The CRPS diagnosis can be very challenging

A diagnosis is based on a few variables; a person’s medical history, physical symptoms,and medical diagnostics. 

SYMPTOMS

Using Budapest Criteria, as a diagnosis of CRPS, a patient must have at least one symptom in three of the following four categories: Sensory: an abnormal increase in sensitivity (hyperesthesia) and/or allodynia Vasomotor: skin color changes or temperature and/or skin color changes between the limbs Sudomotor: swelling (edema) and/or sweating differences between the limbs; Motor: decreased range of motion and/or motor dysfunction, tremors/ muscular spasms (dystonia) and/or trophic changes (changes to hair/nails and/or skin).

SIGNS

At the examination, at least one sign must be present in two or more of the following categories:

  • Sensory: hyperalgesia (to pinprick) and/or allodynia, deep somatic (physical) pressure
  • Vasomotor: temperature differences between the limb and/or skin color changes and/or skin color changes between the limb;
  • Sudomotor: edema and/or sweating changes and/or sweating differences between the limbs;
  • Motor/trophic: decreased range of motion and/or motor dysfunction (i.e. weakness, tremor or muscle spasm) and/or trophic changes.

Budapest Criteria

The Budapest Criteria are a set of diagnostic criteria for Complex Regional Pain Syndrome (CRPS). They were developed to improve the accuracy of CRPS diagnosis by incorporating both symptoms and signs, leading to better sensitivity and specificity compared to previous diagnostic tools. The criteria focus on sensory, vasomotor, sudomotor/edema, and motor/trophic abnormalities, both reported by the patient (symptoms) and observed by the clinician (signs). 

Testing and CRPS

Thermography

One of the most useful tests in diagnosing CRPS is thermography.

Thermography is a visual mapping of the skin. A person’s skin temperature is controlled by their sympathetic nervous system. 

Thermography can show temperature differences down to 1/10th of one degree centigrade.  If there is a difference one degree centigrade from one limb to the other, that would mean the sympathetic nervous system was malfunctioning hence a diagnosis of CRPS.

Testing may also be used to help rule out other conditions, such as arthritis, Lyme disease, Fibromyalgia, etc.