Yes. Reflex sympathetic dystrophy, or RSD, is the older name for complex regional pain syndrome (CRPS). Today RSD maps to CRPS type 1, which NORD says makes up about 90 percent of cases. If your records use both words, nobody missed anything. You have one diagnosis in two vocabularies.
If you’ve just been handed a diagnosis, you may be reading two sets of words that look like two different problems. One page says RSD. Another says CRPS. A relative remembers a neighbor with "causalgia." It’s reasonable to wonder whether someone has missed something.
Those labels are simply what you’ll meet in your chart, on an insurance form and in a search box at two in the morning. If you want the full picture of the condition itself, we’ve already written Everything to Know About Complex Regional Pain Syndrome (CRPS).
I want to be very honest with you about one thing. A new name on your paperwork doesn’t change what you’re feeling. Your symptoms are real, and they make sense when we look at the nervous system.
Is reflex sympathetic dystrophy the same thing as CRPS?
Yes. RSD is the older name, and today it maps to one form of CRPS. The New York State Department of Health puts it this way: "RSD is an older term used to describe one form of Complex Regional Pain Syndrome (CRPS)."
The National Institute of Neurological Disorders and Stroke says the same thing from the other direction. It states that "CRPS used to be known as reflex sympathetic dystrophy (RSD) and causalgia." MedlinePlus lists "Causalgia, CRPS, Reflex sympathetic dystrophy" as names for the same health topic.
So if your doctor wrote RSD in 2012 and CRPS this year, you have the same diagnosis in different words.
What is the difference between RSD and CRPS type 1 and type 2?
RSD is the old name for type 1, and causalgia is the old name for type 2. What separates the two types is whether a nerve injury is involved.
The New York State Department of Health explains that "RSD is sometimes called Type I CRPS, which is triggered by tissue injury where there is no underlying nerve injury, while Type II CRPS refers to cases where a high-velocity impact (such as a bullet wound) occurred at the site and is clearly associated with nerve injury." NORD adds that "CRPS type I is also known as “reflex sympathetic dystrophy,” and it comprises about 90 percent of all cases of CRPS."
That’s why most people who were told they have RSD, or who read about RSD online, are really reading about type 1. It also explains why the older word hangs around so long.
Here’s how the old and new names line up, according to the public health sources we checked.
| Older name you may see | Where it sits today | Source |
|---|---|---|
| Reflex sympathetic dystrophy (RSD) | CRPS type 1 | NORD |
| Reflex sympathetic dystrophy syndrome (RSDS) | Same syndrome, listed as a common name alongside CRPS | Stanford Health Care |
| Causalgia | CRPS type 2 | New York State Department of Health |
| Sudeck’s atrophy, post traumatic dystrophy, shoulder hands syndrome, reflex neurovascular dystrophy | Other past names for the syndrome | Stanford Health Care |
Stanford notes that "In the past, this syndrome has also been called causalgia, Sudeck’s atrophy, post traumatic dystrophy, shoulder hands syndrome and reflex neurovascular dystrophy." If a family member’s old paperwork uses one of those, you’re looking at the same family of conditions.
Why did doctors stop calling it reflex sympathetic dystrophy?
The sources we checked don’t give one reason for the change, but they do show that the old name was built around an explanation that isn’t settled. "Sympathetic" points at the sympathetic nervous system, the part of your autonomic system that speeds you up when you’re frightened. Think of it as your body’s smoke alarm. It’s built to ring when something frightening happens, then go quiet again. Stanford explains that these pain syndromes "occur when the sympathetic nervous system goes awry."
The New York State Department of Health adds a caution in the same breath. It says the condition "is thought to be a malfunctioning of the sympathetic nervous system, but some researchers are questioning this." So the sources don’t fully agree on how much weight that one alarm should carry.
The cause itself is still open. MedlinePlus says plainly, "The cause of CRPS is unknown." CRPS describes what a person has, and it says less about why.
The sources do show a shift in how the types are sorted. The NINDS notes that "Historically, people were classified as having CRPS-I (previously called RSD) when there was uncertainty about the exact nerve injured." Today the sorting question is whether there is evidence of a nerve injury.
Why do some pages still say RSD and describe three stages?
Some public pages still use the old name, and some still walk through stages.
The Delaware Division of Public Health page still walks through stages. It says, "Stage 3 involves limited movement in limb because of tightened muscles and tendons (contracture), muscle wasting, and pain in the entire limb." If you’re newly diagnosed, reading that can be frightening, as though a countdown has started.
The Mayo Clinic describes the course differently. It says, "In some people, signs and symptoms of CRPS go away on their own. In others, signs and symptoms may persist for months to years." Progress looks different from one person to the next, and a fixed stage chart can’t tell you where you’ll land.
So when you see a page that lays out fixed stages, treat it as one description and keep in mind that Mayo says the course varies. Ask your own clinician what applies to you before you decide what your timeline looks like. Our piece on CRPS Awareness Month talks about why so many people are still piecing this together from scattered sources.
How is it diagnosed now, and does the name affect it?
The name on the page doesn’t change how a diagnosis is made. What matters is whether your symptoms and exam findings meet the current criteria. NORD describes the Budapest criteria, which look for symptoms in "at least 3 of the 4 following categories: sensory (increased in sensitivity), vasomotor (temperature or color changes in the skin of affected limb), sudomotor/edema (sweating changes or swelling) and motor/trophic (motor impairment or changes in the hair/nails/skin)."
The clinician then has to see it too. NORD says the patient "must also exhibit signs, which are observable by the health care provider, in at least 2 of the 4 categories above." It adds that "The Budapest criteria have recently been incorporated into the new ICD-11 international diagnostic coding system."
That’s why a chart that says RSD from years ago and a chart that says CRPS today can both be valid. They may simply have been written under different habits. If you want to know which criteria your own diagnosis rests on, ask the clinician who made it. It’s a fair question.
What should you check when your records use the old name?
Start by remembering that RSD maps to CRPS type 1 and causalgia maps to type 2, then see which of those words your records use. Then look at the date on the record. A note from many years ago may use RSD where a current one would say CRPS type 1.
If you’re gathering records for a new provider, copy the exact terms rather than translating them. A receiving clinic can read "RSD" and "CRPS" as the same thing, and your original wording is part of your history.
Early attention matters as well. The Mayo Clinic notes that "Treatment is likely to be most effective when started early in the course of the illness." That’s a reason to get a clear diagnosis soon. Where you go for care can wait until you’ve asked your questions.
When you’re ready to think about the nervous system more broadly, our post on Healing Neurological Dysfunction is a calm place to start.
Common mistakes with the old name
The most common one is assuming RSD is a milder or earlier version of CRPS. RSD is an older word for type 1, and type 1 is the larger group.
A second mistake is taking a page’s stage description as your forecast. A stage list on a public page is one description, and the Mayo Clinic says the course varies from person to person. Your clinician knows your presentation. A health department page written for the general public doesn’t.
Third, people sometimes decide their diagnosis must be wrong because two documents disagree on the name. Check the dates first. Labels that disagree often just come from different eras.
And some people stop reading because the vocabulary feels like it’s running ahead of them. If that’s you, it’s normal. You don’t have to learn the history of a name in a week to get good care, and healing takes the time it takes.
FAQ
Is RSD the same as CRPS?
Yes. RSD is the older name, and it now corresponds to CRPS type 1. The New York State Department of Health calls it "an older term used to describe one form" of CRPS. MedlinePlus says CRPS causes intense pain, "usually in the arms, hands, legs, or feet."
Is reflex sympathetic dystrophy still a diagnosis?
Doctors mostly use CRPS now, but RSD still appears in older records, books and many public health pages. If your chart says RSD, ask which CRPS type it corresponds to and which criteria were used. The condition is the same, even where the label differs.
What was causalgia?
Causalgia is the older name for CRPS type 2, the type clearly associated with nerve injury. The New York State Department of Health says Type II used to be called causalgia. If you see it in an old record, ask a clinician how it maps to current terms.
Does the name change what treatment I need?
No, the name alone doesn’t set treatment. A clinician decides based on your symptoms, your exam and your history. MedlinePlus says treatment "focuses on relieving the pain, and can include medicines, physical therapy, and nerve blocks." Ask your own doctor what fits your case.
One step you can take today
Pull out the oldest and newest documents you have about your diagnosis and write down the exact words each one uses. If you’d like a second set of eyes on them, schedule a free discovery call with The Spero Clinic. Bring that list, and we’ll listen to the full picture and tell you honestly whether Spero is a fit.
