The patient is concerned about a rubbery, rounded swelling most commonly emerging from the dorsal or volar aspect of the wrist or the flexor tendon sheath of the hand. It may have appeared abruptly, been present for years, or fluctuated, suddenly resolving and gradually returning in pretty much the same place. The patient often first notices it when a minor injury brings it to their attention and frightens them. There is usually little tenderness, inflammation, or interference with function, but ganglion cysts may be bothersome with symptoms that include pain, paresthesias, limitation of motion, or weakness. Often, the patient is only disturbed by its unsightly appearance.
What To Do:
Take a thorough history and physical examination of the hand to ascertain that everything else is normal. These cysts are usually self-evident and generally no larger than 2 cm in diameter. They are soft and ballotable and appear on the dorsal or volar aspect of the wrist.
It is unnecessary to obtain a radiograph of a classic, asymptomatic ganglion cyst. Standard radiographs will not demonstrate the cyst and need only be obtained when the cyst is symptomatic and there is a question of underlying bony disease or injury.
Although most ganglions can be diagnosed easily on physical examination, ultrasonography may be helpful in diagnosing a small or questionable lesion. Transillumination with an otoscope light will demonstrate its clear cystic nature.
Explain to the patient that this is a fluid-filled cyst, spontaneously arising from bursa, ligament, or tendon sheath and poses no particular danger. Treatment options include the following: (1) doing nothing; (2) draining the contents of the cyst with an 18- or 22-gauge needle to reduce its size, with or without injecting it afterward with a corticosteroid; or (3) arranging for a surgical excision, which will provide a definitive pathologic diagnosis.
Most ganglia resolve spontaneously and do not require treatment.
If the patient has symptoms, including pain or paresthesias, or is disturbed by the appearance, aspiration with or without injection of a corticosteroid is effective, without recurrence, in 27% to 67% of patients. Surgical treatment involves total ganglionectomy, with removal of a modest portion of the attached capsule. Recurrence after surgical treatment is between 5% and 15%.
Follow the wishes of the patient regarding treatment, and arrange for follow-up.
If the patient requests immediate decompression, prepare the skin and anesthetize the skin and cyst wall using a 30-gauge needle with 1% lidocaine. With an 18- or 22-gauge needle on a 10-mL syringe, aspirate the mucinous contents. Optionally, instill a long-acting corticosteroid, such as 1 mL betamethasone (Celestone Soluspan) or 10 to 20 mg of triamcinolone (Kenalog-10), along with 2 mL of 0.25% or 0.5% bupivacaine (Marcaine). When injecting a corticosteroid after aspiration, a hemostat is used to stabilize the needle while the syringe is changed.
Provide appropriate follow-up care.
What Not To Do:
Do not ignore a cyst that drains spontaneously. With external drainage, there is the risk for developing a serious joint or soft tissue infection.
Ganglion cysts are outpouchings of bursae, ligament, or tendon sheaths, with no clear cause and no relation to nerve ganglia. Perhaps ganglion cysts got their name because their contents are like “glue.”
Ganglion cysts may be caused by trauma or tissue irritation when modified synovial cells lining the synovial-capsular interface are stimulated to produce mucin. This mucin dissects along the attached joint ligament and capsule to form capsular ducts and dilatations (lakes) of mucin. The ducts and lakes of mucin coalesce to form a solitary ganglion cyst. Their viscous mucin consists of hyaluronic acid, albumin, globulin, and glucosamine.
Dorsal wrist ganglia represent 60% to 70% of all ganglia. Twenty percent of all ganglia occur in the volar wrist. The flexor tendon sheath of the fingers is involved in 10% to 12% of ganglia.
A dorsally located ganglion of the distal interphalangeal joint is also known as a mucous cyst. Reassurance about their insignificance is often the best we can offer patients.