ConditionBones, joints & muscles
Ganglion Cyst
A ganglion cyst is a noncancerous, fluid-filled lump that grows from a joint or tendon sheath, most often on the back of the wrist, the palm side of the wrist, the base of a finger or the top of the foot. It is filled with thick, jelly-like fluid and can change size or disappear on its own. Many are painless and need no treatment. If a cyst hurts, presses on a nerve or limits movement, it can be drained with a needle or removed surgically, though it may come back.
Also called: Ganglion, wrist ganglion, bible cyst, synovial cyst, mucous cyst (at the finger end joint)
At a glance
- What it is
- A benign sac of thick joint fluid attached to a joint or tendon sheath.
- Where
- Back of the wrist (most common), palm side of the wrist, base of fingers, finger end joints, top of the foot and ankle.
- Symptoms
- A smooth lump, sometimes aching, especially with wrist movement. It can change size.
- Course
- Many shrink or disappear without treatment.
- Treatment
- Observation, splinting, needle aspiration or surgical removal.
When to get help
See a doctor within a day or two
- A lump that becomes red, hot and painful, especially with fever (possible infection)
- A lump with new numbness, tingling or weakness in the hand or fingers
Book a routine appointment
- A wrist, hand or foot lump that is painful or interferes with activities
- A lump that is hard, fixed, growing quickly, or larger than about 5 cm (2 inches)
- A cyst at the finger end joint that drains fluid or distorts the nail
- Any lump where the diagnosis is uncertain
Usually safe to manage at home
- A smooth, soft, painless lump on the wrist or hand that has been stable or changes size, without numbness or weakness
What a ganglion cyst is
Joints and tendons are lined by a membrane that makes lubricating fluid. A ganglion cyst forms when this fluid leaks out and collects in a sac, connected to the joint or tendon sheath by a stalk that acts like a one-way valve. The fluid is thick and clear, similar to jelly. Ganglion cysts are not cancer and do not spread.
Common locations
| Location | Notes |
|---|---|
| Back of the wrist (dorsal) | Most common, often more visible when the wrist bends forward |
| Palm side of the wrist (volar) | Near the radial artery at the base of the thumb, so care is needed with aspiration or surgery |
| Base of a finger (flexor sheath) | Small, firm, pea-sized lump in the palm that can be tender when gripping |
| Finger end joint (mucous cyst) | Linked to osteoarthritis of that joint, often with a groove in the nail |
| Top of the foot and ankle | Can rub on shoes |
| Knee | Often linked to meniscus tears, sometimes called parameniscal cysts |
Causes and risk factors
The exact cause is unknown. Contributing factors include:
- Age and sex: most common between ages 15 and 40 and in women
- Joint or tendon irritation: repetitive use, such as in gymnasts
- Previous injury to the joint
- Osteoarthritis: especially for mucous cysts at the finger end joints
Symptoms
- A visible, smooth, round or oval lump, usually 1 to 3 cm (under 1 inch)
- Firm or rubbery to the touch, may feel soft when pressed
- Often painless, but can ache, especially with movement
- Size that varies, often bigger with activity and smaller with rest
- If pressing on a nerve: tingling, numbness, weakness or pain in the hand or fingers
- On the foot: discomfort from shoe pressure
Diagnosis
- Examination: the doctor checks the lump's location, feel and tenderness. Shining a light through it (transillumination) often shows that it is fluid-filled.
- X-ray: to look for arthritis or bone problems.
- Ultrasound or MRI: confirm the lump is a fluid-filled cyst and find hidden (occult) ganglions that cause wrist pain without a visible lump.
- Aspiration: drawing out the thick jelly-like fluid with a needle confirms the diagnosis.
Other lumps that can look similar
Lipomas, giant cell tumors of the tendon sheath, bony outgrowths from arthritis, rheumatoid nodules and rarely other tumors. A lump that is hard, fixed, growing quickly or painful at rest should be imaged.
Treatment
Observation
If the cyst is painless and not affecting function, no treatment is needed. Many ganglion cysts get smaller or disappear over months to years.
Rest and splinting
A wrist splint can reduce activity-related pain and may shrink the cyst by limiting fluid production. Long-term immobilization is not recommended, because it weakens the muscles.
Aspiration
The doctor numbs the area, draws out the fluid with a needle, and sometimes injects a steroid. It is quick and avoids surgery, but cysts often come back, with recurrence rates of around half or more in many studies.
Surgery
Surgical removal (excision) of the cyst and its stalk, either through an open incision or keyhole (arthroscopic) surgery, is recommended for painful or recurrent cysts or those causing nerve symptoms. Recurrence is less common after surgery than after aspiration, though it can still happen. Recovery usually takes 2 to 6 weeks. Possible complications include stiffness, scar tenderness and nerve or blood vessel injury.
What not to do
Do not try to burst a ganglion cyst by hitting it with a heavy object (the traditional "bible cyst" treatment) or puncturing it yourself. This can injure the hand and cause infection, and the cyst often returns.
Outlook
Ganglion cysts are harmless. Many go away without treatment. Those that are treated may come back, but repeat treatment is usually effective.
Frequently asked questions
What causes a ganglion cyst?
The exact cause is unknown. Fluid leaks from a joint or tendon sheath and collects in a sac. They are more common in women aged 15 to 40, after joint injuries, with repetitive wrist use, and with arthritis of the finger joints.
Does a ganglion cyst go away on its own?
Often, yes. Many ganglion cysts shrink or disappear without treatment over months to years. If the cyst is painless and not affecting your hand or foot, it is reasonable to watch it. Treatment is for pain, nerve symptoms or limited movement.
Should I pop a ganglion cyst?
No. Hitting it with a heavy object or puncturing it yourself can injure your hand, cause infection and usually does not stop the cyst coming back. A doctor can drain it safely with a needle under sterile conditions if treatment is needed.
Is a ganglion cyst dangerous?
No. Ganglion cysts are benign and do not turn into cancer. They can cause pain or press on nerves, which may need treatment. A lump that is hard, fixed, growing quickly or causing constant pain should be checked to rule out other causes.
Will a ganglion cyst come back after removal?
It can. Recurrence is common after needle aspiration, often in about half of cases. Surgical removal of the cyst with its stalk has a lower recurrence rate, but cysts still return in some people.
Sources
This guide was written from current patient and clinical guidance, including:
- American Academy of Orthopaedic Surgeons (OrthoInfo): Ganglion cyst of the wrist and hand
- American Society for Surgery of the Hand: Ganglion cysts
- MedlinePlus: Ganglion cyst
- NHS: Ganglion cyst
- Mayo Clinic: Ganglion cyst, symptoms and causes