Low back pain

Back pain is a general description for pain in the lower spine, the waistline and downward toward the tailbone. Back pain that lasts less than 12 weeks is considered acute. Back pain that lasts more than 12 weeks is considered chronic.


Anatomy
The backbone (spine) extends from the base of the skull to the buttocks. It's made up of more than 30 small bones called vertebrae, which are stacked on top of one another and held together by ligaments (tough nonelastic bands of tissue).
The vertebrae form a tunnel down the length of the back that houses the spinal cord and nerve roots. This tunnel is known as the spinal canal. The nerves branch off from the spinal cord and spread to the body through small openings in the vertebrae.

Between each vertebra are disks, composed of a jelly-like center with a tough, fibrous outer ring. These disks act as shock absorbers between the vertebrae and allow the spine to move.


Causes/associated factors
At least 80 percent of adults will be affected by low back pain at some time. About half of all people who have an initial acute episode of low back pain have a recurrence within one year. Most people recover quickly and completely from each episode.
The exact cause of low back pain is often unknown. The two most common culprits are problems with the ligaments and muscles or disks. Twisting, bending or lifting can strain or tear muscles and ligaments, causing immediate pain in the lower back.

As the disks age, they become more brittle and flat. When this happens, portions of the disks can bulge or even tear, possibly putting pressure on the spinal nerves. This type of back pain may be referred to as a ruptured, herniated or slipped disk (even though the disk can't slip out of place).

Other causes of back pain may include degeneration of the vertebrae, which may cause osteoarthritis, spondylolisthesis (slipping of one vertebrae onto the one below), spinal stenosis (narrowing of the spinal canal), fractures, infection or malignant tumors.

The risk of low back pain increases with:

repetitive back motion, such as lifting, bending and twisting
repetitive or prolonged vibration, such as driving a vehicle or using a jack hammer
regular long periods of sitting or standing
participating in high-risk sports, such as football, wrestling and skiing
lack of regular exercise, which contributes to overall poor muscle tone
poor posture
frequent coughing
smoking, which leads to spinal degeneration
obesity
osteoporosis (the loss of bone mass that leads to brittle bones)
degenerative changes related to aging
psychosocial factors, such as anxiety, depression or stress
family history of back pain

Signs/symptoms
Symptoms vary from person to person, but usually there's pain around the lower spine that's aggravated by certain motions. For sciatic nerve pain, there's usually mild to severe pain running through the buttocks, thigh and lower leg. This pain usually affects one leg. It may be accompanied by numbness, tingling and weakness.
Symptoms that may indicate a potentially dangerous underlying condition include:

pain after a major trauma
pain after any trauma in an older adult or someone who may have osteoporosis
pain in those who have a history of cancer
pain accompanied by fever, chills or vomiting
pain accompanied by unexplained weight loss
pain that's worse while lying down or during the night, especially if it keeps you from sleeping
pain unrelated to activity
Symptoms that require emergency evaluation include:

sudden loss of bladder control (incontinence or inability to empty the bladder)
sudden loss of bowel control (stool incontinence)
sudden numbness in the rectal, anal or pubic regions
sudden extreme weakness in the legs or extreme numbness or tingling
rapidly progressing leg weakness or numbness

Diagnosis
The doctor will ask questions about your medical history and do a physical exam, usually focusing on your spine and nervous system. Be sure to tell the doctor about:
any relevant family history
any past back injuries, conditions, surgeries or procedures
prescription or over-the-counter medications, including vitamins and other dietary supplements
typical work and recreational activities
The doctor may suggest various diagnostic tests, especially if the pain continues after four to six weeks of conservative treatment.

Blood or urine tests may provide evidence of infection, cancer or another illness.

X-rays can help rule out a fracture, tumor or infection.

Imaging studies such as magnetic resonance imaging or computed tomography can help the doctor study the affected area.

A bone scan may be done to help the doctor identify abnormal bone structure or functioning. With this procedure, a special radioactive dye is injected into a vein. The dye travels through the bloodstream to the bones, where it can be detected by a camera that scans the body.

Electromyography (EMG) may be done to measure electrical activity in the muscle in response to the signal sent by a nerve. This may be accompanied by a nerve conduction study, which measures how well an individual nerve sends an impulse to the muscle. These tests can help the doctor determine if the problem is related to nerve degeneration or nerve compression. These tests can be uncomfortable because a thin needle is inserted into the muscle to measure the electrical activity.

Discography (discogram) may be done to help identify which degenerated disks are causing back pain. With this procedure, a dye is injected into the jelly-like center of an intervertebral disk. This is followed by a computed tomography scan to help the doctor evaluate disk degeneration. Because this is an invasive procedure, less invasive diagnostic tests are usually done first.

Myelography (myelogram) is the injection of a special X-ray dye into a layer of the spinal cord covering to outline its dimension and shape. The picture can be obtained through an X-ray or computed tomography scan. Myelograms are typically reserved for preoperative planning in special situations, such as before surgery for spinal stenosis.


Treatment
Treatment decisions are based on various factors, including:
probable causes of the pain
your age, lifestyle and personal preferences
other medical problems
available support
risks and benefits of treatment
Some treatment options are best for acute back pain and others are best for chronic pain. Since most people with back pain recover on their own within four weeks, treatment usually begins with simple measures such as activity modification and medications to ease pain, reduce inflammation and promote quality sleep.

Staying active
Cautiously continuing light activity can promote healing. If you have acute pain, maintain your regular schedule as much as possible, including going to work. Avoid high-risk activities such as heavy lifting, twisting, bending forward, reaching, sitting or standing for long periods of time, and straining with a bowel movement.

Resist the temptation to lie in bed for more than a day or two. Prolonged bedrest can lead to other problems, such as stiff joints, muscle wasting and deconditioning, and bone mineral loss.

Medications
Various medications may be used to treat back pain. For example:

Nonsteroidal anti-inflammatory medications (NSAIDs): Your doctor may recommend over-the-counter NSAIDs such as aspirin, ibuprofen or naproxen to alleviate acute back pain. He or she may also prescribe stronger NSAIDs. These medications may or may not help, depending on the source of the pain. They may also cause stomach irritation.

Narcotic medications: Narcotic medications play a limited role in the treatment of low back pain. They may be used for the initial treatment of severe pain, but usually not longer than two weeks because they can be addictive. They can also cause side effects, such as drowsiness and constipation.

Antidepressants: Low-dose antidepressants are sometimes prescribed to treat chronic pain conditions. Research doesn't support the use of antidepressants for acute low back pain.

Muscle relaxants: Muscle relaxants may be effective for treating some types of back pain, but their benefit for treating chronic back pain or herniated disks hasn't been proven. In fact, they may not be any more effective than NSAIDs and they have more serious side effects, such as dependency, drowsiness and dizziness. Muscle relaxants are usually prescribed only for a short time, typically in combination with NSAIDS.

Steroid medications: Oral steroids can reduce inflammation and relieve pain, but they're not the first course of treatment for most cases of acute back pain. NSAIDs may need to be avoided or minimized when oral steroids are taken.

Benefits: Medications are generally a safe, noninvasive first line of treatment for common back pain conditions. Most NSAIDs have fewer side effects than narcotics, muscle relaxants and steroids. NSAIDS also cost less and are safe and effective for most people.

Risks: Side effects of over-the-counter or prescription medications may include drowsiness, stomach irritation, bleeding, nausea, rash or dizziness. If you develop any side effects, stop taking the medication and consult your doctor. Side effects may occur more often after age 60 and in people who take multiple medications. If you're pregnant or breastfeeding, discuss any medication use with your doctor.
Heat or cold applied to the back
Applying heat or cold to the affected area may relieve pain temporarily. For low back pain caused by overuse, trauma, possible repetitive injury, muscle strain or undiagnosed pain, apply an ice pack during the first 24 hours for 10 to 15 minutes at a time, three to four times a day. Once the swelling has subsided, apply warm, moist heat to the area 10 to 15 minutes at a time, three to four times a day.

Newer heat application products (ThermaCare, for example) can be worn for up to eight hours. For deeper heating, your doctor may recommend ultrasound therapy (the use of sound waves to heat tissues).

Benefits: Hot and cold packs are easy to apply, inexpensive and safe when used as directed.

Risks: Burns are possible if heat or cold is applied too long or without a protective cover (such as a towel) between the thermal source and the skin. Injury is a greater risk for people who have impaired sensation or nerve disease.
Back exercises and back schools
A structured exercise program can help people who have chronic back pain. For acute back pain, exercise doesn't seem to be any better than other treatments. It's important to follow any recommendations from your doctor or physical therapist. Some exercises can do more harm than good.

Back schools taught by doctors or physical therapists are available in some workplace settings. They're designed to educate employees about how the back works, what can go wrong, and how to minimize back injury. They may also include tips on exercise.

Benefits: Exercise and education can help reduce chronic back pain. People who remain active tend to have less pain and depression, as well as an improved sense of health and well-being.

Risks: Injury is possible. Be careful to follow instructions from your doctor or physical therapist.
Multidisciplinary treatment programs
Intensive treatment programs that involve professionals from many disciplines, such as a doctor, physical therapist, psychologist, social worker and occupational therapist, can be helpful for people who have chronic back pain. Programs that offer some sort of treatment every day seem to be most effective.

Benefits: This type of program seems to be most helpful for people who have chronic back pain.

Risks: Results may depend on daily participation.
Behavior therapy
Behavior therapy is based on the theory that how you feel about your pain can make it better or worse. Through weekly sessions with a therapist, you can learn stress management and relaxation skills.

Benefits: Behavior therapy seems to be most effective for people who have chronic pain.

Risks: Results may depend on your commitment to therapy, as well as the therapist's skill.
Spinal manipulation
Spinal manipulation involves adjusting the joints of the spine by pressing on the back bone or manipulating limbs to realign any misplaced segments. The best known technique, called high velocity thrust, often produces the sound of a joint cracking. Spinal manipulation should be done by experienced professionals, such as chiropractors or osteopaths. It hasn't yet been established how many manipulations are needed, who are the best candidates or which specific techniques are best.

Benefits: People who have acute and chronic back pain or herniated lumbar disks may enjoy some degree of symptom relief.

Risks: Few complications from appropriate treatment have been reported. There's a risk of injury for people who have rheumatoid arthritis, spinal stenosis, severe spinal arthritis, sciatica or osteoporosis. Spinal manipulation isn't recommended for people who have damaged spinal nerves. Spinal manipulation may be expensive, depending on how many treatments are needed. Some people may begin to rely on spinal manipulations and reduce self-care efforts that may improve their health and help prevent another injury. Others may delay seeking necessary medical attention by relying solely on these treatments.
Acupuncture
One of the major clinical uses for acupuncture is pain control. It's done by placing thin needles into the skin at specific points in the body according to principles of Chinese medicine.

Benefits: Acupuncture is thought to stimulate the release of natural chemicals that block pain sensations in the brain and spinal cord. Several studies on chronic back pain have shown acupuncture may be helpful. No studies have been done to evaluate acupuncture for acute back pain.

Risks: For most health professionals, the biggest concern is that people may delay seeking necessary medical attention by relying solely on acupuncture treatments. Possible complications include tissue injury and infection.
If you're considering acupuncture, interview potential practitioners. Ask about qualifications and safety practices. Only consent to treatment from a practitioner who uses sterile, disposable needles.

Epidural steroid injections
An epidural steroid injection may help relieve pain by reducing swelling and inflammation. During the procedure, which is typically done by an anesthesiologist or radiologist, a needle is guided into the lower back to the epidural space (the space surrounding the spinal cord). A steroid solution is then injected into the epidural space. Epidurals may be more appropriate for chronic back pain and those who hope to delay or avoid surgery.

Benefits: Epidural steroid injections are thought to numb the nerve roots and reduce inflammation. Reduced pain allows people to return to more active lifestyles and may improve sleep quality.

Risks: Epidural injections are expensive, and they may not adequately relieve the pain. The most common complications are pain at the injection site and a headache. Serious, but rare, complications may include infection, meningitis (inflammation of the membranes surrounding the brain and spinal cord) and neurological problems.
Injections into trigger points or ligaments
Injections of a steroid and local anesthetic into trigger points (areas on the back that trigger pain when touched) or ligaments (the bands of tissue that hold the vertebrae together) may ease chronic back pain.

Benefits: The injections seem to have a long-term numbing effect. It's not completely understood why injecting a short-acting medication can produce a long-term effect.

Risks: There's a potential for damage to nerves or other tissue, as well as infections or bleeding.
Surgery
When surgery is recommended, the type of surgery is based on the underlying cause of the back pain. Some of the more common types of surgery include:

Laminectomy: With this procedure, the doctor removes a small portion of the vertebral bone over the spine, freeing up any pressure over a nerve root. This is especially helpful for people who have spinal stenosis.

Discectomy: With this procedure, the doctor removes the herniated disk that's pressing on the nerve root. Often, just the portion of disk pressing on the nerve is removed. This is known as a microdiscectomy.

Spinal fusion: With this procedure, bone grafts, metal plates, screws or other appliances are used to join one or more vertebrae together to stabilize the spine where a disk is deteriorated or was removed.

If you're considering surgery, talk to your surgeon about the risks, benefits, recovery and postoperative therapy. In the case of any rapidly increasing neurological deficits, emergency surgery may be needed.

Benefits: Surgery may speed recovery of low back pain for some people. Stabilization of the spine may minimize the potential for further complications, such as spinal cord injury.

Risks: An initial surgery may increase the likelihood for future surgeries. In turn, repeat surgeries have the potential for higher complication rates. Infection or bleeding occurs in a small percentage of first-time surgeries. The long-term results of some types of back surgery may be comparable to the long-term results of nonsurgical treatment.
Treatment options that lack conclusive support from research studies

transcutaneous electrical nerve stimulation (TENS)
traction
corsets, braces and back belts
massage
facet joint injections
electromyographic (EMG) biofeedback
physical conditioning programs

Considerations
If your condition doesn't improve or gets worse, consult your doctor for another evaluation and follow-up care. If the pain doesn't improve after two to four weeks of treatment, your doctor may order additional tests or treatment.

Pregnancy-specific information
As your baby grows, your center of gravity will change and your body may be thrown off balance. You'll probably change the way you walk, stand and sit. This may contribute to back problems.
It's important to practice good body mechanics. Discuss any back or leg pain with your doctor. Remember that sudden back pain during pregnancy can be a sign of labor.

X-rays, certain medications and surgery are usually avoided during pregnancy. Talk to your doctor before taking any medications or trying other treatments for back pain.


Senior-specific information
The degenerative effects of aging on the back, combined with injuries that may occur over time, increase the risk of low back pain for older adults. Treatment options are the same for older adults, but healing may occur more slowly. Treatment choices will be influenced by your medical history and overall health.

Prevention
To prevent low back pain:
Concentrate on good posture and proper body mechanics. Avoid frequent bending and twisting at the waist, and try not to lift heavy objects. If you must lift something heavy, use your legs, keep your back straight, and hold the item as close to your body as possible.

Avoid sitting or standing for long periods of time.

Adjust your workstation to a comfortable height, and sit in a chair with good back support. If you must sit for long periods of time, rest your feet on a stool. Take frequent breaks and short walks.

When driving a car, use supportive seats.

Sleep on a firm mattress. Place a pillow between your legs when lying on your side, and use a pillow under your knees when lying on your back.

Maintain a healthy weight.

Exercise regularly. Always consult your doctor before beginning an exercise program.

If you smoke, quit.

Wear comfortable, low-heeled shoes.

Avoid constipation or straining during bowel movements.

Minimize stress as much as possible.