What causes back pain?

Injury, wear and tear and the normal ageing process are by far the most common causes of back pain.

• Muscle sprains and strains
  In 95 percent of cases of back pain, the cause is linked to the way the bones, ligaments and muscles of your back work together. Although the pain usually comes on suddenly, it is usually due to strain over time rather than the result of you overdoing it just once.

• Nerve problems
  Many people who have back pain often talk about having a "slipped disc". But disc problems actually aren't that common and never happen because the disc has "slipped". It has usually torn and become distorted (prolapsed or herniated) so that is presses against sensitive nerves from the spinal cord. Sometimes a prolapsed disc in your lower back can press on the exiting nerve that forms part of the sciatic nerve, causing pain that runs down one leg. Sometimes a prolapsed disc can also cause numbness or tingling in a small area of your leg or foot. This pain is known as sciatica.

  Triggers for back pain
  These include:
  

  • Poor posture.
  • Lack of exercise.
  • Standing or bending down for long periods.
  • Sitting in a chair that doesn't provide enough back support.
  • Sleeping on a mattress that doesn't provide enough back support.
  • Lifting, carrying, pushing or pulling loads that are simply too heavy, or going about these tasks in the wrong way.
  • A trip or a fall.

  Other conditions

  Most attacks of back pain are not caused by a serious medical condition and last only a few days, subsiding as the body heals. However if your pain prompts you to seek help from your doctor, he or she may want to rule out any one of the following:

  • Osteoarthritis
    This condition is a long-term degeneration of the joints, which makes them less able to withstand stress. It's a wear-and-tear problem that affects most of us as we get older.

  • Inflammatory diseases
    There are many inflammatory diseases (for example, ankylosing spondylitis and rheumatoid arthritis) that cause joints to become inflamed and seize up. These diseases can either directly affect the joints in the back, or cause problems with other joints that lead to pain in the back.

  • Osteoporosis
    This condition causes bones to become fragile and brittle so they fracture easily. The bones of the back and neck are often affected and can become compressed. Fractures due to osteoporosis can lead to changes in posture (for example, developing a stoop or Dowager's hump in your back), muscle weakness, loss of height and deformity of the area affected. Fractures can lead to long-term pain and disability. Osteoporosis is particularly common in women after menopause.

  • Infection and tumors
    Although they are not common causes of back pain, infections can cause pain when they involve the vertebrae, a condition called osteomyelitis, or when they involve the discs that cushion the vertebrae, which is called discitis. Tumors, too, are relatively rare causes of back pain. Occasionally, tumors begin in the back, but more often they appear in the back as a result of cancer that has spread from elsewhere in the body.

  • Spondylolisthesis
    This condition occurs when one vertebra in the spinal column slips over the other. It may be the result of trauma (violent injury), a spinal fracture or arthritis.

  • Spondylolysis
    In this disorder there is a separation or break of the vertebral bone. It can occur as a result of long-term stress on the bones or because of an injury.

  • Emotional stress
    Although the causes of back pain are usually physical, it is important to know that emotional stress can play a role in how severe pain is and how long it lasts. Stress can affect the body in many ways, including causing back muscles to become tense and painful.

  • Sleeping problems
    Lack of sleep and a poor sleeping pattern can increase emotional stress levels and your perception of pain. Sleep is also important for the recovery and healing of inflamed body tissues.

  Who is at risk?

  Anyone can have back pain, although there are a number of factors that can increase your risk. They include:

  • Your age
    You are most likely to have back trouble between the ages of 30 and 50.

  • Your fitness
    Back pain is more common among people who are not physically fit. If you are fit, your muscles will be strong and flexible and your bones will be stronger, too.

  • What you eat
    A diet high in calories and fat, combined with an inactive lifestyle, can lead to weight gain and obesity, which can put stress on your back.

  • Heredity
    Some causes of back pain, including disc disease, may have a genetic component.

  • Occupational risk factors
    Having a job that requires heavy lifting, pushing, or pulling, particularly when this involves twisting or vibrating the spine, can lead to injury and back pain. A desk job may also lead to or contribute to pain, especially if you have poor posture or sit all day in an uncomfortable chair.

  • Cigarette smoking
    Although smoking may not directly cause back pain, it increases your risk of developing low back pain. For example, smoking may lead to pain by blocking your body's ability to deliver nutrients to the discs of the lower back. Or, repeated coughing due to heavy smoking may cause back pain.

    If you're a smoker you may be less physically fit or healthy than a non-smoker, which increases the likelihood you will develop back pain. Smoking can also slow healing, prolonging pain for people who have had back injuries, back surgery, or broken bones.