Sciatica

Sciatica is pain that runs from the lower back or the buttock down the leg because the sciatic nerve is irritated or compressed. The word sounds like a diagnosis, but it is really a description: the nerve itself is not at fault, something is pressing on it, most often a bulging disc in the spine. The first thing worth knowing is that in most people it settles on its own within a few weeks, and that what you do during those weeks affects the timescale far more than any tablet. This page also sets out separately the signs that cannot wait even a day — there are only a few, but everyone should know them.

How to recognise it

Sciatica is nearly always one-sided. The pain starts in the lower back or straight in the buttock and travels down the back or outer side of the thigh, below the knee, often as far as the calf, foot and toes. People describe it differently: burning, shooting, like an electric shock, like a tight wire. It can come on suddenly with an awkward movement or a heavy lift, or build up over several days.

Along with the pain there is usually something from this list:

• tingling and pins and needles along the line of the pain;
• numbness in a patch of skin on the calf or foot;
• a feeling that the leg has lost strength;
• pain that gets worse when you cough, sneeze or strain — a very characteristic sign;
• pain that makes sitting for more than a few minutes difficult but eases once you stand up and walk.

A useful dividing line: if only your back hurts and nothing travels down the leg, this is most likely ordinary back pain rather than sciatica — a different condition, both in its causes and in how it behaves. And the other way round: in sciatica the leg pain is usually worse than the back pain, and many people do not complain of their back at all.

What presses on the nerve is most often a herniated disc: the jelly-like centre of the disc pushes out and catches the nerve root. Less often it is narrowing of the spinal canal, which makes the leg start hurting after a few minutes of walking and eases as soon as you sit or lean forwards; a slipped vertebra; or the after-effects of an injury.

What to do in the first few weeks

Everything here rests on one fact: sciatica settles on its own in the great majority of cases. Clear improvement usually comes within four to six weeks, and for most people it is over within three months. Not because the disc goes back into place, but because it gradually shrinks and the inflammation around the nerve root dies down.

Hence the main practical conclusion, which runs against habit: lying down is not a treatment. Bed rest for sciatica does not speed recovery up, it slows it down: muscles weaken, joints stiffen and the pain of being still gets worse. Moving hurts, but it does no harm.

• Carry on with normal life as far as you can. Walk, get up every twenty or thirty minutes if you work sitting down, get outdoors.
• Judge how much to do by the rule "uncomfortable but bearable, and no worse tomorrow". Walking, swimming and simple stretching and strengthening exercises suit almost everyone; heavy lifting and sharp twisting during the acute phase do not.
• Heat over the lower back and buttock helps many people: a hot water bottle, a warm bath, a shower. Some people find cold better. The right choice is whichever eases things for you.
• Sleeping is easier on your side with a pillow between the knees, or on your back with a rolled towel under the knees; there is no need to buy a special mattress.

What to take for the pain

To be straight about it: painkillers work less well in sciatica than in other kinds of pain, and you should not expect them to take it away completely. Their job is more modest and more important — to make movement possible, without which recovery is slower.

• Paracetamol on its own does little for sciatica, though many people start with it.
• Anti-inflammatory medicines such as ibuprofen have a moderate effect, and not in everyone. They do not suit everybody: with stomach, kidney or heart problems, with raised blood pressure and in pregnancy they are only taken with a doctor's agreement.
• They are better taken as a short course alongside movement, rather than "until it goes away".

What not to do: press for gabapentin or pregabalin "for nerve pain" — in sciatica they have not proved useful, and they do have side effects; ask for strong opioid painkillers to treat yourself at home; wear a back brace for weeks. If you cannot walk or sleep without painkillers, that is a reason to see a doctor rather than to increase the dose yourself.

When it is a matter of hours

There is one complication this section exists for. The bundle of nerves at the very bottom of the spine is called the cauda equina, and if that bundle is compressed rather than a single root, the bladder, the bowel and both legs are affected at once. This is an emergency: without surgery within hours, the loss of bladder control and sensation becomes permanent.

Call an ambulance immediately or go straight to hospital if even one of the following appears:

• numbness in the perineum, around the back passage and genitals, and on the inner thighs — the area that touches a bicycle saddle. It may feel like "I cannot feel the toilet paper";
• being unable to pass urine, feeling a full bladder without any urge, or the opposite: urine leaking without you noticing;
• loss of bowel control or loss of the urge to open your bowels;
• weakness or numbness in both legs at once, especially if it is increasing, or pain that has spread from one leg to both.

Do not wait for morning, do not wait for an appointment, do not see whether it settles by evening. Do not drive in this state — ask someone to take you, or call an ambulance, in European countries on the single number 112. Take a list of your medicines with you. Say plainly that you have numbness in the perineum and trouble passing urine: those words determine how quickly you are seen.

Other reasons not to wait

Besides the cauda equina there are signs that need a doctor the same day or the next, not after a month of watching and waiting.

• The foot has stopped lifting. The toes catch on the floor, you have to raise the knee higher to walk, and the front of the foot slaps down. This is not a leg that has "gone to sleep": it is loss of function in a nerve root, and the sooner it is freed the better the chance of full strength returning.
• Weakness in the leg that increases day by day. Getting out of a chair, climbing stairs or standing on tiptoe has become hard.
• Fever together with back pain, particularly with shivering, night sweats, a weakened immune system, or after recent spinal surgery or injections. This is how a spinal infection or an abscess next to the spinal cord shows itself.
• Pain that began after a fall, a blow or a road accident, or after a minor injury in someone with osteoporosis or on long-term steroid treatment.
• Night pain that stops you sleeping and does not depend on position, together with weight loss, loss of appetite or a past cancer. This combination should always be raised with a doctor.

And the ordinary, unhurried reason to book an appointment: the pain has not begun to ease within four to six weeks, or it is stopping you working and sleeping, or the sciatica keeps coming back.

About MRI: why an early scan usually changes nothing

"Can I have an MRI" comes up in almost every consultation, and a refusal looks like cost-cutting. The real reason is different.

Huge numbers of people with no pain at all have findings on their scan. Scan the lower spine of a group of healthy people with not a single complaint and disc bulges turn up in about a third of those in their thirties and in most of those past fifty. It is an age-related change, like grey hair. So a hernia seen on a scan does not by itself prove that it is what hurts.

Second: in the first few weeks the result does not change the treatment. With a hernia or without one the plan is the same — movement, pain relief as needed, time. A scan is needed when a decision depends on it: there are warning signs from the sections above, or the pain has gone on for months and an injection or an operation is being considered.

Third, and less obvious: an early scan sometimes does harm. Someone who reads "disc protrusion, degenerative change, spondylosis" in a report starts protecting their back, moves less and recovers more slowly. This is well described and has a measurable effect on how long recovery takes.

An X-ray in sciatica shows neither the discs nor the nerves — it answers only the question of whether there is a fracture.

If the pain does not settle

When several weeks of self-help have not worked, a doctor will usually suggest the following.

• Sessions with a physiotherapist. Not passive treatments but a tailored exercise programme and a look at how you move, lift and sit. This is the best-supported part of treatment.
• A review of the pain relief. Sometimes a short course of other medicines is added, and that is worth doing with a doctor rather than on a friend's advice.
• A steroid injection next to the nerve root (an epidural injection). It does not help everyone and its effect lasts a limited time, but it can buy a respite and break the cycle of pain, stiffness and more pain. A sensible step before any talk of surgery.
• Surgery. It is discussed for severe pain that has resisted everything for months, for weakness that is getting worse, and for cauda equina syndrome, where it is urgent. Usually the part of the disc pressing on the root is removed. The honest picture is this: surgery relieves the leg pain sooner, but a year or two later the results in those operated on and those treated without surgery are much the same. So there is no need to rush in ordinary sciatica — and every need where there is weakness or bladder and bowel involvement.

Psychological support for long-lasting pain is not a hint that the pain is imagined: long pain changes sleep, mood and tolerance of effort, and working on that speeds the return to normal life.

How to lower the chance of it coming back

Sciatica tends to recur, and there is no way to guarantee against it. But a few things genuinely make a difference.

• Regular movement. The most reliable item on the list: walking, swimming, any exercise for the back and abdominal muscles that you will keep up for years rather than a month.
• Not sitting for hours on end. Getting up and walking about every half hour matters more than the perfect chair.
• Lifting from a squat, keeping the load close to you and not twisting as you lift.
• Excess weight adds load to the lower back; even a modest loss is noticeable.
• Stopping smoking: in people who smoke, episodes are more frequent and last longer.

And what not to count on: special cushions, belts and insoles, expensive mattresses and promises to "put the vertebra back" with a single movement. Most of them do no harm, but they do not protect against recurrence either.

Online consultation

A remote appointment settles the commonest question of the first few days: whether this is sciatica at all, whether anything you are feeling is a warning sign, and what to do today. The doctor will go through exactly how the pain travels and ask about passing urine and about strength in the leg and foot — that is, check precisely what separates an ordinary episode from an urgent one. It is also a convenient way to adjust pain relief around your other conditions, to come away with a clear plan of movement for the coming weeks, and to work out whether a scan is needed or would change nothing. And one very common request: to have an MRI report already done explained, because it usually sounds worse than it is. The signs in the cauda equina section are not assessed remotely — with those, go straight to hospital.

This material is for information only and does not replace medical advice.