Low Back Pain

Reviewed/Revised Jan 2024
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The lower (lumbar) spine allows your body to turn, twist, and bend. It also gives strength for standing, walking, and lifting. The lower back is involved in almost all movement. Pain in the lower back is very common.

  • Low back pain is usually caused by lifting, exercising, falling, or being in a car crash

  • The most common cause of low back pain is muscle strain

  • Strengthening your stomach, hip, and back muscles can help prevent low back pain

  • You can treat low back pain by avoiding activities that stress your back, taking pain relievers, and using cold or heat on your back, but low back pain usually heals on its own

  • Older adults with low back pain without an obvious cause or with the "warning signs" below may need to be seen by a doctor

When should I see a doctor?

See your doctor right away if you have low back pain and any of these warning signs:

  • Numbness

  • Weakness in one or both legs

  • Problems with urinating or passing stool (poop)

  • Fever

  • Light-headedness or fainting

  • Severe pain anywhere in your belly

See your doctor within a day if you have low back pain and any of these warning signs:

  • History of cancer

  • Weight loss

  • Severe pain at night

  • You’re age 55 or older and there’s no obvious reason, such as an injury causing your pain

  • You’re at increased risk of infection because of medicines you take, recent surgery or injury, drug use or because you have HIV or AIDS

If your pain isn't severe and you have no warning signs, you can wait several days to see a doctor.

What causes low back pain?

Doctors may not always be able to tell what's causing your low back pain. The most common cause of low back pain is:

  • Muscle strain or ligament sprains (ligaments are short, tough bands of tissue that hold your bones together at a joint)

This may happen on one or both sides of your back. Your pain gets worse with movement and better with rest.

Other common causes include:

  • Nerve compression (when something pushes on a nerve), which can happen with conditions like osteoarthritis or a herniated disk

  • Lumbar spinal stenosis—the spinal canal, the passageway in the spine that the spinal cord runs through, becomes too small

  • Spondylolisthesis, where a back bone (vertebra) slips forward over the one below it

  • All-over body pain (such as occurs in fibromyalgia) may also affect the lower back

A disk is the spongy tissue between back bones (vertebrae) that lets your spine bend. When a disk is torn or squeezed, jelly-like material can bulge out (herniate) and can put pressure on a nerve. Coughing or sneezing may make nerve compression pain worse.

Lumbar spinal stenosis is a common cause of low back pain in older adults.

Your pain may be worse if you:

  • Lift something heavy the wrong way

  • Have obesity

  • Are very tired

  • Have poor posture (you don’t stand up straight)

  • Don’t have good muscle strength in your back, stomach, and hip muscles (core muscles)

What is sciatica?

Sciatica is pain caused by pressure on the sciatic nerve. The sciatic nerve is the largest nerve in the back. It runs from your lower spine down the back of your leg. Any cause of low back pain may result in sciatica.

Usually sciatica affects only one side. You may feel pins-and-needles, tingling, or numbness in part of your leg. You may have achy or shooting pain down the back of your leg to your knee or to your foot. Continued pressure on the nerve is serious and may lead to long-term weakness and numbness in your leg.

What will happen at my doctor visit?

Your doctor will ask questions about your symptoms and health history and do a physical exam.

In certain cases, your doctor may do tests such as x-rays, MRI (magnetic resonance imaging), CT (computed tomography) scan, or electromyography and nerve conduction studies.

You don't always need x-rays or an MRI when you have back pain.

How will my doctor treat low back pain?

Doctors base treatment on the cause of your back pain and how long it has lasted. But in general, most low back pain goes away with good home care.

  • If your pain is severe, you may need to rest in bed for a day or two

  • Too much bed rest is bad because it weakens your back muscles, which can make your pain worse

  • Light activity actually helps—ask your doctor what you should and shouldn't do

  • Apply heat or cold to the painful area—cold is best during the first 2 days after an injury, then use heat

  • When lying down, you may be more comfortable on your side with your knees bent

As soon as possible, your doctor will have you start doing mild exercises to strengthen your back. Stronger muscles keep your back stable so it will hurt less. You may be sent for physical therapy. Therapists can teach you the back exercises so you can do them on your own. They can also teach you how to lift and move properly so you can work safely.

If doctors are sure the pain isn't due to nerve compression or osteoarthritis, you may try:

  • Massage

  • Treatment by a chiropractor

For long-lasting pain, doctors may suggest:

  • Losing weight

  • Transcutaneous electrical nerve stimulation (TENS), an at-home electrical therapy that gives you a gentle tingling feeling and can be used several times per day—your doctor will send you to a physical therapist to help you learn how to use this device

  • Surgery

There are many different types of back surgery. Typically, doctors recommend surgery only when you have signs of severe nerve compression or if your pain is very bad and isn't helped by all the other treatments.

How can I prevent low back pain?

  • Do exercises to stretch and strengthen your stomach, hip, and back muscles

  • Keep your back straight when standing and sitting (slouching stresses your back)

  • Sit with your feet on the floor, not with your legs crossed

  • Don't stand or sit for long periods

  • When lifting items, lift with your legs, not your back

Exercises to Prevent Low Back Pain

Pelvic Tilts

Lie on the back with the knees bent, the heels on the floor, and the weight on the heels. Press the small of the back against the floor, contract the buttocks (raising them about half an inch from the floor), and contract the abdominal muscles. Hold this position for a count of 10. Repeat 20 times.

Abdominal Curls

Lie on the back with the knees bent and feet on the floor. Place the hands across the chest. Contract the abdominal muscles, slowly raising the shoulders about 10 inches from the floor while keeping the head back (the chin should not touch the chest). Then release the abdominal muscles, slowly lowering the shoulders. Do 3 sets of 10.

Knee-to-Chest Stretch

Lie flat on the back. Place both hands behind one knee and bring it to the chest. Hold for a count of 10. Slowly lower that leg and repeat with the other leg. Do this exercise 10 times.

Sitting Leg Stretch

Sit on the floor with the knees straight but slightly flexed (not locked) and the legs as far apart as possible. Place both hands on the same knee. Slowly slide both hands toward the ankle. Stop if pain is felt, and go no farther than a position that can be held comfortably for 10 seconds. Slowly return to a sitting position. Repeat with the other leg. Do this exercise 10 times for each leg.

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