Low Back Pain: Non-specific Low Back Pain, Assessment and Staying Active

Low back pain is a complaint that ranks high among the reasons people seek health care. By contrast, the information that circulates about low back pain often leaves the person more anxious and more inactive than they need to be. This article aims to explain low back pain in a calm voice, with the current clinical approach: what is known, what is uncertain, and what the person can do. The content is for information; it does not take the place of an assessment specific to the person.

How common is low back pain?

Low back pain is one of the common causes of disability worldwide; it creates a substantial burden both in health spending and in working days lost. Organisational sources that address work-related musculoskeletal disorders place the mid-back and low-back region at the centre of this picture.

This prevalence has a practical consequence: experiencing low back pain does not mean you are in an unusual or alarming situation. The large majority of complaints do not point to a serious structural problem and ease markedly over time.

What does “non-specific low back pain” mean?

In clinic, the large majority of low back pains are classified as non-specific low back pain. This phrase does not mean “the cause is unknown” or “it is not real”. It means this: there is no finding by which the pain can be attributed reliably to a single structure (a particular disc, joint or muscle), and a single mechanism is not enough to explain the picture.

This classification has two benefits:

• It reduces unnecessary intervention. The search for a single “faulty part” is, in most cases, a search that leads neither to imaging nor to a procedure.
• It directs management to the person. The focus shifts from repairing a structure to arranging loading, activity and capacity.

Separately from the non-specific picture, nerve-root signs radiating into the leg (the picture known as sciatica) and uncommon specific causes are addressed separately. Making this distinction is one of the first jobs of the assessment.

Factors that affect low back pain

It is usually not possible to reduce low back pain to a single cause. Headings that can contribute:

• Loading and sudden changes in loading. More than the weight itself, rapid increases that go outside what is habitual can trigger the picture.
• Physical activity level and capacity. Low general condition can lead daily loads to become relatively more demanding.
• Uninterrupted time spent in a position. Remaining in the same position for a long time — sitting or standing — can increase discomfort. For details specific to sitting, see the prolonged sitting and low-back health guide.
• Sleep duration and quality.
• Stress, workload and work-related psychosocial factors. High job demand, low decision latitude and little opportunity for a break are among known factors in work-related musculoskeletal complaints.
• Beliefs and behaviours related to pain. Avoiding movement may look relieving in the short term, but over time it can narrow the field of activity.

What does a physiotherapy assessment cover?

The aim of the assessment is to classify the picture and to plan a physiotherapy approach suitable for the person. The following headings are usually addressed:

• History: the onset of the complaint, its course, how it changes during the day, previous episodes
• Distribution of the signs: whether the pain radiates into the leg, descriptions of numbness, tingling or loss of strength
• Screening for warning signs: questions and examination findings aimed at ruling out uncommon but important pictures
• Movement and function: range of movement, the quality of the movement, bending, turning, sit-to-stand and walking
• Capacity: trunk and lower-limb strength, endurance, the response to loading
• Daily loading profile: work pattern, sitting time, carrying and lifting requirements, physical activity level, sleep
• The person’s aims: which activity they want to return to, what being unable to do restricts them most

The guidelines also include the use of risk-classification tools aimed at assessing the likelihood of the pain becoming persistent; this helps adjust the intensity of the approach to the person. Detailed information about the assessment process is on the low-back and mid-back health page. In pictures where movement quality and body perception stand out, a body awareness approach may be part of the plan.

Staying active

One of the headings that appear consistently in low-back-pain guidelines is supporting the person in staying active and in gaining self-management skill. Prolonged bed rest is outside this framework.

The evidence picture on exercise is as follows: in long-standing low back pain, exercise reducing pain compared with no treatment or usual care is supported by moderate-level evidence. The effect on functional limitation has been found smaller. The differences that appear when compared with other conservative approaches are small. Exercise is generally safe; the side effects reported are mostly temporary and mild effects such as muscle soreness.

The practical meaning of this is important: a clear superiority of any one exercise type over others has not been shown. So rather than looking for “the correct exercise list for the low back”, it is more meaningful to build a programme that the person can sustain and increase gradually. The World Health Organization recommends at least 150 minutes of moderate-intensity physical activity per week for adults; this general framework also forms a ground for low-back health. How the programme is structured is addressed on the exercise and physical activity page.

Load management

Load management describes the third path between stopping the activity and forcing it:

1. Make the total load visible. On days when the pain increases, review not only a single movement but the load of the whole of that day (work, home, exercise, sleep).
2. Change a single variable. Increasing duration, intensity and frequency at the same time makes it unclear which change has what effect.
3. Allow time for adaptation. Tissues adapt to loading, but this adaptation takes place on a scale of days to weeks.
4. Create variety of positions. Moving during the day rather than remaining in the same position for a long time changes the distribution of load in the low-back region.
5. Do not narrow the field of activity. As the list of avoided movements lengthens, daily life also narrows; the aim is to shorten the list.

Practical ways to place movement in the working day are addressed in the active break and office ergonomics guides; the relationship of total sitting time to general health is addressed in the prolonged sitting guide. A low-back complaint is often described together with neck and shoulder complaints; for the counterpart of the same loading logic in the neck region, see the neck pain guide.

When should you see a health professional?

The following signs are uncommon in people who experience low back pain. They are listed here not to create anxiety, but to make clear the situations in which asking for assessment, rather than waiting, is appropriate.

Signs that require urgent assessment:

• Difficulty passing urine, or a newly appeared change in bladder or bowel control
• Newly started numbness or loss of sensation in the hip, groin and inner-thigh region (the sitting area)
• Loss of strength that appears in both legs together or is progressing
• A suddenly started change in sexual function

When these signs appear together or on their own, one should not wait and should go urgently to a health facility; these pictures cannot be managed through article content.

Other situations that need assessment without delay:

• Low back pain that started after a marked trauma such as a fall or a blow
• Fever, unexplained weight loss, continuous pain that does not ease with rest through the night, general fatigue
• Newly started low back pain in the presence of conditions such as a known history of cancer, long-term corticosteroid use, or osteoporosis
• Numbness, tingling or loss of strength radiating into the leg and gradually increasing

Situations in which making an appointment is reasonable:

• The complaint not easing as expected within a few weeks
• Pain that affects sleep, work or daily activities in a marked way
• Frequently recurring episodes and an increasing tendency to avoid
• Not being sure how to start; a structured assessment usually takes a faster path than weeks spent on trial and error

For information about the individual assessment process, see the low-back and mid-back health page. If any of the signs defined as urgent above are present, go first to the nearest health facility.