Chronic low back pain: causes, sciatica, diagnosis and treatment
Low back pain stays with many people in Portugal for months or years. This guide explains the causes, sciatica, warning signs, tests and treatments, and what a video consultation can do for you.
Low back pain (lumbago) is pain in the lower back, between the lowest ribs and the buttocks, and it is considered chronic when it lasts more than 12 weeks. In the national EpiReumaPt study, 26.4% of adults in Portugal had low back pain confirmed by a rheumatologist. Most episodes improve with movement and the right support. If the pain persists, spreads down your leg or wakes you at night, a video assessment with our doctor is a good first step. Fever, worsening weakness or changes in passing urine are warning signs that need immediate assessment.
Definition
What low back pain is and when it becomes chronic
Low back pain is pain or discomfort in the lumbar region, below the lowest ribs and above the buttocks, with or without pain in the legs.
It is classified by how long it lasts: acute up to six weeks, subacute between six and 12 weeks, and chronic (or persistent) when it lasts more than 12 weeks. According to the Medicines Information Centre of the Portuguese Pharmaceutical Society (Ordem dos Farmacêuticos), low back pain affects up to 80% of people at some point in their lives and is one of the leading causes of disability.
- Non-specific low back pain. About 80 to 90% of cases, with no specific identifiable cause.
- Herniated disc and sciatica. A disc presses on a nerve root and the pain travels down the leg.
- Degenerative changes. Wear of the discs and spinal joints (spondylosis) and narrowing of the spinal canal (spinal stenosis).
- Inflammatory back pain. Prolonged stiffness on waking that eases with movement, mainly in younger people; it may point to spondyloarthritis.
- Serious causes. Fractures, infections or tumours are rare: fewer than 1% of people with low back pain have a serious cause.
National data
Low back pain in Portugal: what the numbers say
EpiReumaPt is the largest population study of rheumatic diseases carried out in Portugal, and low back pain comes first.
- 26.4% of adults had low back pain confirmed by a rheumatologist, the most common rheumatic disease in the study
- 10.4% reported active chronic low back pain: pain on the day of the interview and for 90 days or more
- 10,661 adults selected at random across the country
- OR 2.77 for anxiety symptoms in people with active chronic low back pain, compared with those without
Sources: Branco JC et al., RMD Open 2016;2(1):e000166 (EpiReumaPt); Gouveia N et al., Rheumatology International 2016;36(2):183-197.
The data were collected between September 2011 and December 2013 by the EpiReumaPt team of the Portuguese Society of Rheumatology, with support from, among others, the Directorate-General of Health (Direção-Geral da Saúde). After low back pain came periarticular diseases (15.8%) and knee osteoarthritis (12.4%).
In the analysis focused on chronic low back pain, Nélia Gouveia, Jaime C. Branco, Helena Canhão and colleagues found that people with active pain were more likely to have anxiety symptoms (OR 2.77), early retirement due to illness (OR 1.88) and more medical appointments. The authors conclude that active chronic low back pain is highly prevalent in Portugal and is associated with disability and high use of healthcare.
Another analysis of the same study (Pina Gonçalves N et al., ARP Rheumatology 2023) estimated the prevalence of rheumatic and musculoskeletal diseases not yet diagnosed at 29%, linked to poorer quality of life, poorer physical function and more anxiety symptoms.
Source: Pina Gonçalves N et al., ARP Rheumatology 2023;2(1):7-16.
Causes and risk factors
Causes of back pain and risk factors
For most people, back pain results from several factors together rather than a single injury.
- Sedentary work and many hours sitting.
- Heavy physical work: jobs that involve repeated lifting or bending.
- Overweight and obesity, linked to chronic low back pain in the Portuguese study.
- Anxiety, depression and other psychosocial factors, such as stress.
- Previous episodes of low back pain.
- Ageing: wear of the discs and joints, stenosis and vertebral fractures due to osteoporosis.
- Other rheumatic diseases and several conditions at once, also linked to chronic low back pain in EpiReumaPt.
- More rarely, inflammatory, infectious or tumour-related causes, or problems outside the spine, such as kidney disease or an aortic aneurysm.
Sources: Ordem dos Farmacêuticos, CIM — Low back pain (2025); Gouveia N et al., Rheumatology International 2016.
Pain that travels down the leg
Lumbosciatica and sciatic pain: when the pain travels down the leg
When low back pain spreads through the buttock and down the back of the leg, it is called lumbosciatica. The leg part is sciatica.
Sciatica is pain along the sciatic nerve, which leaves the lower back, passes through the buttock and runs down the leg. It usually affects one side only and may come with tingling, numbness or weakness in the leg or foot. The most common cause is a herniated disc pressing on a nerve root; wear of the spine, with bony outgrowths, and narrowing of the spinal canal can also cause it.
- How it shows: sciatic pain can be severe and often gets worse with coughing, sneezing or bending forward.
- Course: in most people it improves without surgery; a large share of people with back pain recover in about six weeks.
- Tests: if symptoms last more than six weeks, the doctor may order imaging or nerve studies.
- Surgery: it is considered if sciatica is severe and persistent, with weakness or loss of sensation, and it is urgent if there is loss of bladder or bowel control.
In lumbosciatica, medication helps less: according to the Medicines Information Centre, anti-inflammatories relieve chronic low back pain without radicular symptoms but not with them, and epidural steroid injections give only a slight, short-term reduction in pain.
Sources: MSD Manual — Sciatica; MSD Manual — Herniated disc; Ordem dos Farmacêuticos, CIM — Low back pain (2025).
The MRI report
Herniated disc and lumbar spondylosis: what they mean
Many people arrive at the consultation with an MRI report that mentions a herniated disc, a protrusion or lumbar spondylosis. These terms do not always explain the pain.
Herniated disc
A herniated (slipped) disc happens when the tough outer layer of an intervertebral disc tears and its jelly-like centre bulges out. Most occur in the lower back, mainly between the ages of 30 and 50. It may cause no symptoms or, if it presses on a nerve root, cause sciatic pain, numbness and weakness. After one to two years, recovery is similar in people who had surgery and those who did not.
Lumbar spondylosis
Lumbar spondylosis is wear (osteoarthritis) of the discs and small joints of the lumbar spine, which increases with age. Bony outgrowths may form and, in more marked cases, press on nerve roots or narrow the spinal canal (lumbar stenosis), a common cause of back and leg pain in older people.
MRI scans often show bulging discs and signs of wear in people with no pain at all. That is why the doctor always interprets the images together with the symptoms and the clinical examination.
Sources: MSD Manual — Herniated disc; MSD Manual — Low back pain.
Symptoms
Symptoms of low back pain and warning signs
Common symptoms
- Dull, burning or stabbing pain in the lower back.
- Stiffness on waking or after sitting for a long time.
- Pain that spreads to the buttock, thigh or leg, with tingling or numbness.
- Difficulty bending, lifting or walking for long.
- Disturbed sleep and tiredness because of the pain.
Other signs that warrant prompt medical assessment: severe night pain that does not ease with rest, unexplained weight loss, a history of cancer, long-term use of steroids, a weakened immune system or injecting drug use, and pain that has not improved after four to six weeks.
Sources: Ordem dos Farmacêuticos, CIM — Low back pain (2025); MSD Manual — Low back pain; gov.pt — Emergency contacts in Portugal.
Diagnosis
How low back pain is diagnosed
In most cases, a good medical history and physical examination are enough to assess acute low back pain.
| Step | What it shows |
|---|---|
| Medical history and physical examination | Type and duration of pain, radiation, mobility, strength, reflexes, sensation and risk factors |
| Pain and function questionnaires | Intensity, disability and emotional impact; used to track progress |
| Spine X-ray | Degenerative changes, alignment, fractures |
| Magnetic resonance imaging (MRI) | Discs, nerve roots, stenosis; indicated with warning signs or no improvement with treatment |
| Computed tomography (CT) | Bone detail, when MRI is not possible |
| Blood tests (ESR, CRP, full blood count) | Inflammation or infection |
| Electromyography | Nerve root damage |
According to the Medicines Information Centre, blood tests and imaging are usually not needed in acute low back pain: they are kept for when there are warning signs or the pain does not ease with conservative care.
Sources: Ordem dos Farmacêuticos, CIM — Low back pain (2025); MSD Manual — Low back pain.
Treatment
Treatment of acute and chronic low back pain
In the acute phase
- Stay active: prolonged bed rest does not help. With severe pain it may be unavoidable to stop for one or two days, but the aim is to return to your activities gradually.
- Understand the pain: non-specific low back pain generally has a good outlook, with clear improvement in four to six weeks.
- Local heat: may reduce pain and disability a little, for a short time.
- Medicines: only when non-drug measures are not enough, at the lowest effective dose and for the shortest possible time, on medical advice.
In chronic low back pain
- Supervised exercise and cognitive behavioural therapy: the first-line non-drug options in subacute and chronic low back pain. No type of exercise has proved superior; the best one is the one that suits you.
- Pain education and multidisciplinary rehabilitation, with physiotherapy when indicated.
- Psychological factors: mindfulness or progressive relaxation help you deal with what keeps the pain going.
- Medicines as an add-on: a second-line treatment, at a low dose and reviewed regularly; routine use of opioids is not recommended.
- Treating the cause: inflammatory back pain is treated in Rheumatology; nerve compression with neurological deficit, severe stenosis or instability may need a surgical assessment if conservative treatment fails.
Sources: Ordem dos Farmacêuticos, CIM — Low back pain: therapeutic interventions (2025); MSD Manual — Herniated disc.
Video consultation
How our online consultation helps with low back pain
Chronic low back pain is rarely resolved in a single consultation. Our musculoskeletal and pain assessment by video call gives you a plan and follow-up.
- Assessment: the doctor reviews the history of your pain, any spread to the leg, your work, sleep, medication and the treatments you have already tried.
- Warning signs: they identify what needs urgent examination and tell you clearly.
- Tests: they order blood tests, X-rays or an MRI only when justified, and go through any reports you already have with you.
- Plan: exercise, adjustments at work and to your sleep and, if needed, medication suited to your case.
- Follow-up: review appointments to measure how your pain and function are changing and to adjust the plan.
- Referral: when needed, our doctor refers you to Rheumatology, Physical and Rehabilitation Medicine, Orthopaedics, Neurosurgery, physiotherapy or psychological support.
Some cases need an in-person examination of the spine; when that happens, the doctor will say so clearly and set out the next step. Book your musculoskeletal and pain assessment here.
Do not wait
Why it is worth having back pain assessed early
Early assessment makes it possible to rule out serious causes, find the likely source of the pain and start the right treatment before an acute episode becomes chronic.
- Becoming chronic: repeated episodes and persistent pain.
- Nerve damage: lasting weakness or loss of sensation if compression is not treated in time.
- Loss of mobility and strength, with a higher risk of falls.
- Inability to work: in the national study, active chronic low back pain was associated with early retirement due to illness.
- Anxiety, depression and insomnia, which make the pain worse.
- Unidentified disease: infection, fracture, tumour or inflammatory disease.
- Long-term use of painkillers and their side effects.
The EpiReumaPt authors call for more awareness of these conditions and more resources for treating them; the 2023 analysis adds that earlier identification brings personal and social benefits.
Sources: Branco JC et al., RMD Open 2016; Gouveia N et al., Rheumatology International 2016; Pina Gonçalves N et al., ARP Rheumatology 2023.
Prevention
How to prevent new flare-ups of low back pain
- Stay physically active: the World Health Organization recommends that adults do at least 150 minutes of moderate-intensity physical activity a week.
- Avoid staying in the same position for long and take regular breaks to walk.
- Adapt your workstation: chair, screen height and the way you lift heavy things.
- Look after your sleep and mental wellbeing.
- A healthy weight and stopping smoking are good for your health in general, although there is little evidence that, on their own, they prevent new flare-ups.
Sources: Ordem dos Farmacêuticos, CIM — Low back pain (2025); World Health Organization — Physical activity.
Care in Portugal
Have your low back pain assessed by a doctor
A video consultation lets a doctor assess your pain, rule out warning signs and set a plan with follow-up.
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Back pain for more than a few weeks?
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Sources
Sources for this article
Sources checked on 18 October 2026.
This article explains low back pain, sciatica, warning signs and treatment options. It does not recommend medicines or doses; that decision is for the doctor, after assessing each case.
Questions
Frequently asked questions about low back pain
When should I see a doctor about low back pain?
If the pain has not improved after four to six weeks, spreads down your leg, wakes you at night, or comes with tingling or unexplained weight loss, book an assessment; our video consultation is a simple way to start. Fever, loss of bladder or bowel control, numbness in the genital area or worsening weakness are warning signs and need immediate assessment.
Do I need an MRI of my spine?
Not always. Without warning signs, imaging is usually not needed at first. It is ordered when there are warning signs, a suspected trapped nerve or pain that does not improve with conservative treatment.
Can chronic low back pain be cured?
It often improves a lot with supervised exercise, rehabilitation and, if needed, medication, but it may require long-term follow-up.
Does sciatic pain go away on its own?
In most people, yes: sciatic pain tends to improve without surgery within a few weeks. If it lasts more than six weeks or is very severe, a doctor should assess it; worsening weakness or loss of sensation needs immediate assessment.
Which doctor should I see for back pain?
Start with our musculoskeletal and pain assessment by video call. Our doctor assesses your pain, orders the tests you need and, when justified, refers you to Rheumatology, Physical and Rehabilitation Medicine, Orthopaedics or Neurosurgery.
How many people in Portugal have low back pain?
In the national EpiReumaPt study, 26.4% of adults had low back pain and 10.4% reported active chronic low back pain, present for 90 days or more.
