 |
 |
Keywords
Bulging/Protruded/Herniated/Ruptured Lumbar Disc «» Degenerative Disc Disease «» Fibromyalgia «» Kyphosis «» Lordosis «» Lumbar/Spinal Stenosis «» Pinched Nerve «» Radiculopathy/Radicular Pain «» Sciatica «» Scoliosis «» Spondylitis
What is the anatomy of the spine?
What is back pain?
What causes back pain?
Who is at risk?
What conditions are associated with back pain?
How is back pain diagnosed?
How is back pain treated?
How can back pain be prevented?
What is the anatomy of the spine?
The spine is an intricate structure, made up of bones, muscles, and other tissues, which not only supports the upper body’s weight but also houses and protects the spinal cord -- the delicate nervous system structure that carries signals that control the body’s movements and convey its sensations. Stacked on top of one another are more than 30 bones (vertebrae) that form the spinal column. Each of these bones contains a round hole that, when stacked in register with all the others, creates a channel that surrounds the spinal cord. The spinal cord descends from the base of the brain and extends in the adult to just below the rib cage.
Small nerves enter and emerge from the spinal cord through spaces between the vertebrae. Because the bones of the spinal column continue growing long after the spinal cord reaches its full length in early childhood, the nerve roots to the lower back and legs extend many inches down the spinal column before exiting. This large bundle of nerve roots was dubbed by early anatomists as the cauda equina, or horse’s tail. The spaces between the vertebrae are maintained by round, spongy pads of cartilage called intervertebral discs that allow for flexibility in the lower back and act much like shock absorbers throughout the spinal column to cushion the bones as the body moves. Bands of tissue known as ligaments and tendons hold the vertebrae in place and attach the muscles to the spinal column.
Starting at the top, the spine has four regions: the seven cervical or neck vertebrae (labeled C1–C7), the 12 thoracic or upper back vertebrae (labeled T1–T12), the five low back or lumbar vertebrae (labeled L1–L5), and the sacrum and coccyx, a group of bones fused together at the base of the spine. The lumbar region of the back, where most back pain is felt, supports the weight of the upper body.
Simply stated, back pain is any type of pain or discomfort that is experienced in the mid to lower back -- usually caused by chronic wear and tear, trauma, or strain on the components that make up the spine. Nearly every person, at some point in their life, has back pain that interferes with work, routine daily activities, or recreation. Americans spend at least $50 billion each year on low back pain, the most common cause of job-related disability and a leading contributor to missed work. Back pain is the second most common neurological ailment in the United States -- only headache is more common.
Acute, or short-term, low back pain generally lasts from a few days to a few weeks. Most acute back pain is mechanical in nature -- the result of trauma to the lower back or a disorder such as arthritis. Pain from trauma may be caused by a sports injury, work around the house or in the garden, or a sudden jolt such as a car accident or other stress on spinal bones and tissues. Symptoms may range from muscle ache to shooting or stabbing pain, limited flexibility and/or range of motion, or an inability to stand straight. Some acute pain syndromes can become more serious if left untreated.
Chronic back pain is measured by duration -- pain that persists for more than 3 months is considered chronic. It is often progressive and the cause can be difficult to determine.
As people age, bone strength and muscle elasticity and tone tend to decrease; and the discs begin to lose fluid and flexibility, which decreases their ability to cushion the vertebrae. Pain can occur with over-exertion, causing a sprain, strain, or spasm in one of the muscles or ligaments in the back, or rupture of a disc. This rupture may put pressure on one of the more than 50 nerves that emerge from or enter the spinal cord. When these nerve roots become compressed or irritated, back pain results.
Low back pain may reflect nerve or muscle irritation or bone lesions. Most low back pain follows injury or trauma to the back, but pain may also be caused by degenerative conditions such as arthritis or disc disease, osteoporosis or other bone diseases, viral infections, irritation to joints and discs, or congenital abnormalities in the spine. Obesity, smoking, weight gain during pregnancy, stress, poor physical condition, posture inappropriate for the activity being performed, and poor sleeping position also may contribute to low back pain. Additionally, scar tissue created when the injured back heals itself does not have the strength or flexibility of normal tissue. Buildup of scar tissue from repeated injuries eventually weakens the back and can lead to more serious injury.
Occasionally, low back pain may indicate a more serious medical problem. Pain accompanied by fever or loss of bowel or bladder control, pain when coughing, and progressive weakness in the legs may indicate an infection, spine tumor, pinched nerve or other serious conditions. People with diabetes can have chronic nerve damage which may manifest itself as severe back pain or pain radiating down the leg. These are issues that require more immediate attention by a physician.
Nearly everyone has low back pain at some point in their lifetime. It occurs most often between ages 30 and 50, due in part to the aging process and more sedentary life styles; and it affects men and women equally. The risk of experiencing low back pain from disc disease or spinal degeneration increases with age.
Low back pain unrelated to injury or other known causes is unusual in pre-teen children. However, a backpack overloaded with schoolbooks and supplies can quickly strain the back and cause muscle fatigue. The U.S. Consumer Product Safety Commission estimates that more than 13,000 injuries related to backpacks are treated by health care professionals each year. To avoid back strain, children carrying backpacks should bend both knees when lifting heavy packs, visit their locker or desk between classes to lighten loads or replace books, or purchase a backpack or airline tote on wheels.
What conditions are associated with back pain?
Conditions that may cause low back pain and require treatment by a physician or other health specialist include:
Bulging, Protruded, Herniated, or Ruptured Disc (also known as Degenerative Disc Disease): The intervertebral discs are under constant pressure. As discs degenerate and weaken over time, cartilage can bulge or be pushed into the space containing the spinal cord or a nerve root, causing pain -- a phenomenon commonly known as a pinched nerve, radicular pain, radiculopathy, or sciatica. Studies have shown that most herniated discs occur in the lower lumbar portion of the spinal column. A much more serious complication of a ruptured disc is cauda equina syndrome, which occurs when disc material is pushed into the spinal canal and compresses a bundle of lumbar and sacral nerve tissue which can lead to weakness of the legs, numbness in the groin region, and/or bowel or bladder incontinence. Permanent neurological damage may result if this syndrome is left untreated for more than a few hours. Sciatica is a condition in which a herniated or ruptured disc compressing the sciatic nerve, which is a large nerve that that carries nerve fibers to the leg. This compression causes shock-like or burning low back pain combined with pain through the buttocks and down one or both legs to below the knee, occasionally reaching the foot. In the most extreme cases, when the nerve is pinched between the disc and an adjacent bone, the symptoms involve not pain but numbness and some loss of motor control over the leg due to interruption of nerve signaling. The condition may also be caused by a tumor, cyst, or degeneration of the sciatic nerve root.
Spinal Stenosis: Spinal degeneration from disc wear and tear can lead to a narrowing of the spinal canal, called stenosis. A person with this disorder may experience stiffness in the back upon awakening or may feel pain after walking or standing for a long time. Spinal stenosis related to congenital narrowing of the bony canal predisposes some people to pain related to disc disease.
Osteoporosis: This is a metabolic bone disease marked by progressive decrease in bone density and strength. Fracture of brittle, porous bones in the spine (Vertebral Compression Fractures) and hips results when the body fails to produce new bone and/or absorbs too much existing bone. Women are four times more likely than men to develop osteoporosis, and caucasian women of northern European heritage are at the highest risk.
Abnormal Spinal Curvature: Skeletal irregularities produce strain on the vertebrae and supporting muscles, tendons, ligaments, and other tissues. These irregularities can lead to scoliosis (a curving of the spine to one side), kyphosis (increase in the normal curve of the upper back), or lordosis (an abnormally accentuated arch in the lower back).
Fibromyalgia: This is a chronic disorder characterized by widespread musculoskeletal pain, fatigue, and multiple tender points, particularly in the neck, spine, shoulders, and hips. Additional symptoms may include sleep disturbances, morning stiffness, and anxiety.
Spondylitis: This refers to chronic back pain and stiffness caused by a severe infection or inflammation of the spinal joints. Other painful inflammations in the lower back include osteomyelitis (infection in the bones of the spine) and sacroiliitis (inflammation in the sacroiliac joints).
How is low back pain diagnosed?
A thorough medical history and physical exam can usually identify any dangerous conditions or family history that may be associated with back pain. The physician will examine the back and conduct neurologic tests to determine the cause of pain and appropriate treatment. Blood tests may also be ordered, and imaging tests may be necessary to diagnose tumors or other possible sources of the pain. A variety of diagnostic methods are available to confirm the cause of low back pain, including x-rays, computed tomography (CT), magnetic resonance imaging (MRI), discography, myelography, and electrodiagnostic procedures.
X-ray: This imaging modality includes conventional and enhanced methods that can help diagnose the cause and site of back pain. A conventional x-ray, often the first imaging technique used, looks for broken bones or injured vertebrae. Tissue masses such as injured muscles and ligaments or painful conditions such as a bulging disc are not visible on conventional x-rays. This fast, noninvasive, and painless procedure is usually performed in a doctor’s office or at a clinic.
Computed Tomography (CT): This is a quick and painless exam that is used when damage or trauma to the bony vertebrae is suspected as a cause of back pain. x-rays are passed through the body at various angles and are detected by a computerized scanner to produce two-dimensional images of internal structures of the back. This diagnostic exam is generally conducted at an imaging center or hospital.
Magnetic Resonance Imaging (MRI): This imaging modality is used to evaluate the lumbar region for bone degeneration, injury or disease in tissues and nerves, muscles, ligaments, and blood vessels, or to detect herniated discs. MRI scanning equipment uses a strong magnetic field (not x-rays) and radio waves to generate signals from tissue that are then interpreted by a computer which creates pictures of the tissue being scanned, and differentiates between bone, soft tissues and fluid-filled spaces by their structural properties. This noninvasive procedure is often used to identify a condition requiring prompt surgical treatment.
Discography: This technique involves the injection of a special contrast dye into a spinal disc thought to be causing low back pain. The dye outlines the damaged areas on x-rays taken following the injection and can provide information with regard to the integrity of the disc. Furthermore, the injection of the dye into the disc will usually reproduce the patient's pain; and, when compared to discography results for normal discs (which should be pain-free), can more definitively rule in the diseased disc as the source of the pain. This procedure is often suggested for patients who are considering lumbar surgery or whose pain has not responded to conventional treatments.
Myelography: In this procedure, the contrast dye is injected into the spinal canal, followed by a CT or x-ray imaging of the spine. This allows for detection of spinal cord and nerve compression caused by herniated discs or masses within the spinal canal.
Electrodiagnostic Procedures: These include electromyography (EMG), nerve conduction studies (NCS), and evoked potential (EP) studies. EMG assesses the electrical activity in a nerve and can detect if muscle weakness results from injury or a problem with the nerves that control the muscles. Very fine needles are inserted in muscles to measure electrical activity transmitted from the brain or spinal cord to a particular area of the body.
With nerve conduction studies the physician uses two sets of electrodes that are placed on the skin over the muscles. The first set gives the patient a mild shock to stimulate the nerve that runs to a particular muscle, and the second set of electrodes is used to make a recording of the nerve’s electrical signals in response to the shock. From this information the doctor can determine if there is nerve damage.
EP tests also involve two sets of electrodes -- one set to stimulate a sensory nerve and the other set on the scalp to record the speed of nerve signal transmissions to the brain. Changes in the speed of transmission of the signal to the brain can help to diagnose certain nerve or spinal cord diseases.
Most low back pain can be treated without surgery. Treatment involves using analgesics, reducing inflammation, restoring proper function and strength to the back, and preventing recurrence of the injury. Most patients with back pain recover without residual functional loss, but patients should contact a doctor if there is not a noticeable reduction in pain and inflammation after 72 hours of self-care, or immediately if there is any numbness, weakness, bowel or bladder problems, or any other neurologic deficits.
Although the use of cold and hot compresses have never been scientifically proven to quickly resolve low back injury, compresses may help reduce pain and inflammation and allow greater mobility for some individuals. As soon as possible following trauma, patients should apply a cold compress (such as a bag of ice or bag of frozen vegetables wrapped in a towel) to the tender spot several times a day for up to 20 minutes. After 2 to 3 days of cold treatment, they should then apply heat (such as a heating pad) for brief periods to relax muscles and increase blood flow -- warm baths may also help relax muscles. Patients should avoid sleeping on a heating pad, which can cause burns and lead to additional tissue damage.
Bed rest is only recommended for a maximum of 1 to 2 days. Studies have shown that persons who continued their activities without bed rest following onset of low back pain appeared to have better back flexibility than those who rested in bed for a week. Other studies suggest that bed rest alone may make back pain worse and can lead to secondary complications such as depression, decreased muscle tone, and life-threatening blood clots in the legs. Therefore, patients should resume activities as soon as possible.
Exercise may be the most effective way to speed recovery from low back pain and help strengthen back and abdominal muscles. Maintaining and building muscle strength is particularly important for persons with skeletal irregularities. Doctors and physical therapists can provide a list of gentle exercises that help keep muscles moving and speed the recovery process. A routine of back-healthy activities may include stretching exercises, swimming, walking, and movement therapy to improve coordination and develop proper posture and muscle balance. Yoga and Pilates are other ways to gently stretch and strengthen muscles and ease pain. Any mild discomfort felt at the start of these exercises should disappear as muscles become stronger. But if pain is more than mild and lasts more than 15 minutes during exercise, patients should stop exercising and contact a doctor.
Medications are often used to treat acute and chronic low back pain. Effective pain relief may involve a combination of prescription drugs and over-the-counter remedies. Patients should always check with a doctor before taking drugs for pain relief since certain medicines, even those sold over the counter, are unsafe during pregnancy, may conflict with other medications, may cause side effects including drowsiness, or may lead to liver damage. Over-the-counter analgesics, including nonsteroidal anti-inflammatory drugs (aspirin, naproxen, and ibuprofen), are taken orally to reduce stiffness, swelling, and inflammation and to ease mild to moderate low back pain. Counter-irritants applied topically to the skin as a cream or spray stimulate the nerve endings in the skin to provide feelings of warmth or cold and dull the sense of pain. Topical analgesics can also reduce inflammation and stimulate blood flow. Many of these compounds contain salicylates, the same ingredient found in oral pain medications containing aspirin.
Opioids, such as codeine, oxycodone, hydrocodone, and morphine, are often prescribed to manage severe acute and chronic back pain but should be used only for a short period of time and under a physician’s supervision. Side effects can include drowsiness, decreased reaction time, impaired judgment, and potential for addiction. Many specialists are convinced that chronic use of these drugs is detrimental to the back pain patient, adding to depression and even increasing pain.
Interventional therapy can ease chronic pain by blocking nerve conduction between specific areas of the body and the brain. Approaches range from injections of local anesthetics, steroids, or narcotics into affected soft tissues, joints, or nerve roots to more complex nerve blocks and spinal cord stimulation. When extreme pain is involved, low doses of drugs may be administered by catheter directly into the spinal cord. Chronic use of steroid injections may lead to increased functional impairment.
Anticonvulsants (drugs primarily used to treat seizures) may also be useful in treating certain types of nerve pain and may also be prescribed with analgesics. In addition, some antidepressants, particularly tricyclic antidepressants (amitriptyline and desipramine) have been shown to relieve pain and assist with sleep.
Antidepressants alter levels of brain chemicals to elevate mood and dull pain signals. Many of the new antidepressants, such as the selective serotonin reuptake inhibitors, are being studied for their effectiveness in pain relief.
Acupuncture has also been shown to relieve back pain, and it involves the insertion of needles the width of a human hair along precise points throughout the body. Practitioners believe this process triggers the release of naturally occurring painkilling molecules which help to relieve the symptoms of back pain.
Biofeedback is used to treat many acute pain problems, most notably back pain and headache. Using a special electronic machine, the patient is trained to become aware of, to follow, and to gain control over certain bodily functions, including muscle tension, heart rate, and skin temperature by controlling local blood flow patterns. The patient can then learn to change his or her response to pain, for example, by using relaxation techniques. Biofeedback is often used in combination with other treatment methods, generally without side effects.
Traction involves the use of weights to apply constant or intermittent force to gradually pull the skeletal structures into better alignment. Traction is not recommended for treating acute low back symptoms or pain due to spine fractures.
Transcutaneous electrical nerve stimulation (TENS) is administered by a battery-powered device that sends mild electric pulses along nerve fibers to block pain signals to the brain. Small electrodes placed on the skin at or near the site of pain generate nerve impulses that block incoming pain signals from the peripheral nerves. TENS may also help stimulate the brain’s production of endorphins, which are chemicals that have pain-relieving properties.
Ultrasound is a noninvasive therapy that sends sound waves (undetectable by human ears) into the injured muscles and other soft tissues and warms the body’s internal tissues, which causes muscles to relax.
In the most serious cases, when the condition does not respond to other therapies, surgery may relieve pain caused by back problems or serious musculoskeletal injuries. It may be months following surgery before the patient is fully healed, and he or she may suffer permanent loss of flexibility, depending on the type of surgery. Since invasive back surgery is not always successful, it should be performed only in patients with progressive neurologic disease or damage to the peripheral nerves. Some of the surgical procedures commonly performed to relieve back pain are listed below.
Discectomy is one of the more common ways to remove pressure on a nerve root from a bulging disc or bone spur. During the procedure the surgeon takes out a small piece of the lamina (the arched bony roof of the spinal canal) in order to gain access to the herniated disc or bone spur which can be removed to relieve nerve compression.
Foraminotomy is an operation that enlarges the bony hole (foramen) through which a nerve root exits the spinal canal. Bulging discs or joints thickened with age can cause narrowing of the space through which the spinal nerve exits and can press on the nerve, resulting in pain, numbness, and weakness in an arm or leg. Small pieces of bone over the nerve are removed through a small incision, allowing relief of pressure on the nerve.
Spinal laminectomy (also known as spinal decompression) involves the removal of the lamina (usually both sides) to increase the size of the spinal canal and relieve pressure on the spinal cord and nerve roots.
Spinal fusion is used to strengthen the spine and prevent painful movements. The spinal disc between two vertebrae is removed and the adjacent vertebrae are “fused” by bone grafts and/or metal devices secured by screws. Spinal fusion may result in some loss of flexibility in the spine and requires a long recovery period to allow the bone grafts to grow and fuse the vertebrae together.
Minimally invasive outpatient treatments to seal fractures of the vertebrae caused by osteoporosis include vertebroplasty and kyphoplasty. Vertebroplasty uses three-dimensional imaging to help a doctor guide a needle into the vertebral body. A glue-like substance is injected into the damaged vertebral body, which quickly hardens to stabilize and strengthen the bone and provide immediate pain relief. In kyphoplasty, prior to injecting the glue-like substance, a special balloon is inserted and gently inflated to restore height to the bone and reduce spinal deformity.
IntraDiscal Electrothermal Therapy (IDET) uses thermal energy to treat pain resulting from a cracked or bulging spinal disc. A special needle is inserted into the disc and heated to a high temperature for up to 20 minutes. The heat thickens and seals the disc wall and reduces inner disc bulge and irritation of the spinal nerve.
Nucleoplasty uses radiofrequency energy to treat patients with low back pain from contained, or mildly herniated, discs. Guided by x-ray imaging, a wand-like instrument is inserted through a needle into the disc to create a channel that allows inner disc material to be removed. The wand then heats and shrinks the tissue, sealing the disc wall. Several channels are made depending on how much disc material needs to be removed.
Radiofrequency lesioning is a procedure using electrical impulses to interrupt nerve conduction (including the conduction of pain signals) for 6 to12 months. Using x-ray guidance, a special needle is inserted into nerve tissue in the affected area. Tissue surrounding the needle tip is heated for 90-120 seconds, resulting in localized destruction of the nerves.
Other surgical procedures to relieve severe chronic pain include rhizotomy, in which the nerve root is cut to block nerve transmission and all senses from the area of the body experiencing pain; cordotomy, where bundles of nerve fibers on one or both sides of the spinal cord are intentionally severed to stop the transmission of pain signals to the brain; and dorsal root entry zone (DREZ) operation, in which spinal neurons transmitting the patient’s pain are destroyed surgically.
How can back pain be prevented?
Recurring back pain resulting from improper body mechanics or other non-traumatic causes is often preventable. A combination of proper exercises, maintaining correct posture, and lifting objects properly can help prevent injuries.
Many work-related injuries are caused or aggravated by stressors such as heavy lifting, vibration, repetitive motion, awkward posture, and contact stress -- repeated or constant contact between soft body tissue and a hard object, such as resting a wrist against the edge of a hard desk or repeated tasks using a hammering motion. Applying ergonomic principles -- designing furniture and tools to protect the body from injury -- at home and in the workplace can greatly reduce the risk of back injury and help maintain a healthy back. More companies and homebuilders are promoting ergonomically designed tools, products, workstations, and living space to reduce the risk of musculoskeletal injury and pain.
Following any period of prolonged inactivity, a program of regular low-impact exercise, such as speed walking, swimming, or stationary bike riding for 30 minutes a day, is recommended to increase muscle strength and flexibility. Yoga and Pilates can also help to stretch and strengthen muscles and improve posture.
It is also important to always stretch before exercise or other strenuous physical activity, and to not slouch when standing or sitting since the spine supports weight most easily when curvature is reduced.
Factors that contribute to a healthy back include a chair with good lumbar support, proper position and height of the desk, keeping the shoulders back when sitting, switching sitting positions often, periodically walking around the office or gently stretch muscles to relieve tension, resting both feet on a low stool, wearing comfortable and low-heeled shoes, sleeping on one side to reduce any curve in the spine, using a firm mattress for sleep, avoiding lifting heavy objects without proper help, lifting with the knees instead of bending over at the waist to lift, maintaining proper nutrition and diet to reduce and prevent excessive weight, quitting smoking, and daily intake of sufficient amount of calcium, phosphorus, and vitamin D.
