Sciatica Explained : Symptoms, Diagnosis and Treatments
Sciatica is that intense radiating pain that can shoot from your lower back or buttock down one leg — sometimes all the way to your calf or foot. It’s one of the most common yet misunderstood problems I see in clinic, and it often causes a lot of distress and confusion.
In this article, I’ll explain what sciatica really is, why it happens, and what you can do about it based on the best current evidence. I’ll also cover some important warning signs that should never be ignored and help you tell sciatica apart from other conditions that can cause similar symptoms.
The Information can also be seen in video format below.
What is Sciatica ?
Most people use the word sciatica to describe pain that runs from the lower back or buttock down the leg. But technically, that’s not quite accurate.
The sciatic nerve itself runs from the buttock down the back of the leg — but it’s rarely the structure actually being irritated. In most cases, the problem starts higher up in the lower spine, where individual nerve roots branch out from the spinal cord before joining to form the individual leg nerves, including the sciatic nerve.
When one of these lumbar nerve roots becomes compressed or inflamed — often by a disc bulge or joint swelling — it can send pain, tingling, or numbness down the leg along the same pathway that nerve normally serves.
Common Nerves and Pain Patterns
- L5 and S1 nerve roots → Pain down the back of the leg into the foot (the classic “sciatica” pattern)
- L4 nerve root → Pain down the front of the leg and shin into the big toe
- L3 nerve root → Pain in the front of the thigh and knee
So while the word “sciatica” has stuck, the sciatic nerve itself is not the cause of pain in the typical sciatica pain felt down the back of the leg. It’s the S1 nerve root. Symptoms felt in the front or side of the leg will correspond to other nerve roots depending on which one is being irritated or compressed. And so a more accurate medical term is lumbar radicular pain, or lumbar radiculopathy, if there’s associated numbness or muscle weakness.
Symptoms
- Sharp, burning, or shooting pain down one leg (occasionally both)
- Numbness, tingling, or pins and needles in the leg, foot, or toes
- Muscle weakness in the leg or foot
- Pain that worsens with sitting, bending, coughing, or sneezing (in younger adults)
- Pain that worsens with standing or walking (in older adults)
Why Have I Got It ?
The cause of sciatica often depends on your age and what’s happening in your spine.
In Younger Adults the most common cause is a lumbar disc bulge — sometimes called a “slipped disc”, although that term is misleading. Discs don’t slip; they can bulge, rather like toothpaste being squeezed from a tube.
Small disc bulges are very common and usually harmless, but if a larger bulge presses on a nearby nerve root, it can trigger pain, numbness, or tingling down the leg. Sitting, bending, or coughing can worsen the pain because these increase pressure in the lower spine.
As we age, discs lose some of their sponginess and height — a normal, age-related change.
Older Adults are more likely to develop spinal degeneration, where arthritis, bony spurs, and thickened ligaments narrow the space around the nerves.
This is called spinal stenosis, and it can cause similar leg symptoms — but unlike disc-related sciatica, the pain tends to come on when standing or walking and eases when sitting or bending forward. It can also affect both legs and may limit walking distance.
👉 Read more in my full article on Lumbar Spinal Stenosis.
Is It Definitely Sciatica ?
Not all leg pain coming from the back is caused by nerve root irritation. A very common alternative is lumbar referred pain, which originates from the discs, joints, or muscles of the spine — not the nerves themselves.
Key Differences
- Referred pain tends to spread vaguely from the back into the leg (often not below the knee)
- There’s usually no tingling or numbness
- Back pain is typically worse than leg pain
In contrast, sciatica usually causes leg pain that’s worse than back pain, sometimes with no back pain at all.
Diagnosis is made by a qualified healthcare professional who will assess your movement, reflexes, and nerve function. An MRI scan may be requested if symptoms persist or if serious causes need to be ruled out.
⚠️ Red Flag Warning: Cauda Equina Syndrome
One rare but serious condition linked to back and leg pain is Cauda Equina Syndrome. This occurs when the nerves at the very bottom of the spine become severely compressed and it is a medical emergency.
Seek urgent medical help (ED) if you have back and leg pain plus any of the following:
- Recent loss of bladder or bowel control
- Numbness around the inner thighs, buttocks, or genitals (the “saddle” area)
- Sudden severe weakness or pain in both legs
- In men, a sudden loss of sexual function
If untreated, Cauda Equina Syndrome can cause permanent loss of bladder, bowel, or sexual function — so don’t wait to see if it improves. Get assessed immediately.
👉 You can read more about Cauda Equina Syndrome here.
What Can I do About It ?
The good news: most cases of sciatica improve naturally over time. About 90% of disc-related cases resolve within three to four months as the inflammation and nerve irritation settle.
1. Stay Mobile
Rest may feel tempting, but prolonged bed rest delays recovery. Try to keep gently active within your limits — short walks, light stretches, and changing position often. Avoid long periods of sitting, especially in low or soft chairs.
2. Pain Relief
Over-the-counter painkillers and anti-inflammatories (if safe for you) can help — but take them regularly as directed, not just when the pain flares. If these aren’t enough, speak to your GP or pharmacist. Certain medications designed for nerve pain may be more effective for this type of pain.
3. Managing Night Pain
Many people find side-lying most comfortable, with the painful leg uppermost and a pillow between the knees. If lying on your back, try a pillow under your knees to reduce tension in the lower spine. Pain relief before bed can also help you sleep.
4. Exercise and Physiotherapy
In the early, painful phase, manual therapy, spinal manipulation, traction, or electrotherapy have no evidence of benefitand may even worsen symptoms. You can’t “click” a disc back into place — despite what some may claim.
The only form of therapy supported by evidence at this stage is gentle exercise, within your pain limits.
Early Exercises
- Pendular leg swings in standing (gentle nerve mobility)
- Seated leg swings (nerve glides)
- Pelvic tilts in sitting
- Cat–camel (angry cat–happy cat) movements
- Bridging exercises
Start with small, comfortable ranges and keep pain below about 4/10. If it increases sharply or lingers, scale back. As symptoms ease, gradually build up your strength and activity levels. You can see a video demonstration of these exercises in the video at the top of this page.
👉 When symptoms hopefully start to improve, and pain is now minimal, you can start to introduce more intensive exercises to help ensure a full recovery, and improve your lumbar spine strength and flexibility in order to minimise the chance if developing further episodes of sciatica or other back problems in the future.
See my follow-up video on Exercises for Low Back Pain at this stage.
When to Seek Further Help
If your symptoms haven’t improved after 3-4 months, or if they’re worsening, you may need further investigation.
An MRI scan can show whether a disc is compressing a nerve root. If significant compression is found, a spinal specialist may recommend:
- A nerve root injection (to reduce inflammation and pain)
- A microdiscectomy — a small operation to remove part of the disc pressing on the nerve
Surgery aims to relieve leg pain — it doesn’t usually help back pain alone.
Summary
- Sciatica is pain caused by irritation or compression of one or more nerve roots in the lower back.
- Younger adults: most often due to a disc bulge.
- Older adults: more often due to degenerative changes or spinal stenosis.
- Red flags like bladder or bowel changes, saddle numbness, or severe weakness require urgent medical attention.
- Most cases settle naturally within 3–4 months.
- Staying active, using pain relief wisely, and doing gentle exercises are the most effective self-care measures.
This content is provided for general information only and does not replace professional medical advice. Some articles may contain affiliate links. Full medical disclaimers and affiliate disclosure details are available on the relevant pages of this website.