Ganglion Cyst
A
ganglion cyst is a firm fluid-filled lump that can suddenly or
gradually appear in various locations on the wrist or hand. The
most common location is on the back of the wrist.

Ganglion cysts may also appear on the palm side of the wrist, or at the base of a finger.
These
lumps may change in size from day to day, and may even disappear
spontaneously. They can be quite painful, but sometimes even
rather large cysts are completely painless. Many patients notice
that a cyst will enlarge temporarily after periods of increased
activity with the wrist or hand.
Sometimes a ganglion cyst
develops as a result of an injury, but more often there is no known
cause. The cyst feels firm, and often is mistaken for a "bone out
of place." However, the cyst is actually a balloon-like
structure, filled with fluid which arises from the joint or tendon
sheath underneath the cyst.
Although ganglion cysts may be
painful, they are usually harmless, even if untreated. They do
not become cancerous, and most are located where they will not put
pressure on any important nerves or blood vessels.
The doctor
can usually diagnose a ganglion cyst by examining it, but sometimes an
X-ray or sample of fluid from the cyst is needed to rule out other
problems.
Once the diagnosis is made, some patients choose to
leave a ganglion cyst untreated, if it is not painful or large enough
to be unsightly.
TREATMENT
If the cyst is painful, unsightly, or interfering with use of the hand, it can be treated with conservative or surgical means.
Conservative
treatment usually involves removal of fluid from the cyst with a
needle; while the needle is in place, a small amount of cortisone is
injected into the cyst. This method may cause the cyst to shrink,
to become painless, or even to disappear.
If the cyst remains
after conservative treatment, or the patient and doctor decide that
surgical treatment is needed, the cyst can be removed. For wrist
ganglion cysts, surgical removal is done under regional block
anesthesia (only the arm is numbed), as an outpatient. Even
though the lump seems to be "right under the skin," the cyst has an
attachment to the joint or tendon sheath underneath, and can be removed
most reliably and safely in the operating room, with the best chance of
permanent success.
A splint is generally worn for about 10 days
after surgery, following which mild activity restriction is advised for
another 10 days.