Ganglion cyst
A ganglion cyst is a mucin-filled swelling that herniates from a joint capsule or tendon sheath, most often on the dorsal wrist, diagnosed clinically by transillumination and managed with observation, aspiration with corticosteroid injection, or surgical excision for persistent or symptomatic cysts.
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What this article covers
- Overview
Benign synovial-lined cyst: a ganglion cyst is a fluid-filled swelling that arises from herniation of joint capsule or tendon sheath connective tissue, filled with thick mucinous fluid rather than true synovial fluid.
- Epidemiology
Common soft-tissue mass of the hand and wrist: ganglion cysts are the most frequent soft-tissue mass of the hand and wrist encountered in general and hand-surgery practice.
- Risk factors
Repetitive wrist use or trauma: activities and occupations with repetitive wrist flexion/extension or minor joint trauma are associated with cyst formation, though many arise without an identifiable trigger.
- Pathophysiology
Herniation of joint capsule or tendon sheath tissue: a defect in the dense connective tissue capsule allows synovial-lined tissue to herniate outward, forming a one-way valve.
- Clinical features
Slowly growing, painless (or mildly aching) mass overlying a joint or tendon sheath: most commonly the dorsal wrist; may wax and wane in size, including intermittent spontaneous disappearance.
- Differential diagnosis
Lipoma: soft, mobile, does not transilluminate, not fixed to underlying joint or tendon structures.
- Diagnosis
Clinical diagnosis confirmed by transillumination: the diagnosis is established at the bedside by the combination of a round, rubbery mass overlying a joint or tendon sheath that transilluminates…
- Management
First, for an asymptomatic or minimally symptomatic cyst: reassure the patient and manage with observation alone, since up to 50% of ganglion cysts spontaneously regress without any intervention.
- Complications
Nerve compression: a cyst adjacent to a peripheral nerve (tibial nerve at the tarsal tunnel, ulnar nerve at Guyon canal, or a digital nerve) can cause pain, paresthesia, or weakness requiring…
- Prognosis
Excellent: the great majority resolve or are cured with observation or excision, and the lesion is always benign.
- Prevention
No proven primary prevention: there is no established screening test, interval, or prophylactic medication because ganglion cysts arise sporadically from joint capsule or tendon sheath herniation without a modifiable single cause.
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