Acute-subacute low back pain
Definition and prevalence
Low back pain is pain located in the lumbar and/or sacral regions of the spine, covering the region between imaginary transverse lines through the tip of the last thoracic spinous process and through the posterior sacrococcygeal joints.
Low back pain can be classified as:
- acute - present for 4 weeks or less
- subacute – present 5-12 weeks after injury
- persistent (chronic) - present ≥ 12 weeks after injury.
Episodes of acute and subacute low back pain are common. In most cases a specific diagnosis is unable to be made. Usually, symptoms are attributed to soft tissue structures of the low back. Many factors may contribute to the development of low back pain.
Almost everyone will experience an episode of low back pain at least once in their lifetime. Most will recover or have reduced disability or reduced pain intensity within three months of symptom onset. After three months the recovery rate slows.
Clinical Practice Guideline – acute-subacute low back pain
Acute-subacute low back pain fact sheet
Low back pain evidence update report
Low back guideline review report
- Take a history
- Conduct a physical examination
- Assess for red flags
- Patients with uncomplicated non-specific low back pain do not initially require diagnostic imaging. Diagnostic imaging should be restricted to cases where red flags are indicated, where there is an absence of expected improvement or the condition has deteriorated at reassessment
- Assess yellow flags as early as possible (within the first 4 – 6 weeks) and allow enough time during your consultation to explore any issues
- Consider all the circumstances of the worker including the work environment, workplace supports, the home situation and concerns about activities at home
- Consider the use of the Orebro questionnaire to assist you in appropriately identifying potential yellow flags
- Refer to an appropriate health professional to help manage yellow flags
- If workplace risks are identified, consider contacting the workplace, organising a case conference or recommending a Vocational Rehabilitation provider be engaged.
Provision of advice and reassurance
- Provide the worker with reassurance about their individual concerns
- Explain in as much detail as necessary the diagnosis and prognosis
- Support your advice with written material, Caring for your low back pain
- Encourage the worker to stay active and to gradually resume normal activity
- Discourage prolonged bed rest as this is associated with a delayed recovery
- Reassure the worker that low back pain usually resolves within a few weeks
- Advise the worker about workplace paced and graded activity.
Most cases of low back pain resolve in a few weeks. Most often the treatment of low back pain only requires simple measures, advice and reassurance. A combination of treatment approaches may be required to manage workers with low back pain, these include:
- physical therapy such as manipulation or a specific exercise program, with or without the application of superficial heat therapy
- the prescription of medication if necessary with the first choice being paracetamol
- advice, education, exercise and psychosocial intervention based on initial assessment findings
- a structured workplace intervention such as graded activity or a work site attendance for workers who have not returned to work after four weeks.
Treatment should be targeted at increasing a worker’s ability to perform their usual activities. Discuss and agree functional goals with the worker including how long and how often these goals should be undertaken.
Be aware of evidence-based risk factors that may influence prognosis. Some of these evidence-based factors are:
- symptoms of high pain intensity, disability, back related lower limb pain
- a previous episode of low back pain
- age – with older workers being more vulnerable
- a history of smoking
- chronic pain unrelated to low back pain
- high levels of distress
- a lack of pain-free days
- belief that on-going activity will lead to further harm
- expectations and perceived indicators of when it will be possible to return to work
- the presence of specific workplace factors (physically demanding work, longer hours, lack of supervisor support).
There are a number of monitoring methods which can be adpoted to assess a workers progress with recovery, these include:
- feedback from the worker, workplace or other health professionals
- clinical assessment
- return to work progress
- use of outcome measures.
There will be a percentage of workers who will continue beyond the 12 week point without having made a full recovery. It is important to remember that improvement at this stage is still likely to occur, however the management of chronic or persistent pain is different from acute and subacute low back pain.



















