beginning of content

Lumbar spine

7-minute read

Key facts

  • Your lumbar spine (lower back) includes 5 bones (vertebrae L1 to L5), discs, muscles, ligaments and blood vessels.
  • Your lumbar spine supports your upper body, distributes your body weight, allows you to move and protects your spinal cord.
  • Conditions affecting your lumbar spine include osteoporosis, trauma, cancer and infections.
  • You can help prevent back injury by keeping active, being a healthy weight and handling heavy loads safely.
  • Treatments for back injury depend on the cause, and may include exercise, physiotherapy, cognitive behaviour therapy, medicines or surgery.

What is the lumbar spine?

Your lumbar spine (lower back) includes 5 bones (vertebrae L1 to L5), discs, muscles, ligaments and blood vessels. It is a part of your spine, found below your thoracic spine (middle part of your spine) and above your sacrum (lowest part of your spine, connected to your pelvis). It curves slightly inwardly. The lumbar vertebrae (lower back bones) are larger than your other vertebrae.

Your spine protects your spinal cord by wrapping around it. Your spinal cord ends at the top of your lumbar spine. Nerve roots called ‘cauda equina’ at the end of your spinal cord travel through your lumbar spine to your sacrum.

3 groups of muscles attach to your lumbar spine:

  1. Extensor muscles — these hold up your spine and allow you to bend backwards.
  2. Flexor muscles — these allow you to bend forwards, and lift and arch your lower back.
  3. Oblique muscles — these help you rotate your spine and have good posture.

Overall, your lumbar spine lets you walk, run, sit, lift and move your body in many directions.

Diagram of the different regions of the spine.

What does the lumbar spine do?

Your lumbar spine has important functions, including the following:

What health conditions affect the lumbar spine?

Many health conditions can develop in your lumbar spine, including:

Other conditions affecting your lumbar spine include:

Lower back pain can also be caused by some lifestyle factors.

Conditions that can affect the lumbar spine

The conditions that affect your lower back can cause chronic (long-term) symptoms of:

How do I prevent back injuries?

You can reduce your chances of having back injuries by taking these steps:

How are lumbar spine issues treated?

Treatments for lumbar spine issues include:

Your doctor may recommend surgery if your condition is urgent, other treatments failed or your symptoms are getting worse, if you are healthy enough for surgery. Read about questions to ask before surgery.

ASK YOUR DOCTOR — Preparing for an appointment? Use the Question Builder for general tips on what to ask your GP or specialist.

When should I see my doctor?

You should see your doctor if:

When is back pain an emergency?

You should go to a hospital emergency department if you have back pain and you have:

FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.

Resources and support

Check your symptoms Find a health service

Healthdirect 24hr 7 days a week hotline

24 hour health advice and information you can count on

1800 022 222

Government Accredited with over 140 information partners

We are a government-funded service, providing quality, approved health information