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.

What does the lumbar spine do?

Your lumbar spine has important functions, including the following:

• Supporting your upper body and distributing your body weight: It supports your head and the 2 upper sections of your spine (cervical and thoracic). It connects to your pelvis, transferring body weight from your upper body to your legs. It allows you to lift and carry.
• Allowing you to move your body: The muscles in your lumbar spine allow you to move your lower back in all directions; front to back, side to side, and twist. The cauda equina nerves control leg movement and feeling.
• Protecting your spinal cord and cauda equina: Your vertebrae wrap around your spinal cord and protect it.

What health conditions affect the lumbar spine?

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

• lumbar spondylolisthesis and lumbar stenosis
• herniated disc and degenerative disc disease
• vertebral compression fracture
• cauda equina syndrome
• lumbar lordosis — when your lower back becomes too curved, putting pressure on your vertebrae

Other conditions affecting your lumbar spine include:

• tumours and cysts
• congenital problems (problems present from birth)
• osteoarthritis
• injury or trauma
• infections
• muscle spasms

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:

• lower back pain
• sciatica
• reduced movement in your back or hips
• weakness, numbness, tingling in your back, hips, thighs or legs

How do I prevent back injuries?

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

• Being physically active: Regular exercise improves flexibility, muscle strength and bone health. Start slowly and gradually increase intensity. A physiotherapist or exercise physiologist can create a program for you.
• Maintaining a healthy body weight: If you are living with overweight or obesity, your spine carries an extra load.
• Quitting smoking: Smoking increases your risk of arthritis, osteoporosis and back pain.
• Safe manual handling: If you have a physical job, you are at risk of back injury. Your employer must keep your workplace safe and teach you how to handle heavy loads safely.
• Ensuring healthy workplace design and posture: Your work may require you to sit or stand for many hours. Poor posture can cause back injury or pain. Your workstation should be designed to allow you to stand and sit in a way that supports your back.
• Managing your stress: When you’re stressed, the muscles in your body may tense up which can make back pain worse. Learning some relaxation techniques can help.

How are lumbar spine issues treated?

Treatments for lumbar spine issues include:

• exercise and physiotherapy
• ice or heat
• cognitive behaviour therapy
• medicines — pain relievers, muscle relaxants, anti-inflammatories or steroid injections
• surgery — lumbar spine decompression (laminectomy), lumbar disc replacement surgery, or lumbar fusion (which permanently joins together one or more vertebrae)

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.

When should I see my doctor?

You should see your doctor if:

• your pain is getting worse over a few weeks
• you are in distress
• your ability to move is limited

When is back pain an emergency?

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

• changes in your bladder and bowel movements, especially if you cannot pass urine
• changes in feeling around your bottom and inner thighs
• sudden significant weakness or numbness, or pins and needles in your legs
• a fever

Resources and support

• Visit WorkSafe Victoria to watch videos explaining manual handling in the workplace and how to prevent injury.
• Find a physiotherapist — use the Australian Physiotherapy Association search tool to find physiotherapists to prevent or treat lumbar spine injury.
• See the Musculoskeletal Australia website for information about back pain and tips to manage and prevent back pain.
• Learn about why it is important to be physically active at the Australian Physiotherapy Association website.