Ganglion cysts

A ganglion grows from a joint or a tendon sheath, and the jelly-like fluid inside it is a thicker form of the fluid that lubricates them. How it forms is not fully understood; repeated small strains to the area are the likeliest explanation.

Most appear for no clear reason. Now and then one follows an injury, or comes from a joint where arthritis is starting. They are much commoner in women than in men. There are four usual places in the hand and wrist:

• The back of the wrist, in the middle, the commonest, with about seven in ten, usually in young adults
• The front of the wrist at the base of the thumb, in young adults, or with wrist arthritis in older people; it often sits close to the artery where the pulse is felt
• The base of a finger on the palm side, a firm lump like a dried pea on the tendon sheath that hurts when you grip
• The back of a finger's end joint, in middle-aged or older people, with early osteoarthritis of that joint; it can press a groove into the nail

Ganglions also appear on the top of the foot.

The lump may be the only sign:

• A smooth, soft or firm, rounded lump under the skin, from smaller than a pea to a few centimetres across
• A lump that changes size, and may vanish and return
• Usually no pain, though some ache or hurt during or after moving the joint, or limit its movement
• Sometimes pain, numbness or tingling, where the cyst lies next to or presses on a nerve, which at the front of the wrist can bring on carpal tunnel syndrome

The diagnosis is usually straightforward from the lump's look, feel and place: smooth and round, varying in size, and it may let light through when a torch is held against it. When there is any doubt, a scan can show what the lump is.

Ultrasound in the clinic, done by Dr Borukhson, can confirm a simple sac of fluid, trace where it arises and help tell it from other kinds of lump, and it can guide the needle if the cyst is to be drained; the ultrasound clinic page describes the scan.

A ganglion is harmless, and leaving one alone has no long-term consequences. Most need no treatment beyond an explanation and time, and many disappear by themselves. When one causes trouble, the options depend on where it is and what it is doing:

• Waiting, with a wrist support or a compression wrap for comfort if it aches when you use the hand, and a simple painkiller if needed
• Draining it with a needle (aspiration), under local anaesthetic. A ganglion on the back of the wrist often refills afterwards; one on the tendon sheath at the base of a finger can disperse after a fine needle punctures it, and fewer than half come back. At the front of the wrist the artery is often close, which is one reason to drain it under ultrasound guidance
• A steroid injection to reduce swelling is another option
• An operation to remove it, which makes a return less likely: about one in ten for a ganglion on the back of the wrist or a finger's end joint, nearer three in ten at the front of the wrist. It leaves a scar and can bring lasting pain, stiffness or a nerve branch trapped in the scar, so many surgeons advise against it for a front-of-wrist ganglion and keep it for cysts that keep causing trouble

You and Dr Borukhson settle the plan together.

A painless ganglion that is not in your way needs nothing from you, and it is fine to let it be:

• Do not try to burst it or hit it; that risks an infection or damage to the skin, and even when it works there is a high chance of it coming back
• If it aches with a particular task, ease off that task for a while, and try a wrist support or a compression wrap
• Note its size now and then, so you can tell whether it is growing

A ganglion that comes back after it has gone, or is drained and refills, is behaving as ganglions do and is no sign that anything is wrong.

A ganglion is harmless, and most lumps are for a GP or a booked assessment. Some problems call for more, and the lists below set out a route for each, for example a lump that turns very painful, hot or red, a hurt wrist or hand, a hand or arm that weakens or goes numb without warning, a feverish illness that may be sepsis, and tingling that arrives with neck pain.

Treat any of these as a 999 or A&E emergency: call 999 and do not drive yourself to A&E.

• Severe illness with suspected sepsis: a high fever with shaking, confusion, rapid breathing, or feeling dramatically worse over hours
• With a fever or feeling unwell, a rash that does not fade when you press it, a stiff neck with eyes that cannot bear bright light, or skin, lips or tongue turning blue, grey, pale or blotchy, since these can be signs of meningitis or sepsis; on black or brown skin the rash and the change of colour may be easier to see on the palms of the hands or the soles of the feet
• A joint you cannot put weight on or move, or that has moved out of place, or, after a fall or injury, very bad pain or any tingling or numbness
• After an injury, a crack heard as it happened, or skin around it that has turned blue, grey or cold, since these can be signs of a broken bone
• Sudden weakness or numbness on one side, a drooping face or difficulty speaking, a sudden severe headache, sudden confusion or a seizure, or sudden loss of vision, any of which can be a stroke, even if it stops after a short time, and a hand or an arm that has suddenly gone weak or numb, with no injury behind it, is one of these signs
• An eye that suddenly and completely loses its sight
• Lips, mouth, throat or tongue that suddenly swell, a throat that feels tight, very fast breathing or a struggle to breathe or to swallow, skin, tongue or lips turning blue, grey or pale (on black or brown skin this may be easier to see on the palms of the hands or the soles of the feet), becoming suddenly very confused, drowsy or dizzy, or fainting and not being able to be woken, since this can be a severe allergic reaction, anaphylaxis, which can follow a dose of any medicine

Any of these needs an assessment that is urgent, on the same day, from your GP or NHS 111:

• A joint that is hot and swollen, with a fever or feeling unwell, since an infected joint has to be ruled out at once, at A&E or through NHS 111
• A joint that has become hot and very swollen suddenly, or is worsening quickly, even without a fever, since an infected joint does not always announce itself with one
• Joint pain with a fever, or feeling hot, cold or shivery, or generally unwell, since an infection in or around a joint has to be found the same day
• A lump, a finger or the palm that has turned very painful, hot or red, or hand pain with feeling hot, cold or shivery, since an infection in the hand can show itself this way and has to be found the same day, at A&E or through NHS 111 if a fever comes with it or you feel ill, short of the signs that follow; a lump, or the skin of a finger or the palm, turned hot or red, with a very high temperature or feeling hot, cold or shivery, a fast heartbeat or fast breathing, purple patches on the skin, which may be less obvious on black or brown skin, feeling dizzy or faint, confusion, or skin that is cold, clammy or pale, is a 999 or A&E emergency: call 999 and do not drive yourself to A&E
• Tingling in a hand, or numbness or weakness there that has come on gradually, with neck pain, since a nerve trapped at the neck can bring it on, and seeing someone that day tells it apart from pressure on the spinal cord, as our neck pain guide explains

See a GP if a lump worries you, and within days if it is growing, or feels hard and fixed in place, since a lump that goes on enlarging needs a scan to be sure it is a ganglion and nothing else. If you have diabetes, see a GP about a lump or a hand that troubles you whatever the timescale, since diabetes can make a hand problem more serious. Numbness or tingling in the hand that comes and goes, with no injury and no neck pain, is for a GP; numbness that has become constant, a habit of dropping things, a hand slowly losing its strength or a thumb whose fleshy base is thinning needs a GP within days, since the cyst may be pressing on a nerve. Hands that take more than half an hour to loosen up in the morning, a finger swollen from one end to the other, or a warm, swollen, stiff wrist should be seen by a GP within days, since an inflammatory arthritis can start in this way. Alongside neck pain, the nerve signs belong with the same-day list, and numbness or weakness that arrives suddenly, or numbness after a knock or fall, with the first. No referral is needed to be seen here; next-working-day appointments can almost always be arranged, and same-day appointments are sometimes possible. A wrist or hand at a strange angle or changed in shape after it was hurt, a finger pointing at an odd angle after an injury, or a cut that shows bone, is a 999 or A&E emergency; for an injury to the wrist or hand that might have broken a bone, without any of those or any sign from the first list, NHS 111 can say whether you need an X-ray. If you cannot tell how urgent something is, asking is never a mistake.

Most lumps of this kind turn out to be a harmless ganglion, and a scan can help show that it is one. An assessment can confirm what the lump is, pick out the rare one that needs more, and talk through whether waiting, drainage or removal makes sense. If a lump near your wrist or hand is bothering you, it is worth having it looked at.

How do you know it is a ganglion?

Usually by its look and feel: a smooth, round lump in one of the typical places, which may change in size and may let light shine through it. If there is any doubt, a scan helps: an ultrasound, usually done in the same appointment, can show whether it is a simple sac of fluid and where it springs from.

Will a ganglion go away by itself?

Often, yes. Many ganglions shrink and disappear on their own, though it can take from several months to a year, and leaving one alone does no harm. If it hurts when you use the hand, a wrist support can help while you wait. See a GP if the lump worries you, and within days if it is growing, or feels hard and fixed in place.

Should I try to burst it?

No. Trying to burst or pop a ganglion, by pressing hard on it or hitting it, can cause an infection or damage the skin, and even when it works there is a high chance of the cyst coming back. If one is bothering you, it can be drained with a needle or removed.

What happens if it is drained or removed?

Draining the fluid with a needle, under local anaesthetic, can shrink the lump, though a ganglion on the back of the wrist often refills; one at the base of a finger can disperse for good. An operation to remove the cyst lowers the chance of it coming back, to about one in ten at the back of the wrist and nearer three in ten at the front, but it can leave lasting pain, a scar, stiffness or tender nerve endings, so it is kept for cysts that keep causing trouble.

When should a lump near the wrist or hand be seen quickly?

A lump turned hot or red, with a very high temperature or feeling hot, cold or shivery, a fast heartbeat or fast breathing, purple patches on the skin, which may be less obvious on black or brown skin, feeling dizzy or faint, confusion, or skin that is cold, clammy or pale, is a 999 or A&E emergency, as the second list under When to seek help says. Call 999 and do not drive yourself to A&E. Short of those signs, a lump that turns very painful, hot or red, which may be infected, needs the same day: an urgent GP appointment or NHS 111, and A&E or NHS 111 if a fever comes with it or you feel ill; redness can be harder to see on brown and black skin. A lump that keeps growing, or feels hard and fixed, needs a GP within days.