You woke up this morning in pain. The pain starts in your lower back, travels down into your buttock, and radiates into your thigh—sometimes all the way to your calf or foot. You recognize this feeling. Maybe it’s been going on for a few days. Maybe for months.

This is sciatica. And if you are reading these lines, you want a concrete answer: what exactly is it, why does it hurt so much, and above all, how do you get over it.

This guide compiles what physical therapists, doctors, and—most importantly—thousands of patients have learned about sciatica. No useless jargon. Clear answers, in order.

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1. What exactly is sciatica?

Sciatica is not a disease in the strict sense. It is a symptom: pain caused by the compression or irritation of the sciatic nerve.

The sciatic nerve is the longest and thickest nerve in the human body. It originates in the lower lumbar region (from nerve roots L4, L5, S1, S2, S3), crosses the pelvis, passes under—or sometimes through—the piriformis muscle in the buttock, and then descends along the entire leg to the foot.

When something compresses this nerve anywhere along its path, you feel pain that follows this route. This is why sciatica can manifest in the lower back, buttock, thigh, and leg simultaneously—or only in a portion of this path, depending on the location of the compression.

L4, L5, or S1 sciatica: What's the difference?

• L4 root: pain on the side of the thigh and knee, sometimes numbness on the inside of the calf
• L5 root: pain on the outer side of the leg, the top of the foot, and the big toe—this is the most frequent
• S1 root: pain behind the thigh, the calf, the heel, and the sole of the foot up to the little toes

This distinction is useful for your doctor during diagnosis—and for you, when describing exactly what you feel.

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2. Main causes of sciatica

Herniated disc: responsible in 90% of cases

Intervertebral discs are gelatinous cushions located between each vertebra. When the outer wall of a disc tears, the gelatinous core can bulge outward. This protrusion then presses directly onto a sciatic nerve root.

The majority of hernias responsible for sciatica occur at the L4-L5 and L5-S1 levels, at the very bottom of the back—where the mechanical stress on the spine is highest.

The good news: in 90% of cases, a herniated disc regresses naturally without surgery. The body gradually reabsorbs the protruding disc material. This takes between 4 and 12 weeks for acute sciatica, sometimes longer.

Piriformis syndrome: the forgotten "false sciatica"

The piriformis is a small, deep muscle located in the buttock that connects the sacrum to the hip. In 85% of the population, the sciatic nerve passes just underneath it. When this muscle contracts or becomes inflamed—following prolonged sitting, sports, or trauma—it can compress the sciatic nerve and cause pain identical to true sciatica.

This is called piriformis syndrome, sometimes referred to as "false sciatica" or "pseudo-sciatica." It accounts for about 6% of sciatica-type pain cases in France—but it is often misdiagnosed because imaging (MRI, CT scans) often appears normal.

👉 Do you have deep pain in your buttock with no real disc issue visible on an MRI? Read our dedicated article:

Piriformis syndrome: false sciatica explained simply.

Pregnancy

In pregnant women, sciatica is very common starting from the 5th month. The causes are multiple: weight gain, shift in the center of gravity, hormonal ligament relaxation (relaxin), and direct pressure from the uterus on the sciatic nerve. It affects about 1 in 4 pregnant women in the 3rd trimester.

The good news: it generally disappears after childbirth. In the meantime, natural solutions and targeted support are the only options, as anti-inflammatory drugs are contraindicated during pregnancy.

Sedentary lifestyle and prolonged sitting

Sitting for 6 to 8 hours a day increases the pressure on intervertebral discs by 40% compared to standing. Over months or years, this can cause a herniated disc or worsen existing disc disease.

Spinal stenosis

In people over 60, sciatica is often linked to a narrowing of the spinal canal. Pain is often bilateral and worsened by walking—it subsides when sitting or leaning slightly forward.

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3. Symptoms: how to recognize true sciatica

True sciatica is distinguished by several typical characteristics:

Signs that lead to a diagnosis:

• Pain that starts in the lower back or buttock and travels down the leg in a specific direction
• Unilateral pain in the vast majority of cases (only one leg affected)
• Aggravation when coughing, sneezing, or exerting effort
• Aggravation when sitting, partial relief when lying down
• Tingling, pins and needles, numbness, or a burning sensation along the path
• Sometimes: muscle weakness in the leg or foot

Warning signs that require urgent consultation:

• Loss of sphincter control (urinary or fecal incontinence) → neurosurgical emergency
• Progressive paralysis of a leg
• Pain after severe trauma (fall, accident)
• Fever associated with lower back pain
• Sudden onset of bilateral sciatica

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4. The 5 mistakes that worsen sciatica

Mistake 1: Prolonged total rest Total inactivity makes sciatica worse. Strict rest is only recommended for the first 24-48 hours of an intense acute crisis. Beyond that, gentle mobility aids nerve recovery.

Mistake 2: Leaning forward to "stretch" In the acute phase, flexing the trunk increases intradiscal pressure. Forward flexion should be avoided during the first few weeks.

Mistake 3: Taking anti-inflammatories without treating the cause NSAIDs provide temporary relief but do not treat the nerve compression. They can mask the pain and lead you to perform activities that worsen the problem.

Mistake 4: Waiting for it to pass without doing anything If the pain has been debilitating for more than 4 weeks, passive waiting is not a strategy. Physical therapy, support, and adapted exercises significantly accelerate healing.

Mistake 5: Sleeping in a bad position Sleeping on your stomach creates excessive lordosis and worsens lumbar compression. The best position: on the side opposite to the pain, with a pillow between your knees.

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5. Natural solutions to relieve sciatica

Heat and cold: when and how to use them

The rule is simple but often poorly applied:

• Acute phase (0 to 72 hours): cold reduces inflammation. 15 to 20 minutes, 3 to 4 times a day, never directly on the skin.
• Sub-acute and chronic phase (after 72 hours): heat relaxes muscles and relieves pain. Gentle, prolonged heat is much more effective than intense, brief heat.

Physical therapy

Physical therapy is the reference treatment. It relies on: gentle joint mobilizations, myofascial release, sciatic nerve neuromobilization, and an exercise program adapted to your situation.

Osteopathy

Particularly effective for piriformis syndrome and pain of mechanical origin (posture, muscle imbalance).

Corticosteroid injections

In case of severe sciatica resistant to conservative treatments. Temporary effect but can help overcome a difficult hurdle.

Therapeutic red light (photobiomodulation)

Less known to the general public, therapeutic red light acts at a cellular level: it stimulates the mitochondria of nerve and muscle cells, reducing local inflammation and accelerating tissue regeneration. Unlike heat, it can be used during the acute phase—it does not increase vasodilation and carries no risk of worsening active inflammation.

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6. The 5 exercises recommended by physical therapists

Exercise 1 — Piriformis stretch

Lie on your back. Bend the painful leg and cross it over the opposite leg (ankle on knee). Grab the back of the opposite thigh and pull gently toward your chest. You should feel a deep stretch in the buttock. Hold for 30 seconds, repeat 3 times, twice a day.

Exercise 2 — Knee-to-chest

Lying on your back, bring one knee toward your chest; the other leg remains straight on the floor. Hold for 30 seconds. Switch legs. 3 repetitions on each side.

Exercise 3 — Lumbar extension (sphinx pose)

Lie on your stomach, place your elbows under your shoulders, and gently lift your upper body. Keep your hips on the floor. Hold for 30 to 45 seconds. Repeat 3 times. Stop if the pain in the leg intensifies.

Exercise 4 — Cat-cow mobilization

On all fours, hands under shoulders. Inhale while gently arching your back (cow). Exhale while rounding your back as much as possible (cat). Slow, fluid movements. 10 repetitions, 2 sets.

Exercise 5 — Gentle abdominal bracing

Supported on your forearms and knees, keep your back straight. Gently contract your abdominals. 20 to 30 seconds, 3 repetitions. This exercise is more for preventing relapses than for the acute crisis.

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7. Heat, red light, and support: why the combination changes everything

• Support reduces movements that worsen compression without completely immobilizing
• Diffuse heat relaxes deep muscles (piriformis, quadratus lumborum, glutes)
• Gentle compression stimulates skin mechanoreceptors, which reduces pain perception (gate control principle in neurophysiology)
  
• Red light penetrates deeper than heat — it reaches the piriformis and nerve roots. The 105 medical LEDs at 660 nm penetrate where heat alone cannot—wavelength identical to that used in professional sports medicine and validated in physical therapy

8. When to consult a doctor: warning signs

Consult your doctor within the week if:

• The pain has been debilitating for more than 3-4 days despite treatments
• You have persistent pins and needles or numbness
• You start to experience weakness in your leg

Consult immediately if:

• You lose control of urine or stool
• The pain spreads to both legs simultaneously
• You have a fever associated with lower back pain
• Numbness or paralysis sets in rapidly

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9. How to prevent recurrences

Sciatica recurs in 30 to 40% of cases within 5 years following a first episode.

The 7 anti-recurrence habits:

1. Move regularly — Daily walking (30 minutes) is the best preventative medicine.
2. Strengthen deep abdominals — Regular bracing (3x/week) reduces the risk of relapse by 50%.
3. Correct sitting posture — Back supported, breaks every hour to stand for 2 minutes.
4. Learn to bend correctly — Bend your knees, not your back, to pick up an object.
5. Maintain a healthy weight — Each kilo around the belly increases disc pressure by ~4 kilos.
6. Manage stress — Chronic stress causes muscle tension that maintains nerve compression.
7. Equip yourself with a support solution for bad days — Intervene at the first signs before the crisis sets in.

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10. FAQ — Most frequently asked questions about sciatica

Can sciatica go away on its own? Yes, in the majority of cases. 80% of acute sciatica improves in 4 to 6 weeks with conservative treatment.

How long does a sciatica crisis last? An acute crisis generally lasts between 4 and 6 weeks. Sciatica that persists beyond 3 months is considered chronic.

Can you work with sciatica? It depends on the intensity of the pain and the type of work. Sedentary work can be maintained with ergonomic adaptations and lumbar support.

Is a lumbar belt reimbursed by Social Security? Some belts are partially reimbursed by prescription (according to the LPPR). Therapeutic braces sold without a prescription are generally not covered, but some mutual insurance companies cover a portion of the cost upon presentation of an invoice.

Can you play sports with sciatica? Yes, but not just any sport. Swimming, cycling in an upright position, and walking are recommended. Running and sports involving trunk rotation should be avoided during the acute phase.

Can sciatica cause paralysis? In rare cases, if the compression is severe and prolonged. Sciatica with progressive leg weakness must be treated quickly.

Sciatica and pregnancy: is it dangerous for the baby? No. Pregnancy-related sciatica is not dangerous for the baby. Natural solutions (exercises, suitable belt, gentle heat) can relieve it without risk.

Which doctor should I consult for sciatica? In the first instance, your general practitioner. If the pain persists, they will refer you to a rheumatologist or a neurosurgeon. An osteopath or physiotherapist can be consulted in parallel without a prescription.

Does heat worsen sciatica? In the very acute phase (first 48-72 hours), it can aggravate active inflammation. After this period, it is beneficial for relaxing the muscles.

Can you prevent a first bout of sciatica? Yes. Regular physical activity, abdominal strengthening, ergonomics at work, and good posture significantly reduce the risk. Smoking is a little-known aggravating factor.

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In summary

Sciatica is a common, often disabling nerve pain, but in the vast majority of cases, it can be treated without surgery. The keys to recovery: understanding the cause, adopting the right actions from the start, not remaining immobile, and using the right support solutions between physiotherapy sessions.

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This content is provided for informational purposes and does not replace medical advice. In case of severe, persistent pain or if accompanied by neurological signs, consult a doctor or physiotherapist.