What are the key clinical features to consider when diagnosing Complex Regional Pain Syndrome (CRPS) in a primary care setting?

Key clinical features to consider when diagnosing Complex Regional Pain Syndrome (CRPS) in primary care include:

• Persistent regional pain that is disproportionate to any inciting event, often described as burning or aching, and typically affecting a limb NICE NG193 Ferraro et al. 2024.
• Sensory changes such as allodynia (pain from normally non-painful stimuli) and hyperalgesia (increased pain from painful stimuli) are common and important diagnostic clues NICE NG193 Gharibo et al. 2025.
• Vasomotor symptoms including skin colour changes (redness, pallor, or cyanosis) and temperature asymmetry between affected and unaffected limbs should be assessed NICE NG193 Ferraro et al. 2024.
• Sudomotor/edema signs such as swelling, sweating abnormalities, or changes in skin texture (shiny or thin skin) are frequently present and support the diagnosis NICE NG193 Gharibo et al. 2025.
• Motor/trophic changes including decreased range of motion, weakness, tremor, or dystonia, as well as hair and nail growth abnormalities, are key features to evaluate NICE NG193 Ferraro et al. 2024.
• Temporal pattern is important: symptoms usually develop within weeks of an injury or surgery but may be delayed; the clinical picture evolves over time NICE NG193 Ferraro et al. 2024.
• Exclusion of other diagnoses is essential in primary care, as CRPS remains a diagnosis of clinical criteria supported by the Budapest criteria, which require the presence of continuing pain disproportionate to any inciting event plus signs in sensory, vasomotor, sudomotor/edema, and motor/trophic categories NICE NG193 Gharibo et al. 2025.

In summary, primary care clinicians should focus on a detailed history and physical examination identifying disproportionate pain, sensory abnormalities, vasomotor and sudomotor changes, and motor/trophic signs, while excluding other causes. Early recognition using these clinical features facilitates timely referral and management NICE NG193 Ferraro et al. 2024Gharibo et al. 2025.