I hear this every single day in my Hoffman Estates practice: “I had a wrist fracture six months ago, the bone is healed, and my hand is now burning, swollen, color-changed, and so sensitive I can’t put a sleeve over it.” Or: “My ankle sprain was three months ago — the orthopedic surgeon says everything looks fine, but my foot is on fire and the skin won’t stop changing colors.” Or: “I had carpal tunnel surgery a year ago and my whole hand is worse than it was before.” For these patients, the diagnosis is almost always Complex Regional Pain Syndrome (CRPS), and the treatment is unusual in pain medicine: it is a coordinated, sequential treatment pathway — not a single procedure. Done early and done in the right order, CRPS responds. Done late or done in the wrong order, it becomes one of the most stubborn pain conditions in medicine. As a triple board-certified pain medicine specialist (ABA Anesthesiology, ABA Pain Medicine, ABIPP), and as Chair of the ASPN Healthy Longevity & Age-Related Pain Committee, I treat CRPS with a clear protocol grounded in the 2022 Harden CRPS Practical Diagnostic and Treatment Guidelines (5th ed.) [PMID 35802045]. The honest version is this: I’d rather not do the wrong procedure than do any procedure — and that is especially true for CRPS, where treatment is sequential and patient-specific.

What CRPS actually is

CRPS is a chronic regional pain condition that develops after an injury, surgery, fracture, immobilization, or — sometimes — without any identifiable trigger at all. The hallmark is pain that is disproportionate to the inciting event: a wrist fracture that heals on imaging, but the hand remains in a burning, electric, allodynic state for months. Along with the pain come the cardinal features that distinguish CRPS from a more ordinary nerve injury: sensory changes (hyperalgesia, allodynia — pain to light touch), vasomotor changes (skin color and temperature shifts, often side-to-side asymmetric), sudomotor / edema changes (swelling, abnormal sweating), and motor / trophic changes (weakness, tremor, dystonia, hair and nail changes, skin atrophy). The condition was previously called “reflex sympathetic dystrophy (RSD)” and “causalgia”; the modern terminology is CRPS Type I (no identifiable nerve injury) and CRPS Type II (a defined major nerve injury, formerly causalgia).

CRPS most commonly affects a single limb — a hand, an arm, a foot, a leg — though it can spread regionally over time if untreated. The mechanism is not fully understood, but it appears to involve a combination of peripheral nerve sensitization, central nervous system sensitization, neurogenic inflammation, sympathetic nervous system dysregulation, and autoimmune phenomena. That complexity is exactly why no single treatment cures CRPS in most patients — and why a sequential, multimodal pathway is the standard of care.

Early diagnosis matters — read this twice

This is the part I want you to read twice. CRPS treated within the first 6 months has dramatically better odds of meaningful recovery than CRPS treated late. [cite needed — Harden 2022 references the early-treatment window throughout] The longer the condition persists in a sensitized, untreated state, the more entrenched the central nervous system changes become, the less reversible the dystrophic and motor features get, and the harder the condition is to turn around. I see this in my practice every week: the patients who do best are the ones who were diagnosed correctly within weeks of onset and started on a coordinated treatment pathway. The patients who struggle most are the ones who were told “your fracture is healed, you should be fine, it’s in your head” for months on end before someone finally said the word “CRPS.”

If you’re reading this page within the first six months of an injury or surgery and you have burning regional pain, skin color changes, and sensitivity beyond what your tissue findings explain — don’t wait. Call. Even if you’re not sure. An early evaluation costs you a visit; a delayed diagnosis can cost you the chance at the best outcome.

Confirming the diagnosis — the Budapest Criteria

The diagnosis of CRPS is clinical. There is no single blood test, imaging study, or nerve test that confirms it. The modern diagnostic standard, codified by Harden and colleagues, is the Budapest Criteria — a structured set of clinical findings that the patient must report (symptoms) and the examiner must observe (signs) across four domains: sensory, vasomotor, sudomotor/edema, and motor/trophic.

To meet diagnostic criteria, the patient must:

  • Have continuing pain disproportionate to any inciting event.
  • Report at least one symptom in three of the four categories at any point during the illness (sensory, vasomotor, sudomotor/edema, motor/trophic).
  • Demonstrate at least one sign in two or more of those four categories at the time of evaluation.
  • And have no other diagnosis that better explains the signs and symptoms.

That last bullet is the most clinically important — and the one I take most seriously. CRPS is partially a diagnosis of exclusion. Before we settle on it, I want to be sure we have ruled out a nerve compression, a missed orthopedic injury, an infection, a vascular problem, a rheumatologic process, and other conditions that can mimic CRPS at a glance. Adjunctive studies — three-phase bone scan, plain films, MRI, autonomic testing, nerve conduction studies, thermography — are sometimes helpful when the clinical picture is ambiguous, but they are not required for the diagnosis and the Budapest Criteria do not depend on them.

Who I treat — and who I refer first

The patient profile for CRPS treatment in my practice has a clear pattern. I treat:

  • Adults with a clinical diagnosis of CRPS Type I or Type II by the Budapest Criteria, in a single limb or in a regional distribution.
  • Patients within 6 months of onset, where early aggressive multimodal treatment is most effective — this is the window I most want to catch.
  • Patients with established CRPS who have failed initial conservative measures and need escalation — sympathetic blocks, neuromodulation, advanced infusion options.
  • Patients with refractory upper-extremity CRPS who may be candidates for the Bier block — an intravenous regional anesthesia technique that delivers anti-sensitization medications directly to the affected limb under tourniquet (see Bier block for the full procedure detail).
  • Patients whose CRPS is sympathetically maintained — meaning a diagnostic sympathetic block (stellate ganglion for upper extremity, lumbar sympathetic chain for lower extremity) reduces their pain meaningfully — which directs the rest of the treatment ladder.

I will be direct about who I refer first or in parallel:

  • Pediatric CRPS — children and adolescents respond to a different treatment emphasis (heavy on intensive physical therapy programs and cognitive behavioral therapy) and are best managed in a dedicated pediatric pain program.
  • CRPS with a major unaddressed psychiatric comorbidity — severe untreated depression, active substance use disorder, untreated PTSD. These do not exclude CRPS treatment, but they need parallel attention from the right team to make the pain treatment work.
  • CRPS with an identifiable surgically correctable lesion (e.g., a clearly compressed nerve in CRPS Type II) — the upstream lesion gets evaluated first.

The CRPS treatment pathway — what we actually do, and in what order

This is the section that matters most. CRPS is the page on this site where the structural template is unusual: it is not a single procedure with a candidacy filter and a recovery window — it is a coordinated, sequential pathway. Here is how I run that pathway in my Hoffman Estates practice, anchored in the 2022 Harden guidelines.

Step 1 — Diagnostic confirmation and baseline workup

The first visit establishes the diagnosis (Budapest Criteria), documents baseline pain, function, and the four-domain symptom profile, and rules out competing diagnoses. We get appropriate imaging if it hasn’t been obtained, screen for nerve compression mimics, and assess for psychiatric comorbidity that needs parallel attention. We start a written CRPS treatment plan that the patient gets a copy of — written, dated, and revisited at each visit.

Step 2 — Functional restoration as the spine of treatment

The Harden 2022 guidelines are unambiguous: functional restoration — physical therapy and occupational therapy aimed at desensitization, edema management, range of motion, and graded exposure of the affected limb — is the foundation of CRPS treatment. Everything else we do is in service of letting the patient participate more fully in functional restoration. I coordinate with a small group of physical and occupational therapists who actually understand CRPS — the desensitization protocols, the graded motor imagery, the mirror therapy. Patients who do PT/OT alone do better than patients who get blocks alone. Patients who get both, in the right order, do best.

Step 3 — Pharmacologic management

Medications are an adjunct, not the headline. The Harden 2022 guidelines support a multimodal approach with a tiered ladder typically including: neuropathic medications (gabapentin or pregabalin, sometimes a tricyclic antidepressant or duloxetine), bisphosphonates in early CRPS (the evidence on bisphosphonates such as pamidronate or neridronate is strongest in the early-onset window), NSAIDs for inflammatory phase symptoms, topical agents (topical lidocaine, topical ketamine compounds, capsaicin in select cases), and — used carefully and time-limited — short courses of corticosteroids in the very early inflammatory phase. Long-term opioids are not first-line in CRPS and the literature has moved away from opioid reliance for this condition. I prescribe medications individualized to each patient’s presentation, contraindications, and response, and we revisit the medication list at every visit rather than just refilling it.

Step 4 — Sympathetic nerve blocks (diagnostic AND therapeutic)

For most adults with CRPS who haven’t already had them, sympathetic nerve blocks are the next interventional step. The block both confirms whether the CRPS is sympathetically maintained and delivers therapeutic benefit by interrupting the abnormal sympathetic outflow to the affected limb.

For upper-extremity CRPS, the relevant block is a stellate ganglion block (SGB) — a fluoroscopy-guided injection of local anesthetic onto the stellate (cervicothoracic) sympathetic ganglion at the base of the neck. The block typically produces a brief Horner’s syndrome on the same side (pupil constriction, eyelid droop, facial flushing) confirming a successful sympathetic interruption.

For lower-extremity CRPS, the relevant block is a lumbar sympathetic block — fluoroscopy-guided injection of local anesthetic onto the lumbar sympathetic chain alongside the lower lumbar vertebrae. A successful block produces warming of the affected foot, often visible and measurable.

The diagnostic threshold is the same as for other diagnostic blocks: at least 50% pain reduction during the duration of the anesthetic, in the affected limb, with relief that correlates with the clinical pattern. A series of three to six sympathetic blocks at intervals is the typical therapeutic course when the diagnostic block confirms sympathetically maintained CRPS — combined with intensive PT/OT during the window of improved pain.

A negative or minimally helpful diagnostic sympathetic block tells us something important too: the CRPS is sympathetically independent, and the treatment emphasis shifts away from repeat blocks and toward systemic medications and earlier consideration of neuromodulation.

Step 5 — Bier block for refractory upper-extremity CRPS

For upper-extremity CRPS that has not adequately responded to stellate ganglion blocks plus PT/OT, the Bier block is a focused, limb-specific intervention worth knowing about. The Bier block (intravenous regional anesthesia of the affected limb) places a tourniquet on the upper arm, exsanguinates the limb of blood, and infuses a measured dose of medication — historically guanethidine, more commonly today a combination of lidocaine and an adjuvant such as ketorolac or clonidine — directly into the isolated venous compartment of the painful arm. The tourniquet is held for a defined time, allowing the medications to soak into the sensitized tissue without systemic distribution. Bier block is not first-line CRPS treatment, but for the right refractory upper-extremity patient, it is a meaningful tool in the ladder before we escalate to permanent neuromodulation. (Read the full procedural detail on the Bier block page.)

Step 6 — Neuromodulation: DRG stimulation for refractory CRPS

For CRPS that remains refractory to sympathetic blocks, medications, and intensive functional restoration, the next step in the ladder is neuromodulation — and for CRPS specifically, the strongest evidence is for dorsal root ganglion (DRG) stimulation.

The ACCURATE study (Deer et al., 2017) was the pivotal randomized controlled trial comparing DRG stimulation head-to-head against traditional spinal cord stimulation for CRPS and causalgia of the lower extremity [Pain 2017; PMID 28178071]. At 3 months, 81.2% of DRG patients achieved ≥50% pain relief, compared to 55.7% of SCS patients. The DRG advantage held at 12 months. ACCURATE is one of the strongest pieces of evidence in interventional pain medicine for any single device-condition pairing, and it has reshaped the way our field treats lower-extremity CRPS.

For the patient with refractory CRPS in a single lower extremity — a foot, a knee, a single leg — DRG stimulation is my default first-line neuromodulation choice. For refractory CRPS with a broader or more diffuse distribution, spinal cord stimulation (SCS) remains the appropriate option. Every neuromodulation candidate completes a 7-day external trial before any permanent implant decision, with the same ≥50% pain-reduction-plus-functional-improvement threshold I apply to every neuromodulation patient. (Read more on DRG stimulation and spinal cord stimulation, and on the comparison of the two for focal versus diffuse pain patterns.)

Step 7 — Continued multimodal maintenance

Even after a successful neuromodulation implant, the CRPS patient is not “fixed.” The functional restoration work continues. The medications get fine-tuned. The follow-up cadence is closer than for most pain conditions because CRPS can wax and wane, can spread regionally, and can require re-engagement of earlier rungs of the ladder if a flare occurs. Most of my CRPS patients I see at intervals indefinitely — at minimum two to three times a year once stable, more often during a flare or after a new intervention.

What the procedures look like

Because this page covers a pathway rather than a single procedure, the day-of-procedure detail varies by step. In brief:

Sympathetic block (stellate or lumbar). Outpatient, fluoroscopy-guided, typically 20-30 minutes, performed with local anesthetic at the skin and light sedation if the patient prefers. For stellate ganglion block, the patient lies supine with neck extended; the needle is placed at the anterior tubercle of the C6 transverse process, contrast confirms position and absence of vascular uptake, and local anesthetic is injected. For lumbar sympathetic block, the patient lies prone; the needle is advanced lateral to the L2 or L3 vertebral body alongside the sympathetic chain, contrast confirms position, and local anesthetic is injected. You’ll be observed for 30-60 minutes afterward — the goal is to confirm the expected sympathetic response (Horner’s syndrome for stellate, foot warming for lumbar) and to start a pain diary. Most patients go home the same day with a driver.

Bier block. Outpatient, typically 60-90 minutes including the tourniquet time. An IV is placed in the affected arm; the arm is elevated and exsanguinated with a compression bandage; a double-cuff pneumatic tourniquet is inflated to suprasystolic pressure; the medication mixture is infused via the IV; the tourniquet is held for the protocol time; then released in a controlled, monitored fashion. (Full detail on the Bier block page.)

DRG or SCS trial / permanent implant. Outpatient procedures, fluoroscopy-guided, with the 7-day trial preceding any permanent implant decision. (Full detail on the DRG stimulation and spinal cord stimulation pages.)

Risks across the pathway

CRPS treatment risks are step-specific. Sympathetic blocks: transient hoarseness or temporary swallowing change after stellate ganglion block, transient leg warmth and rarely transient ejaculatory or autonomic effects after lumbar sympathetic block, bleeding, infection, vascular injury, intravascular injection, and — rarely — pneumothorax (stellate). Bier block: tourniquet pain, transient hand or arm numbness, rarely systemic toxicity if the tourniquet fails. DRG and SCS: lead migration, infection, seroma, and the rare neurologic complications described on the respective procedure pages. I screen anticoagulation, dental work, and active infection at each step.

How I decide between the options

This is the trust-builder section, and the reason CRPS is unusual on this page: the decision is sequential, not binary. Here is how I decide what’s next for a given CRPS patient.

If the diagnostic sympathetic block is meaningfully positive, the patient gets a therapeutic series of sympathetic blocks combined with intensive PT/OT during each window of improved pain. This often holds the condition until functional restoration takes over.

If the diagnostic sympathetic block is negative or minimally helpful — i.e., sympathetically independent CRPS — we shift earlier toward medications optimization and toward neuromodulation candidacy assessment. We do not chase a negative block with more of the same.

If we’ve completed sympathetic blocks, optimized medications, done the PT/OT work, and the upper-extremity CRPS patient is still suffering, the next rung is the Bier block — a focused, limb-specific intervention before committing to permanent hardware.

If we’ve climbed the full ladder and the patient still has refractory CRPS, neuromodulation. DRG stimulation for focal lower-extremity CRPS (ACCURATE evidence). SCS for broader or upper-extremity refractory distributions where DRG isn’t appropriate. Every neuromodulation candidate trials first.

If the patient is within the first 6 months of CRPS onset, we move through the early steps faster and with more intensity. Time is the most important variable in CRPS — and the only one we cannot get back. I’d rather treat aggressively early than chase residual disease for years.

When I wouldn’t recommend a CRPS-targeted intervention. When the diagnosis is uncertain and a competing diagnosis hasn’t been ruled out. When a major untreated psychiatric comorbidity needs parallel work first. When the patient hasn’t had a fair trial of the previous rung of the ladder. When the upstream tissue problem (a compressed nerve, a missed orthopedic injury) needs to be addressed first. I’d rather not do the wrong procedure than do any procedure.

Insurance and prior authorization

The components of the CRPS pathway are individually covered by Medicare and most major commercial insurers in Illinois — the sympathetic blocks, the Bier block (with appropriate documentation), DRG and SCS (with the standard documentation of failed conservative care, a psychological evaluation, and a successful trial). What is unusual about CRPS coverage is that the pathway is sequential — most insurers will not authorize the larger interventions (DRG or SCS) without documentation that the earlier rungs (PT/OT, medications, sympathetic blocks) were tried first. My office handles the prior authorization paperwork step by step, including the clinical letter documenting the CRPS diagnosis under the Budapest Criteria, the response to each prior intervention, and the rationale for the next step.

Frequently asked questions

Is CRPS curable?
“Cure” is the wrong frame for most CRPS patients. With early, coordinated, multimodal treatment, a substantial proportion of patients achieve meaningful — sometimes dramatic — improvement in pain and function, and many enter long, stable remissions. Late-treated CRPS is harder to turn around but can still be meaningfully improved with the right pathway. The honest version is this: CRPS is a condition we treat actively and manage long term, the same way we approach other chronic neuroinflammatory conditions.

How is CRPS diagnosed?
By the Budapest Criteria — a structured set of clinical findings in four domains (sensory, vasomotor, sudomotor/edema, motor/trophic) combined with the requirement that no other diagnosis better explains the picture. The diagnosis is clinical. Imaging and nerve studies are sometimes useful adjuncts but are not required and do not “rule in” CRPS by themselves.

Why does early treatment matter so much?
The longer CRPS persists in a sensitized, untreated state, the more entrenched the central nervous system and dystrophic changes become, and the harder the condition is to reverse. Patients treated within the first 6 months of onset have meaningfully better outcomes than patients treated late. If you suspect CRPS, do not wait.

Do I have to start with sympathetic blocks, or can I go straight to a stimulator?
With rare exceptions, no — and the reason is both clinical and practical. The sympathetic block is a key diagnostic step (it tells us whether the CRPS is sympathetically maintained), is therapeutic in its own right, and is required by most insurers in the documentation pathway before a stimulator is authorized. The exception is when sympathetic blocks have already been done elsewhere and clearly failed.

What is the difference between DRG and SCS for CRPS?
For focal lower-extremity CRPS — one foot, one knee, one leg — DRG stimulation has the strongest evidence (ACCURATE study) and is my default first neuromodulation choice. For broader, more diffuse, or upper-extremity refractory CRPS where DRG anatomy isn’t appropriate, SCS remains the right option. Every neuromodulation patient does a 7-day trial first.

Can CRPS spread to other limbs?
Yes, in some patients, CRPS can spread regionally — to a contralateral limb (mirror spread), to a contiguous body region, or rarely more broadly. Spread is one of the reasons we treat aggressively early. If you notice new symptoms in a different limb, call promptly — earlier re-engagement of treatment is better than waiting.

If you’re concerned about CRPS

If you have burning, sensitive, color-changing pain in a limb that is out of proportion to the original injury, and you’ve been told to “wait and see” for weeks or months — please don’t wait any longer. Call my Hoffman Estates, Illinois office at (847) 981-3630 to schedule a consultation. The window for the best outcomes is the first six months, and the right next step is rarely the most invasive one. We’ll work through the diagnosis with you carefully, build a written treatment plan, and walk the ladder together — only one rung at a time, and only with the rung that’s actually right for you.