Sciatica: leg pain, causes, self-care and warning signs to know

Sciatica is a common cause of leg pain that starts in the lower back or buttock. This article explains what it is, what causes it, how it is managed and which signs need urgent care, using information from the NHS and MedlinePlus.

1. Introduction

Sciatica happens when the sciatic nerve is irritated or squeezed. This is the body's largest nerve, running from the lower back through the buttock and down the back of each leg ^{[1, 2, 3]}. MedlinePlus explains that sciatica is a symptom rather than a disease on its own, and the cause behind it needs to be found ^{[2, 3]}.

The NHS says sciatica usually improves within a few weeks to a few months, but it can last longer and may come back ^[1].

2. Causes and risk factors

The sources list these causes ^{[1, 2, 3, 4]}:

• A slipped disc. This is the most common cause. The soft cushion between two spinal bones, also called a herniated or prolapsed disc, bulges out and presses on a nerve ^{[1, 4]}.
• Spinal stenosis. This is a narrowing of the spinal canal, the channel that holds the nerves ^{[1, 2]}.
• Spondylolisthesis. A bone in the spine slips out of position ^{[1, 3]}.
• Injury, such as a back injury or a fracture of the pelvis ^{[1, 2]}.
• Piriformis syndrome, a pain condition involving a buttock muscle, and tumours ^[3].

In many cases no clear cause is found ^[2]. Slipped discs become more likely with age. The NHS adds that heavy lifting with poor technique, long periods of sitting or driving, being inactive, being overweight and smoking can all contribute to disc problems ^{[1, 4]}. MedlinePlus notes that men in their 30s to 50s are more likely to be affected ^[3].

3. Signs and symptoms

The typical signs are ^{[1, 2, 3]}:

• Pain in the buttock and the back of one leg, which may be sharp or burning and can reach the foot and toes.
• Tingling, numbness or weakness in the leg or foot.
• Pain that comes on suddenly or gradually and may get worse with movement, sneezing, coughing, straining, sitting or standing for a long time.

Back pain may also be present, but it is usually less severe than the leg pain. The NHS notes that back pain alone is not usually sciatica ^[1]. In some people the foot may catch on the ground while walking because of weakness ^[3].

4. Diagnosis and tests

A doctor will start with your symptoms and a physical examination. MedlinePlus says the doctor checks reflexes, muscle strength, feeling and movement of the back and legs, and may carry out a leg-raise test ^[3]. MedlinePlus says tests such as an X-ray or MRI are often unnecessary unless the pain is severe or lasts a long time ^[3]. The NHS says an MRI scan may be needed for a slipped disc if symptoms do not improve ^[4].

5. Treatment and management

Stay active

The NHS advises staying as active as you can and starting gentle exercise soon, rather than resting for long periods, even if movement hurts a little ^[1]. MedlinePlus agrees that prolonged bed rest should be avoided ^[3]. The NHS suggests heat packs on painful areas ^[1]. Ice for the first few days and then heat is also described ^[3].

Pain relief

A pharmacist or doctor can advise on pain relief that is safe for you. The NHS points out that some common painkillers may not help sciatica much, so ask before buying ^[1].

Physiotherapy and exercise

Exercises and stretches, with or without a physiotherapist, are a main part of care. The NHS says physiotherapy can include exercise advice and hands-on techniques ^[1]. In many areas you can refer yourself to NHS community musculoskeletal (bone, joint and muscle) services without seeing a GP first ^[1].

Specialist treatment

If pain is severe and other treatments have not helped, a hospital specialist may consider injections near the nerve, a procedure that seals pain signals in nearby nerves, or surgery to relieve pressure on the nerve ^{[1, 2, 3]}. Surgery is usually a last resort ^[3].

6. Prevention and self-care

MedlinePlus says prevention depends on the cause, and sciatica can come back ^[3]. The NHS suggests these steps to lower the risk ^[1]:

• Stay physically active.
• Lift heavy objects safely.
• Keep good posture when sitting and standing, and set up your computer workstation correctly.
• Keep to a healthy weight.
• Do not smoke.

MedlinePlus adds that keeping your back and core muscles strong helps, especially as you get older ^[3].

7. Special groups

Men in their 30s to 50s are more likely to develop sciatica ^[3], and slipped discs become more likely with age ^[1]. People who have back pain after a severe fall or blow, or who use steroid medicines, should tell a doctor early ^[3]. If you are unsure whether leg pain is sciatica, ask a doctor.

8. When to see a doctor

See a doctor if sciatica has not improved after a few weeks of home care, is getting worse or is stopping you carrying out normal activities ^[1]. MedlinePlus also lists back pain with a fever, pain after a severe fall or blow, pain that wakes you at night, weight loss you cannot explain, or weakness or numbness in the leg ^[3].

Some signs may mean a serious back problem that needs urgent hospital treatment. The NHS says to go to hospital immediately if you have ^[1]:

• Sciatica on both sides.
• Severe or worsening weakness or numbness in both legs.
• Numbness around the genitals or bottom.
• Difficulty starting to urinate, being unable to urinate or losing bladder control.
• Loss of awareness of bowel movements or loss of bowel control.

Do not drive yourself, and bring a list of your medicines. Tell your doctor about every medicine, supplement and treatment you use.

In an emergency, call your local emergency number (112 in India, 911 in the United States).

9. Conclusion

Sciatica is leg pain, tingling or weakness caused by pressure on or irritation of the sciatic nerve, most often from a slipped disc. Most people improve within weeks to months with gentle activity, exercises and sensible pain relief, though it can return. Specialist treatment is considered only for severe, lasting cases. Knowing the urgent warning signs, such as bladder or bowel changes and numbness around the genitals, are important reasons to seek hospital care at once.