Definition: benign mucin-filled cyst that develops along tendons or joints and has no true epithelial lining
Epidemiology: most common type of hand mass
Location: wrist and fingers (most common at the dorsal wrist)
Pathophysiology: herniation of connective tissue associated with repetitive trauma and mucoid degeneration of periarticular structures → sac that is lined with synovial cells and contains paucicellular connective tissue (typically mucin)
Clinical features
Usually asymptomatic but can occasionally cause joint pain
Fluctuant, transilluminant swelling
Can lead to nerve compression, which may cause numbness, weakness, or tingling (e.g., Guyon tunnel syndrome)
