is going on to sort this out and get them into surgery before they have catastrophic outcomes, so important to remember.
DR. CIFU: Staphylococcus anywhere near the spine is a bad thing.
DR. STERN: Yeah, it's not what you want, or in the blood.
DR. CIFU: My last one is I guess, about spinal stenosis, and this will sound a little bit like what I think I said about migraines, that you should really work on kind of building your instance script for spinal stenosis. Sit down, talk to people, get a sense of what they're feeling, because spinal stenosis, yeah, sometimes it's classic neurogenic claudication, where the person tells you, "I walk and you know, I get pain going down my legs and I stop, but it doesn't go away until I sit down or hang over," but often it's very subtle, it's not as stereotypic and it may be hard to pick up but as you talk to people, you really get a sense for what spinal stenosis sounds like and you just got to do the work, talking to patients.
DR. CIFU: Another important point is a very diagnostic sign for spinal stenosis is a wide-based gait. So if someone comes in with back pain and a wide-based gait, that's got a likelihood ratio of 13 for spinal stenosis, but you know what? You're not going to notice that until you walk with the patient. So good idea, you're in there with the patient, you're doing their exam, maybe you have them do their heel walk and toe walk and then just go out in the hall, have them walk up and down the hall or even if you don't do that, if you're in a rush, they have to leave your office to go to the waiting room.
DR. CIFU: Just stand behind them and watch as they walk out. Sometimes you got to call them back and say, you know what? I just have another piece of information. And here's a pitch. Shameless self-promotion, you ready for this?
DR. STERN: I'm ready.
DR. CIFU: I want someday this to be called the Cifu sign is that if a patient ever just on their own comes in with back pain and on their own mentions a shopping cart, I think that is highly diagnostic.
DR. STERN: And you want it to be named after you?
DR. CIFU: I do, I do, the Cifu sign.
DR. STERN: [laughs] That's pretty shameless. I want to emphasize one thing you said before we stop, which is pseudoclaudication versus claudication, because I think it creates a fair amount of confusion. So in claudication, which is due to vascular insufficiency, patients often complain of pain in their legs, usually the calves, which gets better when they stop and they don't typically have to do anything else, they don't typically have to sit and they don't typically have to bend over, it just gets better when they stop, versus in pseudoclaudication from spinal stenosis, they also get pain that goes down their legs when they're walking and the difference is one, they're often not a vascular path, two, they do mention that if they bend forward, it gets better, and three, stopping alone might not make it better, like you said, they might have to sit, and so those are often confused and I think it was just worth bringing that out.
DR. CIFU: Totally, and both of them also remember, can be unilateral or bilateral.
DR. STERN: Right.
DR. CIFU: I think usually vascular is going to be unilateral first, but still, I've certainly seen both being either.
DR. STERN: And you can normally sort this out in the room, a combination of checking peripheral pulses and the exam and a good history shouldn't usually leave you confused about this.
DR. CIFU: Absolutely. We hope you found this episode of the Symptom to Diagnosis podcast useful and a bit enjoyable. A reminder that the cases that we discuss are drawn from our clinical experiences but, because protecting patient privacy is part of our oath, we never discuss actual patients and most cases are composites. As a reminder, our textbook, "Symptom to Diagnosis: An Evidence-Based Guide" takes a much deeper dive into how we think about and reason through the diagnosis of medical presentations.
DR. CIFU: The book is available in print, on your handheld device, And in a new fully searchable mode via the Access Medicine website available worldwide from McGraw Hill. The music for this, the S2D Podcast is courtesy of Dr. Maylyn Martinez.