Digital Mucous Cyst

Digital mucous cysts are benign, cystic lesions of the digits typically located near the distal interphalangeal joints or near the proximal nail folds. The peak incidence rates are in the age group between 40 and 70 years. The male to female ratio is 2:1. Two types of digital mucous cysts have been described. The myxomatous (superficial) type presumably arises de novo from the metabolic derangement of dermal fibroblasts that leads to excess production of hyaluronic acid. The ganglionic (deep) type results from leakage of fluid from the distal interphalangeal joint. There may be coexisting osteoarthritis and osteophytes in the joint. Characteristically, a digital mucous cyst presents as an asymptomatic, slow-growing, solitary, circumscribed, semi-translucent, flesh colored, compressible, domeshaped, cystic papulonodule measuring 1 to 10 mm in diameter on the finger. A watchful observation may be appropriate for asymptomatic patients. For symptomatic patients and those patients who prefer treatment, simple surgical excision of the cyst is the treatment of choice. Other treatment options include incision and drainage, repeated needling to induce scarification, cryotherapy, sclerotherapy, intralesional injections of corticosteroids or sclerosing agents, electrodessication, and carbon dioxide laser therapy.