What Causes Low Back Pain?
Low back pain: An overview
The lower spine allows your body to turn, twist, and bend, and gives strength for standing, walking, and lifting. It is involved in almost all movement, so 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 and using cold or heat on your back, but low back pain usually heals on its own.
Low back pain without an obvious cause or with the warning signs below may need to be seen by a doctor.
When is the right time to see a doctor?
See your doctor right away if you have low back pain and these warning signs:
Numbness
Weakness in one or both legs
Problems with urinating or passing stool
Fever
Lightheadedness or fainting
Severe pain anywhere in your belly
See your doctor within a day if you have low back pain and 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 won't always be able to tell what's causing your low back pain. The most common cause is muscle strain or ligament sprains. 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 slips forward over the one below it
All-over body pain may also affect the lower back
A disk is the spongy tissue between back bones that lets your spine bend. When a disk is torn or squeezed, jelly-like material bulges out 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 people. Your pain may be worse if you lift something heavy the wrong way, are obese, are very tired, have poor posture, or don't have good muscle strength in your back, stomach, and hip muscles.
What is sciatica?
Sciatica is pain caused by pressure on the sciatic nerve. The sciatic nerve is the largest nerve in the back, running from your lower spine down the back of your leg. Usually sciatica affects only one side. You may feel pins and needles, tingling or numbness in part of your leg, or have an achy or shooting pain from the low back, through the buttock, 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 a 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, CT scan, or electromyography and nerve conduction studies.
How do doctors 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 weakens your back muscles, which can make your pain worse.
Light activity usually 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 two 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. You may be sent for physical therapy to learn how to do the back exercises and how to lift and move properly.
If doctors are sure the pain isn't due to nerve compression or osteoarthritis, you may try massage or treatment by a chiropractor. For long-lasting pain, doctors may suggest losing weight, transcutaneous electrical nerve stimulation, an at-home electrical therapy that gives you a gentle, tingling feeling, or 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 other treatments.
How can low back pain be prevented?
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.
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