What Is Sciatica Exactly?

By Dr. Eleanor Smith, DPT
Medically Reviewed by Dr. Alex Roberts, BSc Physiology
Last Updated: January 2026

Sciatica is not a condition on its own.

It’s a symptom caused by irritation or inflammation of the sciatic nerve.

That’s the most important thing to understand.

Sciatica Definition (Explained Simply)

Sciatica means:

"Pain Caused By Irritation Of The Sciatic Nerve"

The sciatic nerve runs from your lower back, through the hips and buttocks, and down each leg.

When it becomes irritated, pain follows its path.

What Is The Sciatic Nerve?

The sciatic nerve is:

• The Largest Nerve In The Body
  
  

• Responsible For Leg Sensation And Movement
  
  

• Highly Sensitive To Inflammation And Pressure
  
  

Even mild irritation can cause severe pain.

What Does Sciatica Feel Like?

Sciatica often feels like:

• Sharp Or Burning Pain
  
  

• Electric Or Shooting Sensations
  
  

• Deep Ache In The Hip Or Leg
  
  

• Numbness Or Tingling In The Foot Or Calf
  
  

This is different from general muscle pain.

Is Sciatica Serious?

Sciatica is rarely dangerous, but it can become serious if left untreated.

Ongoing inflammation can:

• Keep The Nerve Hypersensitive
  
  

• Cause Recurring Pain
  
  

• Affect Movement And Sleep
  
  

Early understanding matters

Sciatica Vs General Nerve Pain

The difference between sciatica and other nerve pain is the clear leg pathway.

Sciatica:

• Travels Down One Leg
  
  

• Is Linked To The Lower Spine
  
  

• Flares With Sitting Or Pressure
  
  

This pattern makes it recognisable.

Why Understanding Sciatica Matters

When people misunderstand sciatica, they:

• Chase Temporary Fixes
  
  

• Get Conflicting Advice
  
  

• Delay Real Relief
  
  

Understanding what sciatica actually is makes the next steps obvious.

If you feel like you may have sciatica, find out the best fixes for sciatica in 2026 that actually works. Click Below.

Best Fixes For Sciatica