Distinguishing inflammatory pain from centralized pain

FeatureInflammatory painCentralized pain
LocationHands, wrists, cervical spine, knees, hips, ankles, feetMore diffuse, “all over,” tender points
Relationship to time of dayNocturnal, with rest, early morningNocturnal, with rest, early morning
Relationship to exertionBetter with exertionBetter during exertion, worse after
Character of painConstant, dull, achyIntermittent, stabbing, burning, “like being hit by a truck,” “unbearable”
DurationVariableOften many years
General associated symptoms and signsFatigue, fever, other organ signs and symptomsFatigue, weakness, headaches, irritable bowel syndrome symptoms, cognitive impairment, disturbed sleep, mood disorders, dry eyes and mouth, light sensitivity, difficulty swallowing, sensation of swollen glands in neck, urinary frequency, feeling faint after hot shower or in hot weather
Localized associated symptoms and signsStiffness ≥ 60 minutes
Objective swelling
Stiffness ≥ 60 minutes
Lack of objective findings
Tender points
Allodynia (pain from normally nonpainful stimuli), hyperalgesia (increased sensitivity to pain)
Acrocyanosis (bluish coloring of hands and feet)
Brisk reflexes
Laboratory resultsInflammatory picture: elevated C-reactive protein and Westergren sedimentation rate, anemia, occasionally elevated platelet count, positive serologies (rheumatoid factor, anti-cyclic citrullinated peptide, extractable nuclear antigen panel)Normal