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Jai Ganesh

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Ganglion cysts

Ganglion cysts

Gist

A ganglion arises out of a joint, like a balloon on a stalk. It grows out of the tissues surrounding a joint, such as ligaments, tendon sheaths, and joint linings. Inside the balloon is a thick, slippery fluid, similar to the fluid that lubricates your joints.

Ganglion cysts are lumps that most often appear along the tendons or joints of wrists or hands. They also can occur in ankles and feet. Ganglion cysts are typically round or oval and are filled with a jellylike fluid. They are not cancer.

Summary

A ganglion cyst is a small sac of fluid that forms over a joint or tendon (tissue that connects muscle to bone). Inside the cyst is a thick, sticky, clear, colorless, jellylike material. Depending on the size, cysts may feel firm or spongy.

Ganglion cysts, also known as Bible cysts, most commonly show up on the back of the hand at the wrist joint but can also develop on the palm side of the wrist. They can also show up in other areas, but those are less common.

Ganglion Cyst Symptoms

Most ganglion cysts show up as a soft bump or mass that changes size but doesn’t move. They're often painless. Swelling may appear over time or suddenly. Other symptoms of a ganglion cyst include:

* A bump that goes away and comes back
* One large cyst or many smaller cysts
* Some degree of pain, especially after an injury or trauma from repeated movement
* Long-lasting pain that gets worse when you move the affected joint
* Pressure on nerves that causes tingling or numbness
* Weakness in the affected finger if the cyst is connected to a tendon

Types of Ganglion Cysts:

* Ganglion cyst on the wrist

Ganglion cysts on the back of the wrist are more common in young adults and usually disappear without treatment. Ganglion cysts on the front of the wrist usually show up in younger people or older people with arthritis.

* Ganglion cyst on a finger

These cysts are usually found on the fingertip, just below the cuticle, where they're called mucous cysts. These are more common in people who are middle-aged or older.

* Ganglion cyst on the thumb

These cysts are rarer than those on the fingers. They can cause thumb triggering -- locking or catching when you move your thumb -- as well as pain and stiffness in the joint.

* Ganglion cyst on an elbow

Ganglion cysts on the elbows are rare but can happen. They can restrict joint movement and cause pain that comes and goes.

* Ganglion cyst on a foot

Ganglion cysts can grow on the top of your foot or on your ankle. These usually result from bone spurs (bony outgrowths) or from damage to joints or tendons caused by arthritis.

* Volar ganglion cyst

A volar ganglion cyst shows up as a pea-sized bump on the palm of your hand or at the base of your finger. These cysts can cause pain when you grip objects. Volar ganglion cysts tend to appear suddenly and don't get bigger or smaller. About half of the time, they disappear without treatment.

Ganglion Cyst Causes

Doctors don't know exactly what causes ganglion cysts. Injury or damage may cause the tissue of the joint to break down, forming small cysts that later create a larger mass. A flaw in the joint capsule or tendon sheath (layers of connective tissue that allow tendons to move smoothly over bones) also may cause the joint tissue to bulge.

Details

A ganglion cyst is a fluid-filled bump associated with a joint or tendon sheath. It most often occurs at the back of the wrist, followed by the front of the wrist.

The cause is unknown. The underlying mechanism is believed to involve an outpouching of the synovial membrane. Diagnosis is typically based on examination. The ability to shine through the bump or any past decrease in size supports the diagnosis of the bump as a ganglion cyst. Ganglion cysts are usually obvious upon observation. Medical imaging may be considered on infrequent occasions to rule out another diagnosis.

Treatment is not necessary. Options for treatment include needle aspiration or surgery. About half the time, they resolve on their own. About three per 10,000 people newly develop ganglion of the wrist or hand a year.

Presentation

The average size of these cysts is 2 centimetres (0.79 in), but excised cysts of more than 5 centimetres (2.0 in) have been reported. The size of the cyst may vary over time. Between 50 and 70% of all masses on the hand and wrist are ganglion cysts.

Wrist

They commonly are found near the wrist joint, especially at the scapholunate area.

Common wrist ganglions include:

* dorsal wrist ganglion
* volar wrist ganglion
* extensor retinaculum ganglion
* occult ganglion
* intraosseous ganglion
* mucous cyst

Foot

In a 2007 study of patients in Glasgow whose foot lumps were removed surgically, 39 of 101 cases were ganglion cysts. The study replicated earlier findings that no ganglion cysts were found on the sole or heel. The authors wrote, "Although lumps in these areas may be ganglia, the surgeon should probably consider other diagnoses in the first instance." The researchers noted a preponderance of occurrence among females (85%) and that 11 of the other cases had been misdiagnosed as ganglion cysts before surgery.

Ganglion cysts are not limited to the hands and feet. They may occur near the knee, commonly near the cruciate ligaments, but they may occur at the origins of the gastrocnemius tendon, and anteriorly on Hoffa's infrapatellar fat pad. At the shoulder, they typically occur at the acromioclavicular joint or along the biceps tendon.

Other

From their common origin at a joint or tendon, ganglion cysts may form in a wide range of locations. Rarely, intraosseous ganglion cysts occur, sometimes in combination with a cyst in the overlying soft tissue. Rare cases of intramuscular ganglion cysts in the gastrocnemius muscle of the calf have been reported. It is possible for a cyst to be considerably displaced from the joint. In one extreme case, a ganglion cyst was observed to propagate extensively via the conduit of the common peroneal nerve sheath to a location in the thigh; in such cases surgery to the proximal joint to remove the articular connection may remove the need for a riskier, more extensive surgery in the neural tissue of the thigh. The cysts may intrude into the spine, which may cause pain and dysesthesia in distant extremities.

Cystic adventitial disease, in which a cyst occurs within the popliteal artery near the knee, has been proposed recently to occur by an articular mechanism, with a conduit leading from the joint, similar to the development of ganglion cysts, that spreads within the peroneal nerve.

Cysts that were compressing one or more nerves and causing bone erosions have been reported to occur near the shoulder joint.

Causes

The most commonly accepted probable cause of ganglion cysts is the herniation hypothesis, by which they are thought to occur as an out-pouching or distention of a weakened portion of a joint capsule or tendon sheath. This description is based on the observations that the cysts occur close to tendons and joints. The microscopic anatomy of the cyst resembles that of tenosynovial tissue. The fluid is similar in composition to synovial fluid. Dye injected into the joint frequently ends up in the cyst. Dye injected into the cyst rarely enters the joint, however, which has been attributed to the apparent formation of an effective and one-way "check valve", allowing fluid out of the joint, but not back in.

In synovials, post-traumatic degeneration of connective tissue and inflammation have been considered as causes. Other possible mechanisms for the development of ganglion cysts include repeated mechanical stress, facet arthrosis, myxoid degeneration of periarticular fibrous tissues and liquefaction with chronic damage, increased production of hyaluronic acid by fibroblasts, and a proliferation of mesenchymal cells.

Diagnosis

Ganglion cysts are diagnosed easily, as they are visible and pliable to touch.

Ultrasonography (US) may be used to increase diagnostic confidence in clinically suspected lesions or to view smaller "occult" cysts as a cause of dorsal wrist pain with forceful extension.

Treatment

At least 33% resolve without treatment within six years, and 50% within 10 years.

Surgical excision is the primary discretionary, elective treatment option for ganglion cysts. Alternatively, a hypodermic needle may be used to drain the fluid from the cyst (via aspiration). The recurrence rate is about 50% following aspiration of a ganglion cyst.

Complications

Complications of treatment may include joint stiffness and scar formation. Recurrence of the lesion is more common following excision of a volar ganglion cyst in the wrist. Incomplete excision that fails to include the stalk or pedicle also may lead to recurrence, as will failing to execute a layered closure of the incision.

Prognosis

Recurrence rate is higher in aspirated cysts than in excised ones. Ganglion cysts have been found to recur following surgery in 12% to 41% of patients.

A six-year outcome study of the treatment of ganglion cysts on the dorsal wrist compared excision, aspiration, and no treatment. Neither excision nor aspiration provided long-term benefit better than no treatment. Of the untreated ganglion cysts, 58% resolved spontaneously; the postsurgery recurrence rate in this study was 39%. A similar study in 2003 of ganglion cysts occurring on the palmar surface of the wrist states: "At 2- and 5-year follow-up, regardless of treatment, no difference in symptoms was found, regardless of whether the palmar wrist ganglion was excised, aspirated, or left alone."

Additional Information

A ganglion cyst is a round, fluid-filled lump of tissue that usually appears along tendons or joints. It typically occurs on the wrist or hand, but it can also appear on the ankle or foot.

Ganglion cysts range in size. They can be as small as a pea or as large as a golf ball. They can also be soft or firm. Some cysts are visible underneath the skin, but others are so small that you can’t see them.

These types of cysts are common and usually harmless. They aren’t cancerous. Most go away without treatment.

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