Dorsal cyst mucoid D21.1

Hyde, 1883

Benign, mostly asymptomatic, skin-colored or slightly opalescent pseudocyst with gelatinous content. Frequently communicating with cleft digital interphalangeal joints and occasionally associated with osteoarthritis.

Most frequent tumor of the fingers or toes. w>m.

Trauma is considered the cause. A connection with mucoid degeneration of the connective tissue structures of the fingers or toes near the joints is also being discussed.

40 to 60 years of age

0.3-1.5 cm large, rough, predominantly painless, only occasionally painful, translucent, light grey bulges of the proximal nail fold. Often spontaneous rupture. A glassy, gelatinous liquid is discharged. If localized under the nail matrix mostly reddened lunula. In the case of prolonged dorsal cysts a longitudinal, channel-shaped nail dystrophy develops.

Flat extended epidermal band. Pseudocyst (no epithelial lining) usually in the upper dermis. This contains mucin rich in hyaluronic acid, which stains with alcian blue. Frequently fibrosed connective tissue in the immediate vicinity of the cyst lumen. Inflammatory infiltrates are absent.

Myxoid degenerated fibrohistiocytic tumors. In the rarely occurring verrucous surface of mucoid dorsal cysts, vulgar warts must also be differentiated in the differential diagnosis, whereby the diagnosis can only be made histopathologically in this case

Try compression therapy for several weeks (may be successful).

Another option is aspiration, or incision and expression of the cyst contents, and intracystic application of a glucocorticoid crystal suspension (e.g. 40 mg triamcinolone). Subsequently, compression bandages are applied for several weeks.

In case of failure of conservative therapy approaches: Complete extirpation in toto under block anaesthesia and under tourniquet. Postoperative immobilization with plaster splint for 10 days.

Cave! Risk of injury to the nail root! The patient must be urgently informed that this complication may occur (consequence: longitudinal nail dystrophy or splitting of the nail!)

1. de Berker D, Lawrence C (2001) Ganglion of the distal interphalangeal joint (myxoid cyst): therapy by identification and repair of the leak of joint fluid. Arch Dermatol 137: 607-610
2. Hernandez-Lugo AM (1999) Digital mucoid cyst: the ganglion type. Int J Dermatol 38: 533-535
3. Marzano AV et al (1997) Unique digital skin lesions associated with systemic sclerosis. Br J Dermatol 136: 598-600

4. Salerni G et al (2014) Dermatoscopic pattern of digital mucous cyst: report of three cases. Dermatol Pract Concept 4: 65-67

5. Schmoeckel C et al (2000) Dorsal mucoid cyst--ganglion-like pseudocyst of the joint space. dermatologist 51:682-684