Why Does My Lower Back Hurt?

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

Lower back pain is one of the most common reasons people search for answers online.

It can start suddenly, worsen in the morning, or flare up when you sit, bend, or lie down.

In many cases, lower back pain isn’t random. It usually has a clear mechanical or nerve-related cause.

Common Reasons Lower Back Pain Happens

Lower back pain often comes from one of these:

• Muscle strain from lifting, bending, or poor posture
  
  

• Joint stiffness from long periods of sitting
  
  

• Disc pressure in the lower spine
  
  

• Nerve irritation affecting the lower back and leg
  
  

This explains why people experience pain when bending, sitting, or first getting out of bed.

When Lower Back Pain Feels Worse

You may notice lower back pain:

• Worse in the morning due to overnight stiffness
  
  

• Worse when sitting for long periods
  
  

• Worse when lying down or changing positions
  
  

• Sudden and sharp after a small movement
  
  

These patterns help narrow down whether the issue is muscular or nerve-related.

Lower Back Pain On One Side Or Spreading To The Leg

If your lower back pain is:

• Only on the left side or right side
  
  

• Spreading into the buttock or leg
  
  

• Accompanied by tingling, burning, or weakness
  
  

This can indicate nerve involvement rather than simple muscle pain.

Many people describe this as lower back pain that “travels” or feels deep and electric.

Can Lower Back Pain Be Nerve Pain?

Yes. Lower back pain can be nerve-related, especially when:

• Pain spreads down one leg
  
  

• Pain changes with posture or movement
  
  

• There is numbness or tingling
  
  

• Rest doesn’t fully settle it
  
  

This is where sciatica often enters the picture.

Find out the difference between nerve pain vs muscle pain here.

Is Lower Back Pain Sciatica?

Not all lower back pain is sciatica.

But sciatica often starts in the lower back before moving into the hip, buttock, or leg.

Knowing the difference early can save months of confusion

Not sure if you have sciatica? Find complete symptoms of sciatica here and confirm. Click Below.

Symptoms Of Sciatica