Concept and limits of the reflex sympathetic dystrophy

Area of Science:

• Medicine
• Neurology
• Rheumatology

Background:

• Reflex sympathetic dystrophy (RSD) is characterized by pain, tissue changes, and autonomic dysfunction.
• Algidystrophy, the French term, encompasses transient regional osteoporosis and regional migratory osteolysis.
• The exact nature and boundaries of RSD remain debated.

Purpose of the Study:

• To investigate whether RSD, transient regional osteoporosis, and migratory osteolysis are distinct diseases or manifestations of a single condition.
• To question the accuracy of the classic pathophysiologic mechanism of RSD.
• To explore the limits and associations of RSD.

Main Methods:

• Analysis of 28 cases of polytopic RSD.
• Review of clinical, radiological, and scintigraphic findings.
• Investigation of potential pathophysiologic mechanisms, including immunological factors.

Main Results:

• Frequent association of RSD, transient regional osteoporosis, and migratory osteolysis in the same patients, suggesting a single disease spectrum.
• Difficulties in linking autonomic dysfunction to associated conditions like diabetes, hyperthyroidism, and malignancy.
• Demonstration of immunoglobulin deposits in RSD associated with malignancy, hinting at an immunological basis.
• Report of a unique case of Munchausen syndrome mimicking RSD.

Conclusions:

• RSD, transient regional osteoporosis, and migratory osteolysis are likely different manifestations of a single disease.
• The classic pathophysiologic mechanism of RSD may be incomplete, with potential immunological involvement.
• The spectrum of RSD may extend to conditions like aseptic necrosis of the hip.