A ganglion cyst is a common, non-cancerous lump that typically develops near joints or tendons. While they can appear in various parts of the body, these benign formations are frequently observed in the hands and wrists.
Understanding Ganglion Cysts
A ganglion cyst forms as a sac-like swelling filled with a jelly-like fluid, often emerging close to joints or tendon sheaths. These cysts are most frequently found on the wrist, both on the back (dorsal) and palm (volar) sides, as well as on the ankles, feet, and fingers. They typically appear as smooth, firm lumps, though their size can fluctuate, sometimes growing larger with activity and shrinking with rest. While ganglion cysts can affect individuals of any age, they are more commonly observed in women.
The Fluid Inside a Ganglion Cyst
The fluid contained within a ganglion cyst is a thick, clear, gelatinous substance, similar to synovial fluid that lubricates joints and tendons. This fluid is believed to accumulate due to a “one-way valve” mechanism, where synovial fluid leaks from a joint capsule or tendon sheath but cannot easily flow back. The fluid itself is sterile and does not pose a direct threat to health.
Causes and Accompanying Symptoms
The exact reason why ganglion cysts form is not fully understood, but factors like irritation to a joint or tendon, repetitive stress, minor trauma, or degenerative changes may contribute. For instance, gymnasts, who place repeated stress on their wrists, often develop these cysts. While many ganglion cysts are asymptomatic, some individuals experience symptoms. Pain is a common complaint, varying from mild to severe, often worsening with activity or pressure on the cyst. Other symptoms include tenderness, weakness in the affected limb, or numbness or tingling if the cyst presses on a nearby nerve.
Diagnosis and Treatment
Diagnosing a ganglion cyst typically begins with a physical examination, where a healthcare provider assesses the lump’s appearance, location, and texture. A common diagnostic technique involves transillumination, where a light is shone through the lump to confirm its fluid-filled nature. Imaging tests, such as ultrasound, can further confirm the presence of fluid and help differentiate the cyst from other masses. Magnetic resonance imaging (MRI) may be used for more detailed imaging, particularly if there is concern about nerve involvement or to rule out other conditions.
Treatment options for ganglion cysts vary depending on the symptoms and the cyst’s impact on daily life. For asymptomatic cysts, observation is often recommended, as many resolve spontaneously. If the cyst causes pain or functional limitations, aspiration, which involves draining the fluid with a needle, may be performed. However, recurrence is common after aspiration because the cyst wall remains.
Surgical excision, which removes the entire cyst and its stalk, offers a lower recurrence rate but is a more invasive procedure. The choice of treatment depends on individual symptoms, the cyst’s location, and patient preferences.