Complex regional pain syndrome (CRPS)

What is CRPS?

CRPS is a syndrome characterized by persistent, disproportionate pain and autonomic dysfunction of an extremity. It usually occurs after fractures (e.g. radius), ligament injuries, contusions or operations and often affects the hand/forearm.

• CRPS type I: without detectable major nerve lesion (more common).
• CRPS type II: with proven peripheral nerve injury (formerly causalgia).
• Pathophysiology: Interaction between excessive inflammatory response, sensory nerve hyperexcitability (central sensitization) and vegetative dysregulation (blood circulation, sweating), accompanied by motor and trophic changes.

Important: CRPS is not just a psychological “increase in pain”. Psychological factors can influence the course, but are not the cause.

Triggers and risk factors

A triggering event can usually be named. However, the extent of the symptoms is often greater than would be expected after the original injury.

• Typical triggers on the hand/wrist: distal radius fracture, scaphoid injury, ligament ruptures, tendon or nerve sutures, arthroscopic or open operations, long immobilization in a cast.
• Favoring factors: severe acute pain, immobilization that is too tight, nicotine consumption, older age, female gender; the evidence is partly heterogeneous.
• CRPS can also occur after seemingly minor trauma (e.g. bruises, stab wounds).

Adequate pain treatment immediately after injury/surgery, early functional therapy and avoiding unnecessarily long immobilization can be helpful as a preventive measure.

Symptoms: How do I recognize CRPS?

The symptoms often appear within weeks of the triggering event. The course can be phased, but varies greatly from person to person.

• Pain: persistent, burning/stinging, extending beyond trauma; Allodynia (pain upon light touch), hyperalgesia (increased pain response).
• Swelling and skin changes: redness or pallor, temperature differences, changed sweating.
• Movement: Stiffness, weakness, tremor, or dystonia; protective posture.
• Tropics: Skin is shiny, hair/nails grow differently, soft tissues appear swollen or later atrophic.
• Function: Uncertainty in using the hand, avoidance, reduced fine motor skills.

The previously popular 3-stage model (acute-dystrophic-atrophic) is too rigid. Today the following applies: symptoms can overlap and change over time.

Warning signs: When should you seek medical advice immediately?

• Increasing severe pain with redness, warmth and fever: suspected infection.
• Cold, pale, numb hand segment with increasing weakness: circulation or nerve compression problem.
• Violent swelling with a feeling of tension, dyspnea/leg pain: think of thrombosis/embolism (rarely in the arm, but serious).
• Newly occurring paralysis or persistent nighttime numbness: rule out nerve congestion.

Differential diagnoses of the hand and wrist

CRPS is a diagnosis of exclusion based on clinical criteria. The following illnesses can cause similar symptoms or may also occur:

• Nerve constriction syndromes: carpal tunnel, cubital tunnel, Guyon box or radial tunnel syndrome.
• Peripheral nerve injuries, neuromatous pain.
• Infections (e.g. joint/soft tissue), inflammatory arthritis, gout/pseudogout.
• Impaired fracture healing, implant problems, tendon complications.
• Polyneuropathies (metabolic/toxic), sensory disorders without a clear structural cause.
• Vascular problems (arterial/venous), lymphedema.

Diagnostics: Budapest criteria and useful examinations

The diagnosis of CRPS is clinical. The internationally established Budapest criteria help to confirm the diagnosis and rule out other causes.

Apparatus diagnostics serve to exclude alternatives and assess progress:

• X-ray/MRI: fracture-related problems, bone marrow edema, soft tissue complications; CRPS-specific findings are uncertain.
• Three-phase bone scintigraphy: can help in the early stages, but is not mandatory.
• Thermography/quantitative sensor technology: Supplement in special cases.
• Laboratory: Rule out signs of infection/inflammation.

Therapy: conservative first – combined individually

The goals are pain relief, calming inflammation, maintaining/improving mobility and function as well as everyday reintegration. What is crucial is an early start, a phased approach and realistic expectations. Not every measure is suitable for everyone - we put together a personal plan.

Non-drug building blocks

• Hand therapy/physiotherapy: pain-adapted mobilization, active exercises in short, frequent intervals; Avoiding rigid immobilization.
• Occupational therapy: functional tasks, fine motor skills, everyday strategies; short-term, targeted splints for pain and edema control.
• Desensitization: graduated stimulation habituation (various textures, brushes, vibration), mirror therapy and graded motor imagery to reorganize pain processing.
• Lymphatic drainage/edema management: elevation, compression according to instructions (if tolerated).
• Physical measures: TENS, test heat/cold carefully (note temperature hypersensitivity).
• Education and psychology: understanding pain, stress/sleep management, behavioral therapy strategies for fear movement (fear avoidance) – psychological support if necessary.

Medication options (individual, time-limited, benefit-risk assessment)

• NSAIDs/analgesics for acute relief; Be aware of stomach/kidney risks.
• Corticosteroids: worth considering for a short time in the early, highly inflammatory stage; Indication and dose individual.
• Neuropathic painkillers: e.g. B. Gabapentin/Pregabalin, Amitriptyline/Duloxetine to dampen neuropathic components.
• Topical options: lidocaine patches, capsaicin-containing preparations (in experienced hands).
• Bisphosphonates: in studies, some effective for CRPS-associated bone pain; Check indication carefully.
• Calcitonin/Vitamin C: Evidence mixed; can be discussed in selected situations (vitamin C is sometimes examined prophylactically after a radius fracture).

Interventional (if there is no progress despite consistent conservative measures, preferably in specialized centers)

• Sympathetic blockades (e.g. stellate ganglion) for diagnostic and short-term therapeutic testing.
• Intravenous regional anesthesia (Bier block) with additives in selected cases.
• Ketamine infusions: Off-label, only with narrow indications and monitoring in pain medicine.
• Neuromodulation: Spinal cord stimulation or dorsal root ganglion stimulation for treatment-refractory disease after interdisciplinary evaluation.

Surgery: Reserved. Surgery can trigger or worsen CRPS. Surgery is particularly considered for CRPS type II if a clearly treatable nerve lesion (e.g. bottleneck/neuroma) or a mechanical problem (e.g. interfering implants) has been reliably identified. The decision is made interdisciplinary and after weighing up the risks.

Everyday life, self-help and prognosis

Many cases of CRPS improve within months, some require more time. Some of those affected retain residual symptoms. Early diagnosis, activation and consistent therapy improve the chances of functional gain.

• Active breaks instead of constant stress: short, frequent exercise sessions are often better tolerated.
• Dosing the treatment gently: complete avoidance increases stiffness - targeted, pain-adapted use promotes healing.
• Temperature management: avoid extreme cold/heat, test lukewarm applications.
• Skin care: mild care products, protection against injuries; Observe nail/hair changes.
• Sleep and stress: relaxation techniques, sleep hygiene; psychological support if necessary.
• Reduce/quit smoking: promotes blood circulation and healing.
• Work/stress: gradual reintegration, ergonomic adjustments; Certificates and rehabilitation options individually.

CRPS treatment in our practice in Hamburg

As an orthopedic specialist practice with a focus on the hand/wrist at Dorotheenstrasse 48, 22301 Hamburg, we provide you with structured and interdisciplinary support. We focus on conservative, function-preserving measures and, if necessary, coordinate closely with hand therapy, pain medicine and psychology.

• Careful anamnesis, examination of the Budapest criteria, exclusion of relevant differential diagnoses.
• Early functional, individually dosed exercise program – in cooperation with experienced hand therapists.
• Evidence-based pain and inflammation management; common goal setting and follow-up checks.
• Education about self-management, warning signs and realistic healing processes.
• For complex courses: involvement of specialized centers for further procedures.

We take time to answer your questions and plan the next steps together - transparently and without promises of healing.