Understanding CRPS/RSD – As Taken from Fitness for Your Health

Written By Michael Sullivan, PT, MSPT for RSDSA blog.

This post is about understanding CRPS was originally featured on “Fitness for Your Health.” Learn about the pain and how they diagnosis it here.

This week’s topic is one not many know too much about but it can be a very debilitating condition. Those who suffer from Complex Regional Pain Syndrome (CRPS), A.K.A. Reflex Sympathetic Dystrophy (RSD), know far too well how bad this condition is. It is a very complex condition (hence the name), so we have asked the Director of Physical Therapy here at our clinic to explain it.

Michael Sullivan earned his MSPT at Duke University in 1989. He worked in private practice for eight years before deciding to move to help those suffering from chronic pain in a multidisciplinary setting. He joined BAPWC in 2011 and continued to spread his knowledge. He went so far to train a Labradoodle named Seamus to become the clinic’s therapy dog! While his head is like a library of physical therapy, a benefit the clinic staff have all been privy to is his ability to BBQ. The man can cook over an open flame!

Those suffering from CRPS/RSD and those who have never heard of the condition can benefit from this post. CRPS is one of those diseases that sometimes cannot be seen, but those suffering from it can never ignore it. If you have questions or comments, please fill out the form at the end of the post and we will get back to you within 24 hours!

De-mystifing the diagnosing of Complex Regional Pain Syndromes (CRPS)

If you or someone you know has been diagnosed with CRPS and you are better trying to understand what that means, whatever you do, do not search the internet for images of CRPS. Now that I told you not to do that, you are curious and you are thinking, ‘maybe I’ll have just a quick look’. DON’T DO IT! There is way too much of the ‘Worst ______________ Ever!’ phenomena going on out there. Go ahead and fill in the blank with just about anything and do an internet search. Plug in ‘sunburn’ or ‘mosquito bite’. It is enough to have you afraid to go outside in a December blizzard in Chicago without slathering on SPF 120 sunscreen and pure DEET.

Over and over we meet and evaluate people who are looking to better understand this diagnosis and what to do about it. I would like to share with you today information about how the diagnosis is made. By the time many patients get to us they have often been through a myriad of tests and a handful of specialists. Some are misdiagnosed, while others are told that there is nothing wrong with them and that ‘it’s all in your head.’ And while technically, there is a great deal going on with the brain in CRPS, this is not always the intent of the message that is being delivered. CRPS is not a psychological disease, but it is a disease that creates changes in our central and peripheral nervous system, including our brain.

Why is there so much confusion around this diagnosis? One reason is that there is no one test that can be run as definitive proof of the presence or absence of a complex regional pain syndrome. I have seen a CRPS claim denied because the insurance adjuster thought that an unremarkable MRI was proof that nothing was wrong with the patient. Another reason is that the criteria for accurate diagnosis has changed as recently as 2003, with the model being validated in 2010. There is a lot of confusion out there amongst the medical community and the insurance industry that can lead to unfortunate outcomes as improper diagnosis leads to an incorrect treatment plan and often times long delays in receiving appropriate care. Lastly, there is still a lot that we don’t know about the pathophysiology or underlying cause of CRPS.

The gold standard right now for diagnosing CRPS came from a meeting of experts in Budapest in 2003 and is called the Budapest Criteria. Further study attests to the accuracy of using these criteria and this is what your health care professional should be referencing to diagnose CRPS. The diagnosis requires some good old fashioned evaluation skills; talking to our patients to understand their symptoms and evaluating them for the appropriate diagnostic signs. An excerpt from Harden et al. (1) puts forward the following criteria for diagnosing CRPS:

  1. Continuing pain, which is disproportionate to any inciting event
  2. Must report at least one symptom in three of the four following categories:
    1. Sensory: reports of hyperesthesia and/or allodynia
    2. Vasomotor: reports of temperature asymmetry and/or skin color asymmetry
    3. Sudomotor/edema: reports of edema and/or sweating changes and/or sweating asymmetry
    4. Motor/trophic: reports of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
  3. Must display at least one sign at time of evaluation in two or more of the following categories:
    1. Sensory: evidence of hyperalgesia (to pinprick) and/or allodynia (to light touch and/or deep somatic pressure and/or joint movement)
    2. Vasomotor: evidence of temperature asymmetry and/or skin color changes and/or asymmetry
    3. Sudomotor/edema: evidence of edema and/or sweating changes and/or sweating asymmetry
    4. Motor/trophic: evidence of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
  4. There is no other diagnosis that better explains the signs and symptoms

Let’s take a closer look at each of these criteria to better understand them.

Continuing pain, which is disproportionate to any inciting event.

Often times a very minor injury can result in severe signs and symptoms. The belief that there has to be a significant injury to result in CRPS is not accurate. I’ve seen minor ankle sprains, small contusions, and small puncture wounds trigger a complex regional pain syndrome that is just as involved as a person who was run over by a forklift. Immobilization following an injury can be the precipitating factor. Immobilization of even a healthy limb can result in CRPS. Unfortunately, this can provoke skepticism in those not skilled in making this diagnosis, and can lead to delayed care as the nature of the injury is viewed as minor, while the consequences can be quite profound.

What are those consequences you ask?

Must report at least one symptom in three of the four following categories:

  • Sensory: reports of hyperesthesia and/or allodynia.  Hyperesthesia is increased pain with a painful stimulus such that a simple prick with a pin can be a significant pain generator.  Allodynia is pain with non-painful stimuli.  Some people get tactile allodynia where even light touch can provoke pain; they cannot have a sheet resting on their affected extremity at night or the wind blowing on the affected extremity can be severely painful.  In some cases near contact or imagining contact can trigger a pain response.  Others may get temperature allodynia where they cannot tolerate warm water in the shower.  Some do not tolerate movement, or deep pressure.  It is important to recognize that not all stimuli that are painful are harmful.  By definition, allodynia does not involve any tissue damage, rather sensitization of the nervous system will send information (nociception) to the brain that is processed as pain.
  • Vasomotor: reports of temperature asymmetry and/or skin color changes and/or skin color asymmetry.  Patients will report that the affected extremity is to cold or hot to touch, the extremity can become mildly to severely discolored.
  • Sudomotor changes/edema: reports of edema and/or sweating changes and/or sweating asymmetry.  Hyperhydrosis, or excessive sweating is a common description to the point that people will describe one hand or foot dripping with sweat while the other is completely dry.  Edema, swelling in the soft tissue, may come and go without reason.
  • Motor/trophic: reports of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)  This is fairly self explanatory in the person’s experience and fairly complex to explain.  Motor changes occur due to changes in the brain that are referred to as neuroplastic changes.  Our brain is constantly changing in response to all that it processes including sensation, joint position, movement, smells, tastes, sights and sounds.  Changes in specific areas of the brain can result in diminished quality of movement affecting our ability to plan movement and execute movement.  Trophic changes can include thinning fragile skin, excessive hair growth, ridged nail growth or loss of hair and absence of nail growth.

As you can see, there are a very wide variety of symptoms experienced by the person with CRPS and they can change frequently.  This can be baffling to providers not accustomed to treating this disease.  These symptoms usually involve one limb and my experience is that most people can draw a line on the affected extremity indicating where their symptoms end or will describe symptoms diminishing as you move up the limb.  In approximately 7% of CRPS sufferers symptoms will spread to other body parts.

Must display at least one sign at time of evaluation in two or more of the following categories: This is the same list as above, but now the evaluating clinician has to observe at least one of these findings in two or more of the four categories in order to make a diagnosis.  As a frequent caregiver for people with this condition, I can tell you that many of these signs can change rapidly.  I could be looking at a normal colored limb, equal in temperature to the contralateral limb with no swelling and then have a stressful conversation with the patient and watch the affected limb change colors, get cold and sweaty.  Conversely other CRPS patients have more stable findings: a deep purple limb that is cold and damp to touch, allodynia with light touch that is well defined with swelling and a tremor when attempting to move.  If you have one of these limbs, your chances of being diagnosed are likely greater.  An evaluator doing a quick one time evaluation at the ‘wrong time’ may not see any of these signs and discount the diagnosis.  If symptoms are consistent with diagnosis, but signs are lacking a prolonged evaluation or repeat visit is recommended prior to coming to a conclusion.

  • Sensory: evidence of hyperalgesia (to pinprick) and/or allodynia (to light touch and/or deep somatic pressure and/or joint movement). Some people will be fine with light pressure, but not with deep pressure or the other way around.  Some will have no allodynia or hyperalgesia. Some will begin demonstrating distress if anyone nears their affected limb.  We always ask if it is OK to touch before we approach.
  • Vasomotor: evidence of temperature asymmetry and/or skin color changes and/or asymmetry.  We use an infrared thermometer to get hand or foot temperatures without triggering a pain response.  Any temperature differential between contralateral limbs greater that 2 degrees Fahrenheit is considered significant.
  • Sudomotor/edema: evidence of edema and/or sweating changes and/or sweating asymmetry: Lightly touching a palm or the sole of the foot to check for moisture changes is effective.  Swelling can be mild or severe and may be intermittent or constant.
  • Motor/trophic: evidence of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin): assessing active range of motion for joint restrictions also gives information about the quality of the movement.  Adding some resistance with strength testing when pressure is tolerated can reveal more motor control problems with exertion.  Some people will assume a fixed posture with the affected limb that and won’t tolerate any movement with increased muscle tone present (dystonia).  Trophic changes are easy to see when comparing an affected to a non-affected extremity.

There is no other diagnosis that better explains the signs and symptoms:  if the presence of known trauma or identified disease can explain the signs and symptoms then a CRPS diagnosis is not indicated.

Our patient experiences indicate that there is a need for increased awareness of CRPS in all facets of care delivery.  The lack of a stereotypical presentation is common, but sticking with the Budapest Criteria allows one to consistently make an accurate diagnosis, which is key for delivering effective therapies.  This is a very complex topic and my intention is to help educate people on the proper way to diagnose CRPS in a way that is easy to understand.  In the process of doing this I have glossed over many other aspects of the disease including pathophysiology, specific neuroplastic changes as a result of the disease, classifications of the disease and the types and rationale for treatment.  We can leave those for another time.

To those of you struggling with CRPS, our quality of care and knowledge increases every year thanks to a lot of good people doing research and administering compassionate care based on the science of this disease in particular and chronic pain in general.  There is help available.  I would like to recommend a couple of resources.  I don’t benefit in any way from recommending these resources, but appreciate the work being done.

For those of you who want to dive a little further into the Budapest Criteria previously mentioned see:

  1. Validation of proposed diagnostic criteria (the “Budapest Criteria”) for Complex Regional Pain Syndrome

Norman Harden,a,*Stephen Bruehl,bRoberto S.G.M. Perez,c,d Frank Birklein,e Johan Marinus,d,f Christian Maihofner,g Timothy Lubenow,h Asokumar Buvanendran,h Sean Mackey,i Joseph Graciosa,a Mila Mogilevski,aChristopher Ramsden,a Melissa Chont,b and  Jean-Jacques Vatinej

Pain. 2010 Aug; 150(2): 268–274. 

Published online 2010 May 20. doi:  10.1016/j.pain.2010.04.030

For those of you who would like to learn more about how acute and chronic pain differ I highly recommend the work of the Neuro Orthopaedic Institute and in particular the book Explain Pain.  It speaks to clinicians and patients alike.  David Butler and Lorimer Moseley are innovating care for CRPS based upon their findings.


I’m looking forward to reading their follow up to Explain Pain just out.

For a first hand account of a physician who has suffered with chronic pain and discusses how this has specifically influenced his care model while walking you through the maze of treatment options Dr. Peter Abaci’s books ‘Take Charge of Your Chronic Pain’ and ‘Conquer Your Chronic Pain’ are instructive and easy to read.  They can be found on Amazon.

Disclaimer: I read Dr. Abaci’s first book in 2011 while looking for like minded professionals to help treat chronic pain.  I have been working with him ever since.

For those of you looking for more CRPS specific resources The RSDSA has been on the forefront of CRPS research and advocacy for the past 30 years.  They can be found at rsds.org/

Pain. 2010 Aug; 150(2): 268–274. 

Published online 2010 May 20. doi:  10.1016/j.pain.2010.04.030

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