A GP will typically see at least one patient with back pain each day. Most cases are non-specific low back pain with no identifiable cause. Less commonly, back pain can be the presenting complaint of an underlying pathology.
Acute back pain usually resolves within a week or so, but tends to recur. In some patients, it can become chronic.
History
Taking a good history is as important in the first presentation as in subsequent consultations if symptoms worsen, do not improve or new symptoms emerge.
Ask patients about current pain symptoms – onset, possible triggers, duration, aggravating and relieving factors, daily variation and pain in other areas. Ask about the impact pain has on daily activities, social functioning and work. Look for red flags (see box right), relevant comorbidities (ulcerative colitis or malignancy) and history of similar symptoms.
Consider psychological factors – ‘yellow flags’ – including lack of support, misconceptions about back pain, social isolation and mental health problems.1 Important work-related ‘blue flags’ include job dissatisfaction and claims for compensation and benefits. These factors can impede recovery from acute back pain and lead to chronic pain.
Examination
In the absence of pointers from the history for nerve root compression, malignancy, infection, fracture or inflammatory disease, evidence for the benefit from clinical examination is unclear. But, not examining the patient might leave the impression that their problem is not taken seriously. The focus of a physical examination should be on:
- site and source of pain – spinal or abdominal referred pain, spinal level of symptoms, possible specific structure such as facet joint pain, and pain in other joints such as the hips
- neurological deficits – paraesthesia, reduced joint reflexes or motor power deficit
- red flag signs.
The correct method to palpate the spine is with the patient prone with arms folded under the head and a pillow under the abdomen.
Nerve root pain (also known as sciatica) occurs when the sciatic nerve becomes trapped or irritated either in the lumbosacral spine or the muscles of the lower back or buttock. The straight leg raise test is useful to help confirm radiculopathy and assesses the L5, S1, and S2 nerve roots. The test is positive if pain occurs in the distribution of the sciatic nerve when the straight leg is raised to between 30° and 70°. A prolapsed intervertebral disc should be suspected when pain occurs in the affected leg when the unaffected leg is raised.
A rare but important cause of back pain is spinal cord compression which is most common in the thoracic spine. Compression at this level above L2 causes upper motor neurone signs that include increased tone in the limbs, hyperreflexia and upwards plantar reflexes. Cauda equina syndrome is compression of the spinal cord below the level of the L2. It causes lower motor neurone signs which include reduced tone in the limbs, absent or reduced reflexes and downwards plantar reflexes. This is a neurological emergency.
Investigations
If there is no identifiable cause for back pain, careful history and relevant examination should be sufficient to confirm the diagnosis of non-specific low back pain, without investigations. The duration of pain in itself is not an indication for investigations. There is no evidence that X-ray or MRI scans change the outcome in the absence of clinical suspicion. MRI scans find bulging, herniated and degenerative discs in lots of asymptomatic adults. These expensive tests can be unnecessarily alarming, risk medicalising the problem and expose the patient to radiation.
A full blood count is not useful for identifying serious causes in the absence of clinical suspicion.
Measuring the ESR or plasma viscosity are the best tests for excluding malignancy or ankylosing spondylitis but their usefulness and relevance will again rely on the clinical findings because of their low specificity.
Management
In managing back pain the goals are to relieve pain and allow the patient to return to usual activities. Physical activity is crucial and should involve simple adaptations such as walking more – not heavy exercises. Giving an advice leaflet about low back pain can help to address misconceptions, reduce anxiety and improve satisfaction with care.
Paracetamol and NSAIDs should be used as first-line analgesics. Although evidence on the effectiveness of opioids is weak, both European and NICE guidelines support the use of weak opioids as an alternative treatment option when other analgesics are ineffective or contraindicated.2,3
Sickness absence from work for back pain should not be encouraged. But, a brief time off may help the patient avoid the stresses of work in the short term.
Guidelines do not support the use of interferential therapy, laser therapy, lumbar supports, shortwave diathermy, therapeutic ultrasound, thermotherapy, traction, or transcutaneous electrical nerve stimulation.2,3,4
If back pain persists after four to six weeks, you should reassess – exploring factors that increase the risk of developing chronic back pain. Patients would benefit from referral for physiotherapy if they have not returned to normal activities at this time.
For back pain lasting up to a year, patients who have not been helped by one course of a physical treatment should be offered a further course of a different physical treatment. These patients should also be offered information and reassurance about back pain, correcting misconceptions, treating mental health problems, avoiding inactivity and setting realistic goals.
Patients with prolonged and recalcitrant symptoms of pain or distress should be referred for an intensive programme of combined physical and psychological treatment. The Expert Patient Programme is a recent government initiative for patients with chronic pain, consisting of six weekly sessions. The evidence suggests that these courses are effective.
Red flags in back pain
- Younger than 20 years or over 55
- A history of malignancy
- A recent history of trauma
- Constant progressive pain
- Immunosuppression or HIV
- Neurological symptoms
- Recurrent or prolonged use of corticosteroids
- Structural deformity of the spine
- Substance misuse
- Systemic symptoms
- Thoracic pain
- Unexplained weight loss
Clinical tips for back pain |
|---|
| Back pain can be confined to the back, associated with leg pain or present with only leg pain. |
| Some 98% of clinically important disc herniations occur at the L4-L5 and L5-S1 disc levels. So neurological examination should focus on the L5 and S1 nerve roots. |
| Consider vascular-related leg symptoms such as gluteal or calf claudication in patients with leg pain. The intervertebral disc can prolapse simply after bending or lifting. |
| Analgesics are often more effective taken regularly rather than ‘as required’ |
| There is no need to wait until pain has completely gone before resuming usual activities and work. |
Dr Majid Artus is a GP clinical lecturer with an interest in back pain at Keele University, and Arthritis Research UK research fellow
References
1 Kendall NAS, Linton SJ and Main CJ. Guide to assessing psychosocial yellow flags in acute low back pain: risk factors for long-term disability and work loss. Accident Rehabilitation and Compensation Insurance Corporation of New Zealand and the National Health Committee. Wellington, New Zealand, 1997
2 van Tulder M, Becker A, Bekkering T et al. Chapter 3. European guidelines for the management of acute nonspecific low back pain in primary care. Eur Spine J, 2006;15 Suppl 2:S169-S91
3 NICE. Osteoporosis - secondary prevention including strontium ranelate: guidance. TA161. 2008
4 Royal College of General Practitioners. Clinical Guidelines for the management of Acute Low Back Pain. London: Royal College of General Practitioners, 1996 and 1999.
