Sciatica and nerves
Sciatica links lower back trouble to pain in one leg
Pain that runs from your lower back into a leg often comes from an irritated nerve, and it usually improves over weeks to months [1]. A few warning signs need emergency care right away [1].
Key points
- Sciatica happens when the sciatic nerve is irritated or squeezed, and it usually gets better in a few weeks to a few months [1].
- A herniated disk is the most common cause of sciatica, and spinal stenosis and slipped vertebrae can cause similar pain [1].
- Numbness around the genitals or anus, or new bladder or bowel trouble, needs emergency care [1].
- Back pain with fever, chills, or unexpected weight loss is a reason to call your doctor [2].
- Staying active is a first-line approach for leg pain that starts in the back [3].
The sciatic nerve sends pain from the lower back down one leg
Sciatica happens when the sciatic nerve, which runs from your lower back to your feet, is irritated or compressed [1]. It usually affects your bottom and the back of one leg, and often the foot and toes [1]. You may have back pain too, but it is usually not as bad as the leg pain [1].
- A sharp, burning pain down the back of the leg [1].
- Pain that gets worse when you move, sneeze, or cough [1].
- A start that is sudden or slow [1].
- Numbness, tingling, or weakness that reaches the foot, which can happen even without back pain [2].
Doctors also use the term lumbar radiculopathy for pain that spreads from the lower back into the leg because a nerve root is compressed or irritated [4]. It is most often connected with a herniated disk or wear-related changes in the spine [4].
Spinal stenosis and slipped vertebrae can press on nerves in the lower back
| Cause | What happens |
|---|---|
| Herniated disk | The soft cushion between spine bones pushes out and presses on a nerve. It is the most common cause of sciatica [1][2]. |
| Spinal stenosis | The space where nerves pass narrows. Bone spurs and thickened ligaments can add to the narrowing [1][2]. |
| Spondylolisthesis | One spine bone slips forward on another. Too much slippage can press on spinal nerves [1][2]. |
| Facet joint wear | When disks collapse, the small joints at the back of the spine can rub, causing pain and stiffness [2]. |
| Compression fracture | Weak bones can break after minor trauma, such as a ground-level fall. This is a common cause of back pain in older adults [2]. |
| Abnormal spine curve | It can cause back pain, and possibly leg pain, weakness, or numbness if nerves are pressed [2]. |
Age-related changes can start in your 30s or even earlier [2]. They do not keep most people from living generally pain-free lives [2]. Some people with disk tears have no pain at all, and it is not clear why others do [2]. Smoking has been found to speed up disk wear [2].
When to get care
Numbness around the genitals or bowel and bladder changes can signal a serious back problem
These symptoms could point to a serious back problem that needs hospital treatment as soon as possible [1]. They need emergency care [1].
- Weakness or numbness in both legs that is severe or getting worse [1].
- Numbness around or under your genitals, or around your anus [1].
- Trouble starting to pee, being unable to pee, or losing control of your bladder, when this is not normal for you [1].
- Not noticing when you need to poop, or being unable to control it, when this is not normal for you [1].
Do not drive yourself to the emergency room. Ask someone to drive you or arrange an ambulance [1].
If you think you may have a medical emergency in the United States, call 911 or go to the nearest emergency room.
Your primary care doctor should hear about back pain that lingers or comes with fever
Call your doctor if back pain does not get better within a few weeks, or if it comes with fever, chills, or unexpected weight loss [2]. This applies whatever your age or symptoms [2].
- Pain that is always present, whatever your activity level or position [2].
- A history of cancer [2].
- Vascular or arterial disease, meaning a problem with your blood vessels. Some causes of back pain can be serious [2].
- Sciatica that has not improved after a few weeks of home treatment, or that stops you doing normal activities [1].
Pain that spreads from the back into the buttock or outer hip but not down the leg is a different pattern from sciatica [2]. Back pain that comes and goes, with good days and bad days, is another pattern [2].
Your doctor examines your reflexes and strength to check the nerves in your legs
Your doctor will ask about your symptoms and medical history, then examine your back [2]. They may press on different areas, ask you to bend in several directions, and check reflexes at your knees and ankles along with strength and sensation [2]. Imaging, particularly MRI, can show whether a nerve root is involved [4].
- Where the pain goes: back, buttock, leg, foot, or toes [1].
- Whether leg pain or back pain is worse [1].
- What makes it worse, such as moving, sneezing, or coughing [1].
- Whether it began suddenly or slowly [1].
- Any numbness, tingling, or weakness [2].
- Whether lying down helps [2].
- Whether pain is constant or comes and goes [2].
- Any history of cancer or vascular disease [2].
- Any earlier episodes of sciatica [1].
- Any change in bladder or bowel control [1].
Before you go
Note whether the pain is there whatever you do or position you take, because constant pain is one reason to talk to your primary care doctor [2].
Guidelines for lumbar radiculopathy recommend staying active as first-line care
Current guidelines list patient education, staying active, manual therapy, and anti-inflammatory painkillers as first-line treatments for lumbar radiculopathy [3]. For sciatica, the self-care steps below are meant to relieve pain and speed recovery [1].
- Carry on with normal activities as much as you can [1].
- Start gentle exercise as soon as you can, since anything that gets you moving can help [1].
- Hold heat packs on the painful areas [1].
- Ask a pharmacist about painkillers. It is not clear how much anti-inflammatory drugs such as ibuprofen help with sciatica [1].
- Avoid sitting or lying down for long periods. Even if moving hurts, it is not harmful and can help you get better faster [1].
Trials of manual therapy, nerve mobilization, and exercise reported short-term gains in pain and function [4]. The evidence is limited, and long-term follow-up is rare [4]. If pain is severe and other treatments have not helped, you may be referred to a specialist for options such as an epidural injection [1].
Epidural steroid injections tend to help most in the short term, with effects fading after months [5]. Disk-related nerve pain can also improve on its own over time [5]. One review found that injections given at the tailbone and injections aimed at the nerve root gave comparable pain relief and function at short and intermediate follow-up [6]. Another review found that nerve-root-targeted injections gave greater short- and intermediate-term pain and disability improvement than injections placed between the back bones [5].
Sciatica can return [1]. Safe lifting technique, good posture, and not smoking may lower the chance of that [1].
Sources
- Sciatica nhs.uk
- Low Back Pain orthoinfo.org
- Development and Content Validation of an Exercise-Based Framework for the Management of Lumbar Radiculopathy Physiotherapy research international : the journal for researchers and clinicians in physical therapy
- Evidence-Based Conservative Treatment Strategies for Lumbar Radiculopathy: A Systematic Review Cureus
- Effectiveness of epidural steroid injections in the treatment of lumbar radiculopathy: a systematic review and meta-analysis Frontiers in pain research (Lausanne, Switzerland)
- Route or reach? Caudal epidural versus nerve-root-targeted injection for lumbar radiculopathy: a systematic review of randomized controlled trials European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society
Not medical advice. This page is general education written from the sources above. It cannot diagnose a condition or replace a licensed clinician who knows your history. If you may be having an emergency, call your local emergency number or go to the nearest emergency department.