Most cases of low back pain will resolve within four weeks using self care measures, although many people experience recurrences and may develop chronic back pain with acute episodes when it is worse.

There is also a risk of long-term pain and functional impairment, particularly in those who:

• Experience pain for longer than 12 weeks
• Try to cope by catastrophising about the future
• Adopt strategies such as avoiding work or movement because of fear of triggering pain
• Are very distressed about their situation.

Complications of low back pain include reduced productivity and loss of employment, plus a deterioration in mental health.

Sciatica is usually transient, with most patients recovering within a few weeks or months. Some groups have an increased risk of a poorer prognosis, namely:

• Women
• Individuals with psychosocial risk factors such as physically demanding work or working unsociable hours
• Those who initially experience a greater level of pain or functional impairment.

Recurrence is common, and the possible complications include those mentioned above for low back pain, plus permanent nerve damage – particularly if there is significant muscle wasting or loss of tendon reflexes – with a chance of sensory deficits and motor weakness.