Diagnosis of Complex Regional Pain Syndrome Diagnosis of complex regional pain syndrome is primarily clinical, relying on a detailed history, symptom presentation, and physical examination. Because there is no single definitive test, diagnosing complex regional pain syndrome can be challenging and often involves ruling out other potential conditions with similar symptoms. The most widely accepted criteria for diagnosing CRPS are known as the Budapest Criteria, which require: Continuing pain that is disproportionate to any known inciting event At least one symptom in three of the four categories: sensory, vasomotor, sudomotor/oedema, and motor/trophic At least one sign at the time of evaluation in two or more of the same categories Assessment and Examination Doctors will examine: Skin temperature and colour changes Swelling and sweating patterns Sensitivity to touch or movement Range of motion and motor function A thorough history is also essential. Patients are asked about the onset, severity, and progression of symptoms, as well as any recent injuries, surgeries, or immobilisations. Diagnostic Tests | Diagnosis of Complex Regional Pain Syndrome While no test can confirm CRPS definitively, additional investigations help exclude other causes: X-rays or bone scans: May show changes in bone density or structure MRI or ultrasound: Helps assess tissue changes and swelling Thermography: Measures skin temperature differences between limbs Nerve conduction studies: Rule out other nerve conditions In cases of suspected CRPS-II, which involves known nerve damage, nerve studies may help determine the extent of the injury. Because CRPS can mimic other conditions such as neuropathies, arthritis, or infection, a multi-disciplinary approach is often beneficial, involving pain specialists, neurologists, rheumatologists, and physiotherapists. In summary, the diagnosis requires careful clinical judgement and a process of exclusion. Early recognition is vital, as delayed diagnosis can lead to worse outcomes and more entrenched symptoms. [Next: Treatment of Complex Regional Pain Syndrome →]