This is the talk you've been waiting for. This is why you became hand surgeons. So we're going to talk about complex regional pain syndrome. So complex regional pain syndrome has historically been known by multiple terms, reflex sympathetic dystrophy, shoulder hand syndrome, among others. But actually, the conference in 1994 at the International Association for the Study of Pain, which I bet was a great conference to be at, came up with the current terminology, which was CRPS. As Robert Strauch always calls this, this is CRAPS. And that's how you feel when you diagnose it and see it in your patients. So CRPS, though, is divided into three types. And this is really simple. We just have to get it down. So type 1 is CRPS without an identifiable nerve lesion. Type 2 is CRPS with a specific nerve injury or compression. And then type 3 are those other pain syndromes, including fibromyalgia. I am not going to talk about that today. Yeah, thank you. 1 and 2 is enough. You guys are just getting nauseated and leave. OK, so type 2, that with a nerve lesion, is a clinical diagnosis. It may be supported by nerve conduction testing, but it's a clinical diagnosis. And then realize that that type 1 and 2, either one of them can be either sympathetically mediated or sympathetically independent. So the diagnosis for CRPS, they came up with four criteria. The last three need to be present. So number one, there's usually some sort of noxious event. Number two, I think we all recognize you need this continued disproportionate pain. Number three, you'll see some changes, usually sympathetic-related edema, skin blood flow, temperature, sweating changes. And then number four is the key as well, that there is no other explaining diagnosis. This is a diagnosis of exclusion. There is no definitive test for CRPS. So it's on us to make sure nothing else will explain this ongoing pain. So understanding briefly about pain physiology, pain travels up to your brain with the small myelinated and unmyelinated nerve fibers, the A delta and the C fibers. It's modulated along the way. And then there's also modulation decreasing those pain experience coming from the brain down. So CRPS has been either caused by or is associated with changes at all levels of the nervous system, all the way from the cutaneous nerve fibers up to changes in the central nervous system. So just realize it's an entire myriad of changes that really produce this. Now it's been associated with different mental comorbidities or mental health. Anxiety before total knee arthroplasty has predicted CRPS. Multiple allergies or hypersensitivities also associated, as well as longer duration of anesthesia. But just realize that CRPS is not entirely a mental problem. It is not just depression or some other kind of thing that's just in the brain. There's more going on. Now realize that depression will overlap with this a lot, but as you can expect, it's kind of a chicken and the egg because if you've got chronic pain, a lot of you are gonna be depressed. And by the same token, if you treat the pain, a lot of times the mood improves. So just realize these things are related, but they're not just caused by depression or other mental illnesses. Now in terms of the incidence and demographics, there was a classic study that gets quoted on every test. This is that study by Minnesota and Olmstead County that found the incidence of about five per 100,000 person years. Thankfully, it's not more. And the prevalence is about four times that. We know this is a disease usually of middle-aged adults. It's more in women. It's more in the upper extremity. And it is exceptionally highly frequent after distal radius fracture. So next is the graph just showing the peak in incidence there in that kind of middle adult age range. So why distal radius fractures? You know, why us as hand surgeons? I think the problem gets back to type two disease because that's what we're typically gonna see. And if you look at some of the classic literature by Gelberman in the 1980s, you look at patients with distal radius fractures, we know they swell. And if you document the pressures in the carpal tunnel, they quickly get up into the 40 millimeters of mercury. You're gonna create nerve problems and then lead to CRPS in addition to carpal tunnel syndrome. It was also accentuated by wrist flexion. The classic reduce the distal radius and overflex the wrist. And to this point, one of the later papers has demonstrated that the vast majority of CRPS after distal radius fracture is in fact type two disease. Usually carpal tunnel, sometimes ulnar nerve as well. So the disease happens and lasts for a while. The mean duration of pain's about three years and almost a third of patients are out of work for at least a year. And that's why when we saw the numbers with the incidence, the prevalence was much higher because it lasts for a long time and it doesn't kill you. Okay, staging. On the test, I do not think there will be any questions about staging. I present this to be thorough because there's a lot of disagreement here. The classic staging was acute dystrophic and atrophic but subsequent studies have really shown there's not a true time course here that's predictable between these. Andy Komen likes to talk about hot versus cold CRPS and then there's another group of people that say nope, when you're into, anytime you're into atrophic or cold CRPS, it's not really CRPS anymore. In the same way that somebody with Volkman's contracture doesn't still have compartment syndrome, it's really a sequela. So how do we recognize them? I think everyone in this room probably recognizes the CRPS patient when you walk in the room. They've got the glasses, they don't want you to touch their hand, they're pulling it back very protective and they tell you that everything hurts. They're not comfortable, the air hurts, any little stimulation causes pain. And again, for diagnostic testing other than looking at the patient, there is no single test. However, if they ask you on a multiple choice test, what are the particular findings that you expect? On an x-ray, you're looking for periarticular demineralization. On a triple phase bone scan, you're looking for increased periarticular activity in the third phase. Now I've quoted some sensitivities and specificities there. Basically it ranges depending on the study. And then there are other tests that you can do kind of looking at the autonomic function or dysfunction in the area. So here's just one x-ray showing a lot of resorption of the bone around the joints after just a radius fracture in a patient with CRPS. Determining if it's sympathetically mediated, typically you need to do a saliganglion block. And in life and on a test, to truly say whether or not it's related, you have to have that block produce some sympathetic changes, such as a Horner syndrome. So that if you know the block was effective, now you can decide if the pain actually changed to determine whether or not it's sympathetically mediated or not. Okay, treatment. So treatment's not easy. That's why treatments one, two, and three are prevention. So we avoid tight casts, we try not to hurt causalgic nerves, such as the palmar cutaneous branch of the median nerve or the superficial branches of the radial nerve. And then there's a question mark next to vitamin C. Vitamin C's been quoted as kind of our one preventative drug for this, but I'll show you some of the evidence and why I'm not so sure the answer's so clear on maybe this upcoming test for you. So when the AAOS made guidelines about treating distal radius fractures, if you read them, as like any guidelines, there's very few things with evidence. But one of the few points they made with moderate level evidence was that you should give vitamin C for prevention of disproportionate pain or CRPS. Now that statement was based on research like this. And so vitamin C has an antioxidant quality and it can actually decrease blood and fluid leaking from capillaries. So it actually does have some basis in physiology and why it might work. So here's a large study, JBJS. They did a randomized trial, 400 patients, and they markedly decreased the incidence of CRPS by giving vitamin C. And this study came up with the dosage, which I think is most widely referenced, which is 500 milligrams for 50 days. It's simple for orthopedists to remember because we've just got easy numbers, 550, but that's what they recommended. Here's another study, very similar, only foot and ankle fractures. And again, giving vitamin C dropped the CRPS incidence from about 10% to 2%. Now most of the detractors are the people that don't buy this literature. The question that comes up is, well, how did you have a 10% incidence in people untreated? That seems high. And in all these studies, the critique is always, well, how did you really define CRPS? How severe was it before you called it? And so that's sort of the questions that come up. But the bigger question in terms of test taking and the efficacy of vitamin C, I think has been raised by this study, which was a big one just two years ago in JBJS, where it was now an independent group that had not studied CRPS before, and they did distal radius fractures over 300 patients. And in giving that recommended amount of vitamin C, they found no effect at a year, no effect of patient-reported disability on the DASH, no effect on the incidence of CRPS, and no change in fracture healing. So I think the jury is out. I'm not sure if we know for sure if vitamin C does a lot, but I don't think it can hurt. So what do you do as the hand surgeon? Number one, you want to make the diagnosis so the person can get treatment, and number two, you want to identify type 2 disease because that's where us as the hand surgeons can make a difference for the patient. So treatment, it's kind of a multi-team approach, OT, PT, sometimes people get nerve stimulations, nerve blocks, different medications. I don't believe any of these are FDA approved, but it's the typical run of antidepressants, anticonvulsants, bisphosphonates, steroids, among others. So you want a whole team. I think in part because it will wear you out if you try to manage these people by yourself. But really, it does take a whole group of people to try to get this pain better. So what are the outcomes? We know they're not perfect, but if you treat it early, you see here on the top line, within four months of the symptom starting, about 90% of people ended up in the good category, which is pretty nice, not perfect, but good. And then if you have people that are untreated or not diagnosed for a year before you start trying to treat this, I think permanent changes have happened in the nervous system, and you see about 50% of people continuing to have permanent impairments, so early treatment counts. And then if you look at digit contractures with distal radius fractures, we want to treat that early because if it's persistent at multiple months, it's gonna predict long-term problems even many years down the road. So nerve decompression, does it work for type 2 disease? I would say absolutely yes. Based on the evidence, and I can say based on my practice, I would agree as well. So the first study here in 2005, just a small study, eight patients. When they went in and did the carpal tunnels later, you found much less swelling, much less hypersensitivity, and function improved and pain results went down. And then it's also echoed in another older study where they had, actually this was pretty impressive, 26 of 29 patients with improved swelling. And this PIP motion thing, I think is really legitimate. I wondered about it when I started practice. You know, people have the distal radius, they can't bend the fingers, they hurt. When you do the carpal tunnel release, the PIP motion actually really does get better. Not perfect, but it improves quite a bit. And then what about amputation? Because this comes up as well. Sometimes these people get kind of at the end of their rope and they say, just cut it off. Well, there's been several very good studies, I would reference these two. The first on the top noted an 82% recurrence rate after amputation. So just cutting off the painful part does not ensure that you will not have pain coming back. And then this other study in 2011 really looked at amputations over 100 with almost 40 in the upper extremity. And what they found was a bit sobering because even with amputation, very few people used a prosthetic. Almost half had recurrence of pain. And then very few, 13 out of 43, returned to paid employment. So you have to understand that amputation can be used in dire circumstances. There are certainly people here in these series who benefited, but a lot of people didn't and had persistent problems. So it's not a easy answer. And then finally, if you have to operate on somebody after they've had CRPS, there's evidence that doing some sort of perioperative or preoperative stellaganglion block will actually help reduce the chance that you then develop CRPS related to your subsequent procedure. So in summary, this is really the result of a complex interaction. A lot of interrelated factors with the nervous system. It's gonna impart marks and pretty prolonged morbidity a lot of the times. Vitamin C may be effective. I don't know, the jury's out, but it may be effective in prevention. Not treatment, but possibly prevention. And then the early treatment optimizes outcome. And then type two disease, when you recognize it, don't be afraid to just go ahead and proceed and decompress those nerves. Don't wait, because waiting, it just sort of continues the process. Two short questions. Before the last couple of years, before that last study in 2014, the question on the test was always this. If you give vitamin C, what does it do? It either prevents CRPS or the question was, what was the dose? And remember, we're very simple surgeons. The only numbers we can remember if they're all symmetric. So the answer is to give 500 milligrams for 50 days. And then this question came up in 2014. Otherwise, there's not a lot of questions on CRPS. This asked about laser Doppler imaging and cold stress testing. And what was it useful for? So think about cold stress. Is it specific for the diagnosis? I've already told you nothing is perfect for the diagnosis. Do they eliminate the need for blocks? Nope, these things are used for diagnosing. High flow states don't respond? Nope, there's nothing with that. But do they provide an assessment of distal autonomic function? Yes, because they're assessing your response to a cold or a stress. And then the studies are more reliable than clinical diagnosis? No. And so I'm almost done. I'll give you one case since we're a couple minutes ahead. But basically, here's an older person with a distal radius fracture. She comes in, pain, stiffness, swelling. You see a dash score that's all fours and fives. Here's the hand, it's swollen. It's more swollen than the other side. Can't make a fist. Key points, two points off. They're hypersensitive. The question is, do you do nerve testing? You can, there was findings. What do you do? Go ahead and proceed with the carpal tunnel release. All right, thank you guys.

complex regional pain syndrome

CRPS

diagnosis criteria

treatment options

early treatment