Back Pain and Sciatica

Sciatica is frightening in a way that ordinary back pain is not.

The pain is often worse. It goes somewhere it should not. It burns, or shoots, or feels electric. Bits of your leg go numb. It wakes you at three in the morning and there is no position that helps. And nearly everybody who gets it wonders whether a nerve is being permanently damaged.

So let me tell you the most important thing first. Sciatica is miserable, and it usually gets better. Even the ones that look worst on a scan usually get better.

This guide is not saying your pain is in your head. Your pain is completely real.

One thing before you start. Sciatica has one genuine emergency attached to it, and it is worth knowing the signs.

Read it in chunks. There is no test at the end.

The short version

• Pain is an alarm. It protects you. It does not measure damage.
• There is a gate in your spinal cord. It controls how much of the warning signal reaches your brain.
• Sciatica usually comes from an irritated nerve root, and irritation is mostly inflammation rather than crushing.
• Nerve pain feels alarming. Nerve pain is not the same as nerve damage.
• Herniated discs shrink on their own. The bigger and nastier they look, the more likely they are to shrink.
• Most people get substantially better over weeks to a few months, without surgery.
• Surgery gets some people there faster. By a year or two, the results are much the same.
• NICE advises against gabapentin, pregabalin, steroid tablets and diazepam for sciatica. See section 10.
• There is one emergency to know about. Section 16 tells you exactly what to watch for.

1. Pain is an alarm, not a damage meter

It feels obvious that pain comes from your back and leg. It does not, quite.

Your body has danger sensors. They fire when tissue is stretched, squashed, inflamed or irritated. They send warning signals to your spinal cord, and then to your brain. None of that is pain yet. It is just information.

Then your brain weighs that information against everything else it knows. What were you doing? What happened last time? What do you think this means? How stressed are you? Did you sleep?

Then it decides: how much danger am I in, and how much pain does this person need to feel to keep them safe?

Pain is the answer. Your brain produces it.

That is why damage and pain match up so badly:

• A paper cut really hurts. There is almost no damage.
• Soldiers get badly hurt and feel very little until they are safe.
• People who have lost a leg can still feel pain in it.

So how much pain you feel does not tell you how much damage there is. It tells you how protective your body is being right now.

2. The pain gate

In 1965, two researchers called Ronald Melzack and Patrick Wall came up with an idea that changed pain medicine. It is still one of the most useful pictures we have.

Picture a gate in your spinal cord. Warning signals have to pass through it to reach your brain.

When the gate is open, lots get through and you feel more pain. When it is closed, fewer get through and you feel less. Nothing in your back has changed. Only the gate has.

What closes the gate

• Touch, rubbing, heat and hands-on treatment. Touch signals travel on bigger, faster nerves than danger signals, and they crowd them out. It is why you rub your elbow after you bang it.
• Moving and exercise. They release your body's own painkillers.
• Feeling safe and calm.
• A decent night's sleep.
• Understanding what is going on. With sciatica this matters more than usual, because the fear of nerve damage is doing a lot of the work.

What opens the gate

• Stress and worry. Especially worrying that a nerve is being damaged.
• Broken sleep. Sciatica is very good at wrecking sleep, and then the broken sleep turns the pain up.
• Low mood, and feeling that nobody has listened.
• Testing the leg over and over to see how far it goes.
• Being afraid to bend or move.
• Being told frightening things about your spine.

Here is the key bit. Your brain does not just receive signals at that gate. It sends signals down and changes the settings.

3. When the alarm gets too sensitive

If your sciatica has been going on for months, this section matters.

When a pain system has been busy for a long time, it does not wear out. It gets better at its job. The sensors fire more easily. The spinal cord turns the signal up. The brain decides there is danger more quickly.

Think of a car alarm. When it was fitted, it went off if someone tried to force the door. Years later it goes off when a cat walks past.

The alarm is not broken. It is not lying. It is just set far too sensitive for the actual level of threat.

With long lasting sciatica, part of what you are feeling is often a sensitive system rather than an angry nerve. That matters, because a sensitive system can be calmed down. Your body learned it, so your body can unlearn it.

4. What sciatica actually is

Your sciatic nerve is about as thick as your finger. It is formed where several nerve roots leave your lower spine and join together. It runs through your buttock and down the back of your leg.

The word sciatica is a description, not a diagnosis. It means leg pain coming from an irritated nerve root. It does not tell you why.

The commonest reason is a disc. Part of the soft inner material pushes out through the tough outer ring and reaches a nerve root.

Here is the part most people are never told. It is mostly not about squashing. The material inside a disc is chemically irritating to a nerve. When it escapes, it inflames the nerve root it touches. That inflammation is doing much of the work, not the pressure.

That explains a lot:

• Why anti-inflammatory treatment can help.
• Why the pain settles as the inflammation settles, often long before the scan changes.
• Why some people have a large disc bulge sitting right on a nerve and no symptoms at all.

Not all leg pain is sciatica. Aching in the buttock and back of the thigh is very common, and it often comes from joints and muscles in the back rather than a nerve. That kind usually stops above the knee, feels like a deep ache, and has no pins and needles with it.

True nerve root pain usually goes below the knee, often into the foot, and usually brings pins and needles, numbness or weakness. That distinction changes the plan, so tell me exactly where yours goes.

5. Why nerve pain feels so different

Nerve pain does not feel like ordinary pain, and that is one reason it frightens people.

It burns. It shoots. It feels electric, or like a hot wire, or like cold water running down the leg. Parts of your leg or foot go numb or tingle. Sometimes your back barely hurts at all and the leg is unbearable.

The single most important thing to understand: nerve pain is not the same as nerve damage. An irritated nerve is a noisy nerve. It fires when it should not. It sends signals your brain reads as burning, or tingling, or numbness. That is a nerve complaining, not a nerve dying.

Numbness and pins and needles work the same way. They are the nerve misfiring, not the nerve failing. They usually fade as the irritation settles, though they often take longer than the pain does.

The exception, and the reason for section 16, is weakness that is getting worse. Pain and numbness can be waited out. Weakness that is progressing should be looked at.

6. What scans show

Researchers scanned lots of people who had no back pain at all. Then they counted what showed up.

In people with no pain:

• At age 20, about 3 in 10 already had a disc bulge. By 80, more than 8 in 10 did.
• About 3 in 10 people in their twenties had a disc protrusion, and that barely rose with age.
• At 60, about 9 in 10 had disc degeneration.

These findings are the inside version of grey hair. Finding one does not, by itself, mean it is causing your pain.

A scan can be genuinely useful with sciatica, more so than with ordinary back pain, because if surgery is being considered we need to know which nerve root is involved and why. But a scan early on, when the plan is going to be the same either way, mostly just gives you frightening words to worry about.

Words like herniation, prolapse, extrusion and nerve root compression sound severe. Section 7 is the reason they are much less severe than they sound.

7. The best news in this guide: discs shrink

This is the section worth reading twice.

Researchers gathered the studies that scanned people with disc herniations, then scanned them again later to see what had happened. The discs shrink on their own.

Better than that, the pattern is the opposite of what anyone expects. The worse the herniation looks, the more likely it is to shrink. Here is what they found:

• A sequestration, where a fragment has broken off completely and the worst kind on paper: 96 in 100 shrank. In 43 in 100 it disappeared entirely.
• An extrusion, where material has squeezed out through the outer ring: 70 in 100 shrank.
• A protrusion, a smaller bulge: 41 in 100 shrank.
• A simple bulge: 13 in 100 shrank.

Read that again. The most alarming word on your scan report is attached to the best odds.

The reason makes sense once you hear it. When disc material escapes and comes into contact with your blood supply, your body treats it as something that does not belong there. Your immune system moves in and clears it away. The more material that escapes, and the further it gets, the more your body has to work with.

A tight little bulge that never breaks through stays where it is. A dramatic escaped fragment gets mopped up.

So if you have been handed a report with the word extrusion or sequestration on it, that is not the disaster it sounds like. On the evidence, it is the version most likely to resolve on its own.

8. What recovery usually looks like

Most people with sciatica get substantially better over weeks to a few months, without surgery.

A few things worth knowing so they do not worry you:

• Recovery is rarely a straight line. Good days and bad days, in no obvious order, is normal.
• The pain usually settles before the numbness does. Numbness and tingling can hang about for months after the pain has gone. That is expected and it is not a bad sign.
• Leg pain often eases before back pain. Many people find the leg quietens down and they are left with a sore back, which feels like a step backwards. It is the opposite. See section 12.
• The first few weeks are usually the worst. If you are in that stretch now, you are in the hardest part.

What I need to know at each appointment is not just your pain score. It is where the pain is now compared with last time, and whether anything has changed about your strength, numbness or bladder.

9. Surgery, and when it helps

Some people ask about surgery straight away. Others are terrified of it. Here is the honest picture.

For sciatica from a disc, surgery works. It relieves leg pain, and it does so faster than waiting.

But the trials that followed people for a year or two found something important. By then, the people who had surgery and the people who waited had ended up in much the same place.

So for most people, surgery is a decision about how fast you get there and how much you can bear in the meantime. It is usually not a decision about where you end up.

That means:

• There is no rush for most people, and waiting does not spoil your chances.
• If your pain is severe, not settling, and wrecking your life after a few months of proper treatment, surgery is a reasonable choice and worth discussing with your GP.
• The exceptions are urgent. Cauda equina syndrome and weakness that is getting worse are not wait and see situations. See section 16.

10. A word about painkillers

This section surprises people, so it is worth being clear.

Many people with sciatica are given gabapentin or pregabalin. National guidance advises against this.

NICE guidance on sciatica says: do not offer gabapentinoids, other epilepsy drugs, steroid tablets or diazepam type drugs for managing sciatica, because there is no overall evidence of benefit and there is evidence of harm. It also says opioids should not be offered for long lasting sciatica.

Please do not stop any medication on the strength of this guide. Some of these drugs need reducing gradually, and stopping suddenly can be unpleasant. Take this to your GP and ask about it.

Anti-inflammatory tablets have limited evidence in sciatica and real risks, especially over 60. Anti-inflammatory gels carry much less risk than tablets. If you are taking painkillers regularly rather than now and then, a free medicines review with your pharmacist is a genuinely useful half hour.

11. What turns your pain up and down

• Sleep. Poor sleep is one of the strongest signs of a bad pain day ahead, and sciatica is very good at wrecking sleep.
• Stress and worry. Especially worry about nerve damage, which is why sections 5 and 7 matter.
• Mood. Low mood and pain feed each other, both ways.
• What you believe. Believing a nerve is being crushed and destroyed is linked to worse outcomes, and it is usually not what is happening.
• Sitting. Often the single worst thing for disc related sciatica. See section 13.
• Activity. Too much too soon turns it up. So does too little for too long.
• General health. Smoking is linked to slower disc recovery.

12. Moving is safe, and finding what eases it

Bed rest used to be the standard advice for sciatica. It was dropped because trials showed it made people worse. Staying as active as you can manage beats resting, even while it hurts.

That does not mean pushing into severe pain. It means keeping moving within what you can tolerate, and expecting some discomfort rather than none.

The one idea worth learning: which direction eases your leg.

Most people with disc related sciatica find that one direction of movement helps and another makes it worse. Often, though not always, gently arching backwards eases the leg and bending forwards aggravates it. For some people it is the other way round, and for some it is leaning to one side.

What you are watching for is not whether the pain gets smaller. It is where the pain goes.

Pain that moves out of your leg and back towards your spine is a good sign, even if your back hurts a bit more in the process. Pain that travels further down your leg is a sign to stop doing that one. This is called centralisation, and it is one of the more useful things you can learn to read in your own body.

We will work out your direction together. Once you know it, you have something you can do several times a day, and something to avoid.

• Alongside that:
• Walking is usually good, in short frequent bouts rather than one long one.
• Do not hunt for the perfect exercise. Consistency beats perfection.
• Some soreness while you build back up is expected. Pain that rises while you move and settles back to normal within about a day is fine. Pain still up the next day means you did a bit too much, not that you did harm.

13. Sitting, driving and sleeping

These three catch nearly everyone with sciatica, so they are worth their own section.

Sitting is often the worst position for disc related sciatica. Sitting raises the pressure inside your discs more than standing does, and slouched sitting more than upright.

• Break sitting up. Twenty to thirty minutes, then stand and move, even briefly.
• Sit further back in the chair. A rolled towel or small cushion in the small of your back often helps.
• Standing or perching to work for part of the day is worth trying.

Driving is frequently the very worst thing, because it combines sitting, vibration and not being able to shift position.

• Break long journeys every half hour or so. Get out and walk about.
• Raise the seat a little and reduce how far back it reclines.
• A rolled towel in the small of your back helps many people.
• If you drive for work and it is really aggravating things, that is worth raising with your employer early rather than late.

Sleeping. There is no single correct position, only what works for you. Two that help most people:

• On your side, knees bent, with a pillow between your knees so your top leg does not drop across.
• On your back, with a pillow or two under your knees.

If you get a stretch of good sleep, that is worth as much as any treatment.

14. Pacing and flare-ups

A good day comes. You seize it and get everything done. Then you pay for it for three days. Over months the trend quietly goes down.

• Pacing is the way out:
• Work out what you could manage on almost any day, including a bad one.
• Do that amount every day, good and bad. Not as much as you can manage.
• Once it feels easy, add about a tenth more each week.
• Break big jobs into chunks. Take breaks before you need them, not after.

Flare-ups are normal, and they do not mean the disc has gone again. They are usually a pile-up: a hard week, two bad nights, a long drive, a stressful event.

Keep moving gently, drop back to your baseline for a few days, go back to the direction that eases your leg, and use whatever settles it.

Get in touch if it is not settling as it normally does, or if anything in section 16 applies.

15. What treatment does, and what it does not

Hands-on treatment works through everything above. It closes the gate. It calms the sensitivity. It relaxes muscles that have tightened to protect you. It gives you a spell where moving feels easier and safer. That is a real effect and it is worth having.

What it does not do is push a disc back in. Nothing gets put back. Nothing is out of place. Anyone who tells you they can pop a disc back in is describing something that does not happen.

What treatment can do is help you move more comfortably, help you find and use your direction, keep you as active as possible while your body does the work described in section 7, and keep an eye on the things in section 16 as we go.

That last part matters with sciatica more than with ordinary back pain. Part of what you are paying me for is to keep checking, at every appointment, that this is still behaving the way it should.

One note on progress. Pain scores bounce around and can be disheartening. Better questions are: is the pain covering less of my leg than it was? Can I sit for longer? Am I sleeping better? Can I walk further? Those improve before the pain score does.

16. When to get urgent help

Almost all sciatica, including severe sciatica, is not an emergency. A few things are, and with sciatica this genuinely matters, so please read this section properly.

Go straight to A&E, or call 999

Do not wait to see if these settle. Do not wait to contact me or your GP first. If you are offered a routine appointment, say you are worried about cauda equina syndrome and ask to be seen today.

• Numbness or a changed feeling between your legs, around your back passage or genitals. Including toilet paper feeling different when you wipe, or a shower feeling different there.
• Trouble starting to wee. Not being able to feel it coming out. Losing the feeling of a full bladder. Any new loss of control of your bladder or bowels.
• New numbness during sex, or new trouble getting an erection.
• Sciatica in both legs at once, or sciatica that has spread from one leg to the other.
• New or quickly worsening weakness in one or both legs, or your legs giving way.

Those are the warning signs that the bundle of nerves at the bottom of your spine is being squashed. It is called cauda equina syndrome. It is rare. It is also time critical, and the national plan expects a scan within hours. It is far better to go and be told you are fine than to wait and wonder.

Contact your GP or NHS 111 today

• Weakness that is getting worse. Especially if your foot is starting to drag or catch when you walk, or you cannot lift the front of your foot properly. This is called foot drop, and it should be assessed rather than waited out.
• Numbness that is spreading over days rather than staying put.
• Back or leg pain with a fever, shivering, or feeling generally unwell.
• Back pain with weight loss you cannot explain, night sweats, or a past history of cancer.
• Severe back pain straight after a bad fall or accident.

Everything else, including a very painful few days, can wait for a normal appointment.

17. If you want to read or watch more

Start here

• Tame the Beast. A five minute animation by Professor Lorimer Moseley. The best possible starting point. tamethebeast.org
• Flippin' Pain. A UK campaign about long lasting pain. flippinpain.co.uk
• Retrain Pain. Free, very short illustrated lessons. retrainpain.org
• NHS advice on sciatica. nhs.uk/conditions/sciatica
• NHS exercises for sciatica. nhs.uk/live-well/exercise/exercises-sciatica-problems Practical help
• The Pain Toolkit, by Pete Moore, who lives with long lasting pain himself. Very good on pacing and boom and bust. paintoolkit.org
• Recovery Strategies, by Greg Lehman. A free illustrated workbook, one idea per page. greglehman.ca/recovery-strategies-pain-guidebook

Books

• Explain Pain, by David Butler and Lorimer Moseley. The standard patient friendly version of the science in this guide.
• The Explain Pain Handbook: Protectometer, by the same authors.
• Painful Yarns, by Lorimer Moseley. The same ideas as short, funny stories.

The research behind this guide

• Melzack R, Wall PD. Pain mechanisms: a new theory. Science, 1965. The original pain gate paper.
• Chiu CC et al. The probability of spontaneous regression of lumbar herniated disc: a systematic review. Clinical Rehabilitation, 2015. The source of the shrinkage figures in section 7.
• Brinjikji W et al. Imaging features of spinal degeneration in asymptomatic populations. American Journal of Neuroradiology, 2015. The scan figures in section 6.
• Peul WC et al. Prolonged conservative care versus early surgery in patients with sciatica caused by lumbar disc herniation: two year results. BMJ, 2008. The surgery comparison in section 9.
• Lurie JD et al. Surgical versus non-operative treatment for lumbar disc herniation: eight year results of the SPORT trial. Spine, 2014.
• NICE guideline NG59: Low back pain and sciatica in over 16s. The medication advice in section 10 comes from recommendations 1.2.16 and 1.2.17.
• Hartvigsen J et al. What low back pain is and why we need to pay attention. The Lancet, 2018.

Bring any of this to your next appointment. Especially the parts that did not sit right, or that felt uncomfortably familiar. Those are usually the most useful things to talk through.

This guide is general information. It does not replace the advice I give you in clinic.