In a 1998 survey in Great Britain, one in 12 adults aged 25–44 years reported having back pain lasting over 1 year.1 Although 90% of patients with non-specific back pain stop consulting within 3 months, only 25% will have completely recovered after 1 year. Approximately 6% will go on to become chronically disabled.2
A key role of a GP should be to help reduce the number of patients presenting with acute lower back pain from going on to develop chronic pain, disability and loss of work. Unfortunately, back pain, being a symptom rather than a disease, suffers from a lack of understanding of its mechanism and a lack of evidence as to which intervention helps a particular patient. However, an escalation of back pain research and a shift in emphasis towards trying to identify early risk factors for chronic pain and disability have the potential to improve GP care and patients' outcomes, particularly outcomes for those who may be vulnerable to developing chronic back pain.
Patients presenting with acute back pain should initially be assessed into one of three groups:3 non-specific low back pain (the vast majority), those with possible nerve root problems and lastly those with red flags for possible serious spinal pathology. These red flags include: age of onset <20 or over 55 years, past history of carcinoma, systemically unwell or weight loss, structural deformity, constant progressive non-mechanical type pain and widespread neurological symptoms. For the rest of this editorial we shall be concentrating on non-specific low back pain.
A GP should assess which patients presenting for the first time may go on to have chronic back pain, become disabled or stop work. There are screening tools, prognostic markers and risk factors to help, but individually they lack sensitivity and specificity.4,5 GPs can bring together various pieces of information to come up with a working hypothesis about the prognosis for a patient consulting for the first time.
Yellow flags,6 used to indicate psychosocial risk factors, have reasonable validity in predicting poorer outcomes. Factors such as a person's belief that the back pain is serious (catastrophic thinking), fear avoidance behaviour, low mood and passive coping strategies may all be moderate predictors of chronicity. The above should be considered together with risk factors for time off work, such as job dissatisfaction, previous sick certification or compensation claims.
An interesting paper in this month's Journal increases our understanding of how to predict which patients are more likely to develop chronic back pain. Jones and colleagues7 show that patients with passive coping strategies have a worse prognosis, regardless of the initial severity of pain and disability, that is, passive coping strategies precede the persistent symptoms. Jellema and colleagues' (submitted for publication in the BJGP, 2006) compares four instruments in the prediction of an unfavourable course of low back pain: two existing screening questionnaires, risk estimation by GPs and a new prediction tool they have developed (and therefore not yet validated in other settings). Reassuringly, risk estimation of poor prognosis by the GP performs as well as or more favourably than other instruments and for now seems to be the best available option.
Examination can be helpful in suggesting abnormal illness behaviour — such as an exaggerated response to superficial palpation or inconsistent findings.8 These signs are not necessarily to ‘catch a patient out’ but rather to suggest to the GP that back pain may be a sign of some other psychological or social distress that needs to be explored and perhaps treated. This does not imply the patient's experience of back pain is not real — it is — only that thinking in terms of mind–body dualism is not helpful here.
Timing of consultations is important. The length of time a person is off work can be used as a prognostic marker for the risk of developing chronic pain and disability. After a patient has been off work for 4 weeks, there is a 10–20% chance that they will not return to work within 1 year. If they are off work for more than 3 months, there is only a small chance they will ever return to work.9 It may help to review more frequently those patients who, on the basis of yellow flags, the GP suspects will have a worse prognosis.
The critical period seems to be in the first 4 weeks of presentation when the following treatment and advice may be appropriate:10
- giving information about back pain and reassurance;
- controlling symptoms including the use of regular analgesia, anti-inflammatories and the short-term use of muscle relaxants;
- advice to keep active and continue normal daily activities if possible;
- minimising time off work, depending on the nature of their job — specifically not always waiting until they are completely pain free.