Complex regional pain syndrome (CRPS): early signs, treatment, and gentle, graded exercises

What CRPS is

CRPS is a painful condition in a limb, with changes in feeling, movement, the skin, sweating, swelling and bone. The pain is much more severe and lasts much longer than the injury would normally cause, and the skin can become so sensitive that a slight touch, a bump or even a change in temperature causes intense pain.

Other symptoms can include burning, stabbing or stinging pain; tingling or numbness; swelling and stiffness; skin that is hot and red at some times and cold, blue and sweaty at others; hair and nails that grow unusually fast or slowly; tremor or muscle spasms; difficulty moving the limb; poor sleep; and a limb that feels as if it doesn't belong to you, or feels bigger or smaller than it is. The bone can thin in patches, though the NHS says there's no evidence this leads to fractures. Older names include reflex sympathetic dystrophy (RSD) and Sudeck's atrophy.

Sources 1, 2, 3

Two types, and how it's classed now

Type 1, much the commoner, follows an injury without major nerve damage; type 2 follows damage to a major nerve. The UK guideline says the difference doesn't change how it's managed, except that a damaged nerve can sometimes be treated with surgery.

A 2021 international consensus kept the diagnostic criteria, added a subtype for people who once met them and still have pain, and placed CRPS among the chronic primary pain conditions, as the chronic pain guideline from NICE (the National Institute for Health and Care Excellence) does. A 2024 review calls CRPS a rare disorder that usually follows trauma to a limb, and says effective treatment remains a challenge.

Sources 1, 4, 5, 6, 7

It is real, and it isn't in your headEmerging evidence

The UK guideline says it is now clear that CRPS is not linked with psychological problems before the pain, or with somatisation or malingering, and that many patients still report not being believed. A review of 31 studies found that the prospective ones showed no link with depression, anxiety, neuroticism or anger, and in 596 people followed after a fracture, none of the psychological factors measured predicted who developed CRPS.

Fear and worry can make any pain worse, which is why psychological support is part of care, not a sign that the pain is imagined. The guideline also says that developing CRPS after an operation is not, in itself, evidence that the surgery was done badly.

Sources 1, 8, 9

Who gets itStrong evidence

It is uncommon. In a Dutch general practice database of 600,000 people, about 26 in every 100,000 developed it each year, women 3.4 times as often as men, most often aged 61 to 70; in Olmsted County in the USA the rate was about 5.5 in every 100,000 a year. In both, the arm was affected more often than the leg, and a broken bone was the trigger in 44% and 46%.

Most cases follow an injury, usually within a month: a fracture (a broken wrist above all), a sprain, a burn or a cut, an operation, or time in a cast. The size of the injury doesn't predict it, and about 1 in 10 people can't recall any injury. Children can get it too.

Sources 10, 11, 1, 12

How often it follows a fractureMixed evidence

It depends on how strictly CRPS is defined. In 596 people with a single fracture of the wrist, the scaphoid, the ankle or a foot bone, 7% met strict criteria, 21% a looser set and 48.5% the oldest, loosest criteria, and none of those with CRPS by the strict criteria was free of symptoms at a year.

After a wrist fracture treated without surgery, 3.8% of 1,549 people developed it within 4 months. In Denmark's national register, 0.2% of 247,128 wrist fractures led to a diagnosis within a year (0.31% after surgery, 0.17% without). The UK guideline says a short-lived, CRPS-like reaction is common after fractures and operations (1% to 25%), but CRPS lasting more than a few months affects fewer than 1 in 1,500 people.

Sources 13, 14, 15, 1

How it's diagnosed, and what tests can't showStrong evidence

By examination, using a checklist called the Budapest criteria, agreed at an international meeting in Budapest: continuing pain out of proportion to the injury; symptoms in at least three of four groups and signs in at least two (changes in feeling; colour or temperature; swelling or sweating; and movement, skin, hair or nails); and nothing else that explains it better. In a study of 160 people with nerve pain, the criteria picked up 99% of those with CRPS and correctly ruled it out in 68% of the others, much better than the older criteria.

No single test confirms it. Blood tests, X-rays, MRI (magnetic resonance imaging) scans and nerve tests rule out other causes; the UK guideline says bone scans aren't needed and can delay treatment, and the European standards say no test is needed except to exclude other diagnoses. It usually isn't diagnosed until 2 to 4 weeks after an injury, because early on the signs look much like normal healing.

Infection, a bone that hasn't healed, arthritis, a trapped nerve, poor circulation, a blood clot and other conditions can look like CRPS. As one NHS pain service puts it, the signs can mimic other conditions, so new pain after an injury needs examining rather than guessing.

Sources 16, 17, 1, 4, 18, 19, 20

The earliest warning signsEmerging evidence

The UK guideline lists a cast or dressing that is, or feels, too tight, and pain far worse than expected in the cast or when it comes off, as possible early warnings. In 1,549 people with a wrist fracture treated without surgery, an average pain score of 5 out of 10 or more in the first week was a strong warning sign, and that simple score predicted CRPS almost as well as a four-part assessment.

A limb that doesn't feel like yours is a feature of CRPS, but it can also happen after injuries without CRPS, so it's a reason to mention it to your team, not a diagnosis.

Sources 1, 14

How it usually goesMixed evidence

Most people improve. The NHS says about 85% slowly get less pain and fewer symptoms in the first 2 years. The UK guideline says pain eases completely or partly in up to 80%, often within 18 to 24 months and sometimes even after many years, while about 15% still have severe pain and difficulty using the limb at 2 years. In Olmsted County, 74% recovered, often without specific treatment.

But recovery is often incomplete. In 59 people followed from the start, symptoms improved most in the first 6 months, yet only 5.4% were free of symptoms at a year. A review of 22 studies found pain and movement problems still present in 51% to 89% after a year or more, with grip 25% to 66% weaker and 30% to 40% not back at work; in a Dutch group followed for nearly 6 years, 31% couldn't work. Stiffness and weakness are the most likely to last, and swelling and colour changes the most likely to settle.

True spread, meeting the full criteria in another limb, happens in about 7%; pain in other limbs without the other features is commoner and doesn't count as spread. Flares are normal, usually settle over days or a few weeks, and don't mean the condition is getting worse. Stress in particular can bring them on.

Sources 21, 1, 11, 22, 23, 24, 25, 26, 4, 3

The honest headline: no treatment is provenStrong evidence

A Cochrane overview of 17 systematic reviews found no high-certainty evidence for any CRPS treatment: the trials are small and mostly at high risk of bias. The Cochrane review of physiotherapy (34 trials, 1,339 people) rated every comparison very low certainty, but expects physiotherapy and rehabilitation to remain the first treatments.

The UK guideline's advice rests on expert consensus rather than graded evidence, and an appraisal of six CRPS guidelines found little guidance on how much exercise, how often, or how to progress it. So the plan on this page follows the guideline's approach. It isn't a proven formula.

Sources 27, 28, 1, 29

What every guideline agrees on: gentle, graded movement and useStrong evidence

The UK guideline asks for physiotherapy or occupational therapy to start as soon as CRPS is suspected, with gentle movement, light everyday use of the limb, attention to it and desensitisation, and it encourages early weight-bearing. Holding a joint still risks long-term stiffness, and mobilisation that strongly worsens pain is advised against. The European standards ask for generally gentle, graded exercises in the presence of pain, and for immobilisation to be avoided wherever possible.

The NHS adds that too much or too vigorous exercise can aggravate the condition, so therapy should be supported by a therapist with experience of CRPS, and that exercise can range from gentle stretches to exercise in water and weight-bearing. This is consensus: the trials behind it are very low certainty.

Sources 1, 19, 21

Who manages it, and when to ask for more helpStrong evidence

Care rests on four pillars of equal importance: education and self-management, physical rehabilitation, pain relief and psychological support. Mild CRPS can be managed by your GP with a physiotherapist or occupational therapist (a hand therapist for the arm, where available), and the NHS says people are usually referred to a specialist pain clinic as soon as possible.

The UK guideline asks therapists to refer on if there's no response within about 4 weeks, and the European standards ask for specialist referral if pain and function aren't clearly improving within 2 months. Spread to another limb, a hand or foot twisting into fixed positions, blisters or sores, swelling that can't be controlled, children, and CRPS that isn't settling after 6 to 12 months all need specialist care.

Sources 1, 21, 18, 19

Physiotherapy in early arm CRPS: one trialEmerging evidence

In 135 people with CRPS in one arm for less than a year, physiotherapy, and to a lesser degree occupational therapy, eased pain during and after effort and improved wrist and finger movement faster than social work support over the first 3 to 6 months, though the gains over the whole year didn't differ much. Cochrane rated it very low certainty and found a small improvement in impairment at 12 months.

Sources 30, 28

Graded motor imagery: promising, but not reliably repeatedMixed evidence

Graded motor imagery (GMI) has three stages of about 2 weeks each: recognising left and right hands or feet in pictures, imagining movements, then mirror therapy. In 13 people with long-standing CRPS after a wrist fracture, it reduced nerve-type pain much more than usual care. In 51 people with CRPS or phantom limb pain, pain fell by 23 points out of 100, against 11 with physiotherapy and usual care, and the gains held at 6 months. Pooling the CRPS patients in these two trials, Cochrane found about 14 points less pain out of 100.

But a shorter programme found no difference, a trial in CRPS after a nerve injury found no clear benefit and 12 of its 22 people reported more pain while training, and when two UK CRPS centres used it alongside other good care, average pain didn't improve (changes of 0.6 and 0.2 points out of 10), though left and right judgements did. One NHS hand therapy service doesn't use it for people with dyslexia or for children. Your therapist will say whether it suits you.

Sources 31, 32, 28, 33, 34

Mirror therapyEmerging evidence

In a pilot of 8 people, watching the reflection of the unaffected limb moving eased pain straight away in early CRPS (8 weeks or less) and reduced stiffness within the first year, but did nothing in long-standing CRPS. In 48 people with CRPS after a stroke, 4 weeks of mirror therapy added to rehabilitation reduced pain at rest by about 3 points out of 10 more than a covered mirror.

In a 2024 trial of 27 people with arm CRPS, most after a fracture, 10 minutes a day at home for 6 weeks improved movement, strength, dexterity, swelling and quality of life compared with a waiting period. Cochrane rates the evidence very low certainty, and one trial was stopped early for lack of effect. NHS advice is to keep sessions to 10 minutes or less.

Sources 35, 28, 36, 37

Exposure: ignoring the pain isn't the same as facing fearsMixed evidence

A programme that asked people to push through and ignore the pain (pain exposure physical therapy) was no better than usual care in 56 people at 9 months, though movement improved a little more. In 46 people with CRPS and at least moderate fear of movement, graded exposure to the activities they feared, with a therapist, reduced arm disability more than usual pain-guided care, after treatment and at 6 months, with less pain.

Cochrane suggests the difference lies in the approach: one tells people to ignore the pain, while the other gently tests the fear that an activity will hurt or cause harm. Both trials are small.

Sources 38, 39, 28

DesensitisationEmerging evidence

Retraining touch, with textures, water and massage, from where the skin can bear it towards the most sensitive areas, is part of the UK guideline and NHS care. It hasn't been tested on its own in a trial. Short, frequent sessions are advised, and some discomfort while you do it and shortly afterwards is expected.

Sources 1, 40, 21

Other physical treatmentsMixed evidence

For TENS (transcutaneous electrical nerve stimulation, a small device that passes a mild current through the skin), ultrasound, magnetic field treatments, carbon dioxide baths and arm cycling, Cochrane found no clear evidence. Manual lymphatic drainage didn't help pain, and laser, whirlpool baths and electroacupuncture with massage gave small, unimportant effects, all very low certainty.

NICE's chronic pain guideline, which counts CRPS as chronic primary pain, says not to offer TENS, ultrasound or interferential therapy, while the UK CRPS guideline still lists TENS among a therapist's options. There's no need to buy a TENS machine.

Sources 28, 5, 1

Medicines: a specialist decision, and UK guidance differsMixed evidence

No medicine is licensed for CRPS in the UK. The UK CRPS guideline suggests simple painkillers first, then nerve pain medicines if pain hasn't eased to a mild level after 3 to 4 weeks (NICE's first choices for nerve pain are amitriptyline, duloxetine, gabapentin or pregabalin), and a single bisphosphonate infusion (pamidronate) for suitable people within 6 months of onset.

NICE's chronic pain guideline, which treats CRPS as chronic primary pain, says to consider certain antidepressants and not to start gabapentinoids, local anaesthetics, opioids, ketamine, anti-inflammatories or paracetamol, except for gabapentinoids and local anaesthetics within a CRPS research trial.

In the trials, bisphosphonates may reduce pain soon after treatment but cause more side effects, ketamine infusions helped briefly but not in the medium term, and no trials have tested tricyclic antidepressants or opioids in CRPS. Your GP or pain specialist will weigh this with you. Don't start, stop or change a medicine yourself.

Sources 21, 1, 41, 5, 42, 43, 27

Spinal cord stimulationEmerging evidence

NICE recommends it for adults with severe nerve pain lasting at least 6 months despite usual treatment, after a successful trial of stimulation and an assessment by an experienced team. In the main trial (54 people with CRPS for 6 months or more), pain fell by 2.4 points out of 10 at 6 months with stimulation plus physiotherapy, against a slight rise with physiotherapy alone, and 39% against 6% felt much improved; function didn't improve, and 6 of the 24 people with an implant needed further procedures.

A 2024 review of trials found that pain fell with spinal cord and nerve root stimulation, but the UK guideline notes that the benefit generally fades over time.

Sources 44, 45, 46, 1

Psychological supportEmerging evidence

The UK guideline offers pain-focused psychological help, often a group pain management programme, to those who need it. NICE suggests considering acceptance and commitment therapy or cognitive behavioural therapy (CBT) for chronic primary pain, and the NHS says CBT can make it easier to keep going with rehabilitation. Seeing a psychologist doesn't mean the pain is in your mind.

Sources 1, 5, 21

Surgery, amputation and preventionEmerging evidence

The UK guideline advises avoiding surgery on a limb with CRPS where possible, and putting planned operations off until a year after it has settled; then recurrence is under 15%, mostly mild. Amputation rarely helps: in two small series, phantom pain was common and CRPS came back in the stump in about a quarter, and the guideline says it is rarely justified within 2 years.

There's no proven way to prevent CRPS, and the guideline makes no recommendation on vitamin C. Our broken wrist guide explains what the vitamin C trials found.

Sources 1, 47

Desensitisation (written steps)

From the UK guideline's appendix and NHS Ayrshire and Arran's leaflet, which follows it. Start in stage 1 and keep going.

• 1. Choose a quiet moment. Short sessions work best: even 1 to 2 minutes, as many times as you can through the day.
• 2. Start on your other, unaffected limb. Stroke it with a smooth texture, such as felt, satin, silk, velvet or a soft make-up brush, and notice how it feels.
• 3. Use the same texture on the painful limb, starting where you can bear it and working towards the more sensitive skin, for example from the top of the arm towards the hand. Look at it, think about it, and recall how the touch felt on the other side.
• 4. Vary the touch: light stroking, firm stroking, tapping and small circles.
• 5. As each one gets easier, move to rougher textures (towelling, flannel, wool, the hook side of Velcro), then to water (feel it with the other limb first, and start with a temperature you can cope with, for short spells), and to massage with a moisturiser, from the fingers or toes towards the body.
• 6. Build it into the day: feel the bed sheet, your clothes as you dress, the shower water, the washing-up water, or dough as you knead it with both hands.
• 7. It's usual for this to be uncomfortable and somewhat painful while you do it and shortly afterwards. If the pain is more than you can bear, stop that activity and choose one that is easier to tolerate.

Sources 1, 40

Looking at, touching and thinking about the limb

Many people's sense of the painful limb's size, shape and position changes. The UK guideline counts looking at, touching and thinking about the affected limb among CRPS treatments, and advises against covering it up for long. Spend short, regular moments looking at the limb, touching it gently, and noticing how it feels and where it is.

Sources 1, 49

Left and right judgements: the first stage of graded motor imagery (written steps)

From NHS Ayrshire and Arran's and East Kent's leaflets. One NHS service doesn't use graded motor imagery for people with dyslexia or for children.

• 1. Start when your therapist suggests it.
• 2. Look at pictures of hands (or feet, for CRPS in the foot) in different positions and decide, as quickly as you can, whether each one is a left or a right.
• 3. Use the app or website your therapist recommends, or make your own cards from magazine pictures or photos of family members' hands and feet.
• 4. Note how many you get right, and how fast, for each side. It isn't about getting them all right.
• 5. If the painful limb becomes more swollen or painful when you practise for a long time, stop: it should settle quickly. Keep sessions short.

Sources 48, 34

Imagined movements: the second stage (written steps)

From NHS Ayrshire and Arran's imagery leaflet and East Kent's leaflet. Start when your therapist suggests it.

• 1. Sit or lie comfortably somewhere quiet, and close your eyes or rest your gaze on one point.
• 2. Notice the sounds around you, then your breathing.
• 3. Bring your attention to your other, unaffected limb and feel its shape and size from top to bottom.
• 4. Do the same with the painful limb, noticing how it feels now, without judging it.
• 5. When your therapist says, imagine moving the painful limb, taking as long as the real movement would, in the position you'd do it in. If even imagining it hurts, start by watching other people's hands or feet move.
• 6. Finish with a few slow breaths, open your eyes, and jot down what you noticed.

Sources 49, 34

Mirror therapy: the third stage (written steps)

From NHS Ayrshire and Arran's mirror therapy leaflet and East Kent's leaflet, with the 2024 trial's dose.

• 1. Only after your physiotherapist has shown you how.
• 2. Sit comfortably with your back supported. Stand a mirror between your arms (or legs), with the reflecting side facing your unaffected limb and the painful limb hidden behind it.
• 3. Look at the reflection for a couple of minutes without moving either limb.
• 4. When that's comfortable, move both limbs slowly in exactly the same way while you watch the reflection. If pain stops the hidden limb moving, imagine moving it.
• 5. If pain or stiffness becomes a problem, stop and go back to just looking.
• 6. No more than 10 minutes at a time, 4 to 5 times a day, or as your therapist says. The 2024 trial used 10 minutes a day for 6 weeks.
• 7. Odd feelings in the hidden limb (heavier, lighter, warmer or floating) can happen and pass when you stop. If one is upsetting, stop and look at both limbs without the mirror.

Sources 37, 34, 36

The swelling routine after a fracture (written steps)

From the UK guideline's sample leaflet for people with a broken wrist. Your fracture clinic's own advice comes first.

• 1. Keep the hand raised above the level of your heart as much as you can, resting the arm out straight on pillows.
• 2. Every 15 minutes in the first days, raise the hand right up above your head and pump the fingers.
• 3. Use a sling for the first few days only.
• 4. Keep the fingers, thumb, elbow and shoulder moving, and use the hand for light tasks.
• 5. For a foot, rest it raised on pillows or a stool and keep the toes and ankle moving (our suggestion). Compression stockings or sleeves can limit swelling, especially when standing; ask your team first.

Sources 1, 26

On a flare day (written steps)

From the UK guideline and the NHS. The pain flare-up routine workout suits a bad day.

• 1. Keep doing your exercises, but more gently: fewer, smaller or shorter. The UK guideline says to reduce the intensity, not how often you do them.
• 2. Use slow breathing and relaxation, such as the slow breathing move or the breathing workout.
• 3. Pace the day: break tasks up, and rest between them.
• 4. Expect it to settle over days or a few weeks. Stress in particular can bring on a flare.
• 5. If a flare hasn't settled within a few weeks, contact your therapist or GP.

Sources 1, 3