Ganglion cysts (i.e., synovial cysts or ganglia) are the most common soft tissue tumors of the wrist and hand.1 They are a common reason for patients to present to the Emergency Department. The chief complaint is usually a mild pain or ache, exacerbated by movement, and localized to a 1 to 2 cm mass on the wrist or hand (Figures 130-1, 130-2, and 130-3). Patients may also present with concerns about a painless “lump.” Acute trauma prior to presentation is uncommon. Patients often give a history of repetitive motion at the site. The mass usually increases in size progressively over time or occasionally may grow rapidly over a short period. Patients presenting to the Emergency Department with ganglia may have already attempted one of several popular home remedies (e.g., homeopathic medications or striking the cyst firmly with a large book or hammer).
Oblique view of the wrist demonstrating a ganglion cyst overlying the scapholunate joint. (Used from James Heilman, MD at www.commons.wikimedia.org.)
Cross-section through the scapholunate joint demonstrating a ganglion cyst. The needle is inserted into the cyst cavity to aspirate its contents.
Aspiration of a ganglion cyst. A. The needle is inserted. B. Aspiration of the contents flattens the ganglion cyst. C. The aspirated ganglion cyst with the aspirated material on the slide.
Ganglion cyst aspiration is a relatively simple procedure that may be performed by the Emergency Physician. The practice of cyst aspiration has been challenged because of the high recurrence rates of up to and even greater than 50%.2-6 The procedure usually alleviates presenting symptoms, is occasionally curative, and is more cost-effective than referring all patients for surgical treatment.7
ANATOMY AND PATHOPHYSIOLOGY
Ganglia are synovial cysts that originate from a joint capsule or tendon sheath.8 They have no malignant potential. It is unclear whether ganglia are formed by herniation of the tendon sheath, myxomatous degeneration of connective tissue, or some other mechanism. Contained within the cyst is a viscous, jelly-like fluid. Ganglia often connect with the underlying synovial cavity or tendon sheath by a stalk (Figure 130-2). Hyaluronic acid makes up all or part of the mucoid fluid.9
Ganglia are usually encountered on the dorsum of the wrist, in particular over the scapholunate ligament (Figures 130-1, 130-2, and 130-3). They may also be found on the palmar surface of the wrist, ...