What Is Sciatica? Causes, Symptoms, and When to See a Physio

4 min read • Physiophi, Jindalee Brisbane

Sciatica can bring your day to a halt. That sharp, electric pain shooting from your lower back through your hip and down your leg is hard to ignore. This guide covers what sciatica actually is, what triggers it, and what to do next.

What is sciatica?

Sciatica is an umbrella term used to describe nerve pain that travels down the leg. It is not a diagnosis in itself — it is a symptom, and one that can arise from several different underlying causes. Research suggests that up to 40% of people will experience sciatica at some point in their lives. The pain typically originates in the lower back or buttock and radiates down one leg, sometimes as far as the foot. Pinpointing what is driving that nerve irritation is what guides effective treatment.

What causes sciatic nerve pain?

Nerve pain down the leg can stem from a number of structural and soft tissue causes. The most well-supported in the clinical literature include:

• Disc pathology: Disc bulges, herniations, and degenerative disc changes are among the most common drivers of sciatica. When disc material encroaches on a nearby nerve root, it can trigger the characteristic radiating pain pattern.
• Lumbar spinal stenosis: A narrowing of the spinal canal that reduces space around the nerve roots, more commonly seen in older adults and often producing symptoms with walking or standing.
• Spondylolisthesis: A condition where one vertebra slips forward over another, which can compress nerve roots and produce leg pain.
• Piriformis syndrome: The piriformis muscle in the deep buttock can irritate or compress the sciatic nerve, particularly relevant when leg pain arises without clear spinal pathology.
• Pregnancy: Postural changes, increased load through the pelvis, and hormonal effects on ligament laxity can all contribute to nerve-related leg pain during pregnancy.

Because the cause shapes the treatment, an accurate assessment matters. The same symptom can have very different origins and different solutions.

What does sciatica feel like?

The clinical presentation of sciatica is fairly consistent, which helps distinguish it from other types of back or leg pain. Symptoms almost always affect one side of the body and follow a predictable path down the leg:

• Shooting or burning pain down one leg
• Numbness or tingling in the leg or foot
• Muscle weakness in the affected leg
• Pain that worsens when sitting

How to relieve sciatica pain

Evidence consistently supports staying active over bed rest for sciatica. A 2012 Cochrane review found that exercise therapy and advice to remain active are more effective than rest alone. For mild to moderate symptoms, these approaches can help in the short term:

• Nerve mobilisation: Gentle nerve gliding exercises can help reduce tension along the sciatic nerve and improve mobility. A physiotherapist can show you which movements are appropriate for your presentation.
• Piriformis stretch: Useful when piriformis irritation is contributing. Lie on your back, cross one ankle over the opposite knee, and gently pull the thigh toward you. Hold for 30 seconds.
• Heat and ice: Ice can help in the early inflammatory phase; heat is more appropriate for ongoing muscular tension. Neither addresses the underlying cause but can support comfort.
• Stay active: Short walks and gentle movement are consistently supported over rest. Prolonged sitting tends to increase nerve sensitivity and should be avoided where possible.

These strategies can provide relief but do not address the underlying cause. If symptoms persist beyond a few weeks, a thorough physiotherapy assessment is the most effective next step.

When should you see a physio for sciatica?

Most sciatica episodes improve within 6 to 12 weeks with appropriate management, but that does not mean waiting it out without guidance. Evidence supports early physiotherapy intervention for better outcomes. Seek a professional assessment if:

• Symptoms have not improved after 2 to 3 weeks of conservative self-management
• Pain is disrupting sleep, work, or daily function
• You are experiencing progressive leg weakness or significant numbness
• Symptoms are worsening rather than stabilising
• You have had multiple episodes and want to understand and address the underlying cause

A physiotherapy assessment will identify the likely source of your symptoms, rule out anything requiring medical referral, and establish a structured rehabilitation plan. The goal is not just pain relief but restoring function and reducing the risk of recurrence.