Low Back Pain

views updated Jun 11 2018

Low back pain

Definition

Low back pain (LBP) is a common complaintsecond only to cold and flu as a reason why patients seek care from their family doctor. It may be a limited musculoskeletal symptom or caused by a variety of diseases and disorders that affect or extend from the lumbar spine. Low back pain is sometimes accompanied by sciatica, which is pain that involves the sciatic nerve and is felt in the lower back, the buttocks, the backs and sides of the thighs, and possibly the calves. More serious causes of LBP may be accompanied by fever , night pain that awakens a person from sleep, loss of bladder or bowel control, numbness, burning urination, swelling or sharp pain.

Description

Low back pain is a symptom that affects 80% of the general United States population at some point in life with sufficient severity to cause absence from work. As mentioned, it is the second most common reason for visits to primary care doctors, and is estimated to cost the American economy $75 billion every year. One third of the nation's disability related costs are associated with LBP, a condition primarily affecting individuals between the ages of 4560.

The most common cause of low back pain is lumbar strain. The structures of the normal lumbar region of the spine include the lumbar vertebrae, discs between each vertebrae, ligaments, muscles and muscle tendons, the

spinal cord within the vertebrae and nerves extending out-ward from the spine through vertebral foramina (openings in the bone). The lumbar vertebrae are distinct from the cervical (neck area) and thoracic (upper back) vertebrae, being generally thicker for greater weight bearing support, and resting atop the sacrum, the triangular shaped bone between the buttocks. The discs between each vertebrae of the spine cushion and absorb the shock that might otherwise be transmitted through the spine. Occasionally, the discs may "rupture" or herniate outward through their fibrous sheath, or covering, putting pressure on the nerves. Nerve pressure as sciatica (affecting the sciatic nerve) may be causative or additive to LBP. Nerve pain from other local organs may also be causative, in which case diagnosis and treatment is more involved, usually much more serious, and may indicate a life threatening condition.

Risks for low back pain are increased with fracture and osteoporosis , narrowing of the spinal canal within the vertebrae (stenosis), spinal curvatures, fibromyalgia , osteo- and rheumatoid arthritis, pregnancy, smoking, stress , age greater than 30, or disease or illness of the organs of the lower abdomen.

In addition to dividing low back pain into three categories based on duration of symptomsacute, sub-acute or chroniclow back pain may be described as:

  • Localized. In localized pain the patient will feel soreness or discomfort when the doctor palpates, or presses on, a specific surface area of the lower back.
  • Diffuse. Diffuse pain is spread over a larger area and comes from deep tissue layers.
  • Radicular. The pain is caused by irritation of a nerve root and radiates from the area. Sciatica is an example of radicular pain.
  • Referred. The pain is perceived in the lower back, but actually is caused by inflammation or disease elsewhere, such as the kidneys or other structures of or near the lower abdomen including the intestines, appendix, bladder, uterus, ovaries or the testes.

Causes & symptoms

Acute and sub-acute pain

Lumbar strain or sprain is the most common cause of acute low back pain. It is pain that does not usually extend to the leg and usually occurs within 24 hours of heavy lifting or overuse of the back muscles. The pain is usually localized, and may be accompanied by muscle spasms or soreness to touch. The patient usually feels better when resting. Acute strain may follow a sudden movement, especially a lifting and simultaneous twisting motion, however injury is usually preceded by overuse or lack of exercise and tone especially of the opposing muscles (the abdominals, for example), improper use, long periods of sitting or standing in one position, poor vertebral alignments or conditions compromising nutrition of the supportive structures. Acute low back pain due to lumbar strain (approximately 60% of sufferers) usually resolves with a week with conservative therapies, including reducing but not eliminating all activity. Sub-acute pain is associated with a duration of 612 weeks, by which time 90% of persons suffering low back pain and injury return to work. This category accounts for one third of all disability related costs. LBP persisting beyond three months is considered chronic. Symptoms of acute LBP may be accompanied by stiffness (guarding), constipation , poor sleep and trouble finding a comfortable position, difficulties walking and other limits on normal range of motion.

Chronic pain

Chronic low back pain has several different possible causes.

MECHANICAL. Chronic strain on the muscles of the lower back may be caused by obesity , pregnancy, or jobrelated stooping, bending, or other stressful postures. Construction, truck driving accompanied by vibration, jack hammering, sand blasting and other sources of chronic trauma and strain to the back or nerve pressure also contribute.

MALIGNANCY OR OTHER SERIOUS ILLNESS. Low back pain at night that is not relieved by lying down may be caused by a tumor in the cauda equina (the roots of the spinal nerves controlling sensation in and movement of the legs), or metastasized cancer that has spread to the spine from the prostate, breasts, or lungs. The risk factors for the spread of cancer to the lower back include a history of smoking, sudden weight loss, and age over 50. Kidney problems, such as kidney stones ; ovarian and uterine problems, including fibroids, endometriosis , premenstrual water retention, and ovarian cysts ; chronic constipation and sluggish or enlarged colon; benign tumors; bone fractures ; aneurysm of the aorta; herpes zoster shingles ; intra-abdominal infection, or, bleeding secondary to Coumadin therapy; osteomyelitis, tuberculosis of the spine (Pott's disease), and sepsis of the vertebral discsall may be associated with pain to the lower back. Additional symptoms may include night sweats; being awakened at night by pain; weakness, numbness, muscle fatigue or poor coordination which progressively worsens; burning on urination; redness or swelling over the area of pain; changes in bowel or urinary patterns; and malaise.

ANKYLOSING SPONDYLITIS. Ankylosing spondylitis is a form of arthritis that causes chronic pain in the back. The pain is made worse by sitting or lying down, and improves when the patient gets up. It is most commonly seen in males between the ages of 16 and 35. Ankylosing spondylitis is often confused with mechanical back pain in its early stages. Other symptoms include morning stiffness, a positive family history, and positive lab results for HLA-B27 antigen (an autoimmune marker) and an increased sedimentation (Sed) rate of the blood. This condition may have food allergy related components, such as an allergy to wheat, worsened by drinking beer.

HERNIATED SPINAL DISK. Disk herniation is a disorder in which a spinal disk begins to bulge outward between the vertebrae. Herniated or ruptured disks are a common cause of chronic low back pain in adults. Pressure imposed on adjacent nerves results in pain that may worsen on movement, with coughing, sneezing or intraabdominal strain, and be accompanied by numbness of the skin in the area served by the nerve (dermatome). Deep tendon reflexes (DTRs) may be reduced, and the straight leg raising test may be positive. The crossed straight leg raising test, which is more specific to herniated disc, may also be positive.

PSYCHOGENIC. Back pain that is out of proportion to a minor injury, or that is unusually prolonged, may be associated with a somatoform disorder or other emotional disturbance. Psychosocial factors such as loss of work, job dissatisfaction, legal problems, financial compensation issues are some of the 'non-organic' factors that may be associated or causative. Symptoms of low back pain in this configuration are usually diffuse, non-localized, and may include other stress related symptoms. A set of five tests called the Waddell tests may be used to help diagnose LBP of psychogenic origin.

Low back pain with leg involvement

Low back pain that radiates down the leg usually indicates involvement of the sciatic nerve. The nerve can be pinched or irritated by herniated disks, tumors of the cauda equina (the end portion of the spine), abscesses in the space between the spinal cord and its covering, spinal stenosis, and compression fractures. Some patients experience numbness or weakness of the legs, as well as pain. There may be spasming of those muscles otherwise stimulated by the involved nerve, and a positive leg raising test.

Diagnosis

The diagnosis of low back pain can be complicated. Most cases are initially evaluated by primary care physicians or other health practitioners, rather than by specialists.

Initial workup

PATIENT HISTORY. The doctor will ask the patient specific questions about the location of the pain, its characteristics, its onset, and the body positions or activities that make it better or worse. If the doctor suspects that the pain is referred from other organs, he or she may ask about a history of diabetes, peptic ulcers, kidney stones, urinary tract infections , heart murmurs, or other health issues. Age, family history, and previous medical history are also important. LBP in persons younger than 20 and older than 50 are apt to be associated with a more severe underlying condition or cause.

PHYSICAL EXAMINATION. The doctor will examine the patient's back and hips to check for conditions that require surgery or emergency treatment. The examination includes several tests that involve moving the patient's legs in specific positions to test for nerve root irritation or disk herniation. The flexibility of the lumbar vertebrae may be measured to rule out ankylosing spondylitis. Other physical tests include assessments of gait and posture, range of motion, and the ability to perform certain physical positions, coordinated movements. Reflex, sensory and motor tests may help the clinician screen for referral to a specialist, as needed. Diagnostic tests may be used, especially with persisting, chronic pain, for further work up, tests including X-ray, CATscan, MRI, and electromyelographs (EMGs).

RED FLAGS. The presence of certain symptoms warrant a more rapid progress to deeper diagnostic examination as to cause. These serious symptoms include, but are not limited to:

  • pain following violent injury, accident or trauma
  • constant pain that worsens
  • upper spinal pain
  • a history of cancer
  • being HIV positive
  • a history of steroid drug use or drug abuse
  • development of an obvious structural deformity
  • a history of rapid weight loss
  • unexplained fever, or nightsweats, with back pain
  • being younger than 20 and older than 50

Treatment

A thorough differential diagnosis is important before any treatment is considered. There are times when alternative therapies may be most beneficial, and other times when more invasive treatments are needed.

Chiropractic

Chiropractic treats patients by manipulating or adjusting sections of the spine. It is one of the most popular forms of alternative treatment in the United States for relief of back pain caused by straining or lifting injuries, and has been demonstrated through several randomized trials to be beneficial. Some osteopathic physicians, physical therapists, and naturopathic physicians also use spinal manipulation to treat patients with low back pain, along with work on soft tissue around the bones. Additional recommendations of shoe orthotics, exercise, cold packs to reduce and inhibit swelling immediately after injury followed one to two days later by hot packs and cold packs to stimulate healing, hydrotherapy , and life style adjustments may be recommended. Nutritional supplements known to be beneficial to joint repair and integrity, collagen support, and wound repair may also be recommended, including glucosamine sulfate, with or without chondroitin, MSM ,, and a variety of mineral and vitamin cofactors.

Traditional Chinese medicine

Practitioners of traditional Chinese medicine treat low back pain with acupuncture, acupressure , massage, and the application of herbal poultices. They may also use a technique called moxibustion which involves the use of glass cups, and heated air derived use of a burning braid or stick of herb with a distinctive aroma.

Herbal medicine and anti-inflammatory enzymatic therapy

Herbal medicine can utilize a variety of antispasmodic and sedative herbs to help relieve low back pain due to spasm. For this purpose and easily available at a local healthfood store are herbs such as chamomile (Matricaria recutita ), hops (Humulus lupus ), passion flower (Passiflora incarnata ), valerian (Valeriana officinale ), and cramp bark (Viburnum opulus ). Bromelain from pineapples has anti-inflammatory activity. Intake of fresh grape juice, preferably made from from dark grapes, on a daily basis at a time other than mealtime has also been found to be helpful. Minor backaches may be relieved with the application of a heating paste of ginger (Zingiber officinale ) powder and water, allowed to sink in for 10 minutes, and followed by an eucalyptus rub.

Aromatherapy with soothing essential oils of blue chamomile, birch, rosemary , and/or lavender can be effective when rubbed into the affected area after a hot bath.

Homeopathy

Homeopathic treatment for acute back pain consists of various applications of Arnica (Arnica montana ); as an oil or gel applied topically to the sore area or oral doses alone or in prepackaged combination products including other homeopathic such as St. John's wort (Hypericum perforatum ), Rhus tox (Rhus toxicodendron ) and Ruta (Ruta graveolens ). Bellis perennis may be recommended for deep muscle injuries. Other remedies may be recommended based on the symptoms presented by the patient.

Body work and yoga

Massage and the numerous other body work techniques can be very effective in treating low back pain. Yoga , practiced regularly and done properly, can be combined with meditation or imagery to both treat and prevent future episodes of low back pain.

Allopathic treatment

All forms of treatment of low back pain are aimed either at symptom relief or to prevent interference with the processes of healing. None of these methods appear to speed up healing.

Acute pain

Acute back pain is treated with muscle relaxantsor nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or aspirin. Applications of compresses using heat or cold also can be helpful to some patients. Patients are recommended by one source, do not worry, and to stay active. Acute LBP often resolves within a short time. Some patients may be prescribed opiod analgesics (pain relievers with codeine or codeine similars), however, statistics demonstrate no shortening of the healing period, as noted above. The use of muscle relaxants may increase risk of further damage, but they have been shown to be more effective than placebo (though no better than NSAIDS alone) in relieving acute pain. If the patient has not experienced some improvement after several weeks of treatment, the doctor will reinvestigate the cause of the pain.

Chronic pain

Patients with chronic back pain are treated with a combination of medications, physical therapy, and occupational or lifestyle modification. The medications given are usually NSAIDs, although patients with hypertension , kidney problems, or stomach ulcers are advised not take these drugs. Patients who take NSAIDs for longer than six weeks are advised to be monitored periodically for complications. Chronic pain, by definition longer than three months in duration, may also prompt a more thorough diagnostic workup.

Physical therapy for chronic low back pain usually includes regular exercise for fitness and flexibility, and massage or application of heat if necessary. Lifestyle modifications include quitting smoking, weight reduction (if necessary), and evaluation of the patient's occupation or other customary activities. Good lift and bend mechanics may also be reviewed and counseled.

Patients with herniated disks may be treated surgically if the pain does not respond to medication. Vertebral fusion surgery may stiffen the spine, however, engineers of skyscrapers recognize the need of flexibility with height to preserve wind resistance: a fused spine may reduce capacity. A newer surgical procedure known as kyphoplasty, involving guided penetration of the back and cemented repair, may be indicated in pain due to vertebral fracture. Patients with chronic low back pain sometimes benefit from pain management techniques, including biofeedback , acupuncture, and chiropractic manipulation of the spine. Psychotherapy is recommended for patients whose back pain is associated with a somatoform, anxiety , or depressive disorder.

Low back pain with leg involvement

Treatment of sciatica and other disorders that involve the legs may include NSAIDs. Patients with longstanding sciatica or spinal stenosis that do not respond to NSAIDs may be treated surgically. Although some doctors use cortisone injections in trigger points and vertebral facet joints to relieve the pain, this form of treatment is still debated. Also debated are benefits due to spinal traction and transcutaneous (through the skin) electrical nerve stimulation.

Expected results

The prognosis for most patients with acute low back pain is excellent. About 80% of patients recover completely in 46 weeks. The prognosis for recovery from chronic pain depends on the underlying cause.

Prevention

Low back pain due to muscle strain can be prevented by lifestyle choices, including regular physical exercise and weight control, avoiding smoking, and learning the proper techniques for lifting and moving heavy objects. Exercises designed to strengthen the muscles of the lower back and the opposing abdominals are also recommended. Simple actions can also help prevent low back pain, such as putting a small, firm cushion behind the lower back when sitting for long intervals, using a soft pillow for sleep that supports the lower neck without creating an unnatural angle for head and shoulder rest, using a swiveling desk chair with a postural support or stool that maintains the knees at a higher level than the hips, standing on flexible rubber mats to avoid the impact of concrete floors at places of employment for example, and wearing supportive, soft soled shoes, avoiding the use of high heels.

Resources

BOOKS

Esses, Stephen I. "Low Back Pain." In Conn's Current Therapy, edited by Robert E. Rakel. Philadelphia: W. B. Saunders Company, 1998.

Hellman, David B., "Arthritis & Musculoskeletal Disorders." In Current Medical Diagnosis & Treatment 1998, edited by Lawrence. Tierney, Jr., et al. Stamford, CT: Appleton & Lange, 1998.

McKenzie, Robin. Treat Your Own Back. Waikanae, New Zealand: Spinal Publications New Zealand Ltd., 1997.

"Musculoskeletal and Connective Tissue Disorders: Low Back Pain and Sciatica." In The Merck Manual of Diagnosis and Therapy, edited by Robert Berkow, et al. Rahway, NJ: Merck Research Laboratories, 1992.

Theodosakis, Jason, et al. The Arthritis Cure. New York: St. Martin's Paperbacks, 1997.

OTHER

Bratton, M.D., Robert L. Assessment and management of Acute Low Back Pain. Mayo Clinic, Jacksonville, FL. November 15, 1999. [Cited May 28, 2004]. <http://www.aafp.org>.

"Medical Encyclopaedia: Back pain-low." Medline Plus. Updated September 14, 2003, by Jacqueline A. Hart, M.D., Boston. [Cited May 28, 2004]. <http://www.nlm.nih.gov/medlineplus>.

Low Back Pain. Medinfo. Arboris, Ltd. Reviewed October 2, 2002. [Cited May 28, 2004]. <http://www.medinfo.co.uk/conditions/lowbackpain.html>.

Low Back Pain. American Academy of Orthopaedic Surgeons. Reviewd 2000. [Cited May 28, 2004]. <http://www.orthoinfo.aaos.org>.

Shiel Jr., M.D., FACP, FACR, William C. Lower Back Pain (Lumbar Back Pain). MedicineNet. Reviewed April 16, 2004. [Cited May 28, 2004]. <http://www.medicinenet.com>.

Kathleen Wright

Katherine Nelson, N.D.

Low Back Pain

views updated May 14 2018

Low Back Pain

Definition

Low back pain is a common musculoskeletal symptom that may be either acute or chronic. It may be caused by a variety of diseases and disorders that affect the lumbar spine. Low back pain is often accompanied by sciatica, which is pain that involves the sciatic nerve and is felt in the lower back, the buttocks, and the backs of the thighs.

Description

Low back pain is a symptom that affects 80% of the general United States population at some point in life with sufficient severity to cause absence from work. It is the second most common reason for visits to primary care doctors, and is estimated to cost the American economy $75 billion every year.

Low back pain may be experienced in several different ways:

  • Localized. In localized pain the patient will feel soreness or discomfort when the doctor palpates, or presses on, a specific surface area of the lower back.
  • Diffuse. Diffuse pain is spread over a larger area and comes from deep tissue layers.
  • Radicular. The pain is caused by irritation of a nerve root. Sciatica is an example of radicular pain.
  • Referred. The pain is perceived in the lower back but is caused by inflammation elsewhereoften in the kidneys or lower abdomen.

Causes and Symptoms

Acute pain

Acute pain in the lower back that does not extend to the leg is most commonly caused by a sprain or muscle tear, usually occurring within 24 hours of heavy lifting or overuse of the back muscles. The pain is usually localized, and there may be muscle spasms or soreness when the doctor touches the area. The patient usually feels better when resting.

Chronic pain

Chronic low back pain has several different possible causes:

MECHANICAL. Chronic strain on the muscles of the lower back may be caused by obesity; pregnancy; or job-related stooping, bending, or other stressful postures.

MALIGNANCY. Low back pain at night that is not relieved by lying down may be caused by a tumor in the cauda equina (the roots of the spinal nerves controlling sensation in and movement of the legs), or a cancer that has spread to the spine from the prostate, breasts, or lungs. The risk factors for the spread of cancer to the lower back include a history of smoking, sudden weight loss, and age over 50.

ANKYLOSING SPONDYLITIS. Ankylosing spondylitis is a form of arthritis that causes chronic pain in the lower back. The pain is made worse by sitting or lying down and improves when the patient gets up. It is most commonly seen in males between 16 and 35. Ankylosing spondylitis is often confused with mechanical back pain in its early stages.

HERNIATED SPINAL DISK. Disk herniation is a disorder in which a spinal disk begins to bulge outward between the vertebrae. Herniated or ruptured disks are a common cause of chronic low back pain in adults.

PSYCHOGENIC. Back pain that is out of proportion to a minor injury, or that is unusually prolonged, may be associated with a somatoform disorder or other psychiatric disturbance.

Low back pain with leg involvement

Low back pain that radiates down the leg usually indicates involvement of the sciatic nerve. The nerve can be pinched or irritated by herniated disks, tumors of the cauda equina, abscesses in the space between the spinal cord and its covering, spinal stenosis, and compression fractures. Some patients experience numbness or weakness of the legs as well as pain.

Diagnosis

The diagnosis of low back pain can be complicated. Most cases are initially evaluated by primary care physicians rather than by specialists.

Initial workup

PATIENT HISTORY. The doctor will ask the patient specific questions about the location of the pain, its characteristics, its onset, and the body positions or activities that make it better or worse. If the doctor suspects that the pain is referred from other organs, he or she will ask about a history of diabetes, peptic ulcers, kidney stones, urinary tract infections, or heart murmurs.

PHYSICAL EXAMINATION. The doctor will examine the patient's back and hips to check for conditions that require surgery or emergency treatment. The examination includes several tests that involve moving the patient's legs in specific positions to test for nerve root irritation or disk herniation. The flexibility of the lumbar vertebrae may be measured to rule out ankylosing spondylitis.

Imaging studies

Imaging studies are not usually performed on patients whose history and physical examination suggest routine muscle strain or overuse. X rays are ordered for patients whose symptoms suggest cancer, infection, inflammation, pelvic or abdominal disease, or bone fractures. MRIs are usually ordered only for patients with certain types of masses or tumors.

It is important to know that the appearance of some abnormalities on imaging studies of the lower back does not necessarily indicate that they cause the pain. Many patients have minor deformities that do not create symptoms. The doctor must compare the results of imaging studies very carefully with information from the patient's history and physical examination.

Treatment

All forms of treatment of low back pain are aimed either at symptom relief or to prevent interference with the processes of healing. None of these methods appear to speed up healing.

Acute pain

Acute back pain is treated with nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, muscle relaxants, or aspirin. Applications of heat or cold compresses are also helpful to most patients. If the patient has not experienced some improvement after several weeks of treatment, the doctor will reinvestigate the cause of the pain.

Chronic pain

Patients with chronic back pain are treated witha combination of medications, physical therapy, andoccupational or lifestyle modification. The medicationsgiven are usually NSAIDs, although patients withhypertension, kidney problems, or stomach ulcers should not take these drugs. Patients who take NSAIDs for longer than six weeks should be monitored periodically for complications.

Physical therapy for chronic low back pain usually includes regular exercise for fitness and flexibility, and massage or application of heat if necessary.

Lifestyle modifications include giving up smoking, weight reduction (if necessary), and evaluation of the patient's occupation or other customary activities.

Patients with herniated disks are treated surgically if the pain does not respond to medication.

Patients with chronic low back pain sometimes-benefit from pain management techniques, including biofeedback, acupuncture, and chiropractic manipulation of the spine.

Psychotherapy is recommended for patients whose back pain is associated with a somatoform, anxiety, or depressive disorder.

Low back pain with leg involvement

Treatment of sciatica and other disorders that involve the legs may include NSAIDs. Patients with long-standing sciatica or spinal stenosis that do not respond to NSAIDs are treated surgically. Although some doctors use cortisone injections to relieve the pain, this form of treatment is still debated.

Alternative treatment

A thorough differential diagnosis is important before any treatment is considered. There are times when alternative therapies are the most beneficial, and other times when more invasive treatments are needed.

Chiropractic

Chiropractic treats patients by manipulating or adjusting sections of the spine. It is one of the most popular forms of alternative treatment in the United States for relief of back pain caused by straining or lifting injuries. Some osteopathic physicians, physical therapists, and naturopathic physicians also use spinal manipulation to treat patients with low back pain.

Traditional Chinese medicine

Practitioners of traditional Chinese medicine treat low back pain with acupuncture, tui na (push-and-rub) massage, and the application of herbal poultices.

Herbal medicine

Herbal medicine can utilize a variety of antispasmodic herbs in combination to help relieve low back pain due to spasm. Lobelia (Lobelia inflata ) and myrrh (Commiphora molmol ) are two examples of antispasmodic herbs.

Homeopathy

Homeopathic treatment for acute back pain consists of applications of Arnica oil to the sore area or oral doses of Arnica or Rhus toxicodendron. Bellis perennis is recommended for deep muscle injuries. Other remedies may be recommended based on the symptoms presented by the patient.

Body work and yoga

Massage and the numerous other body work techniques can be very effective in treating low back pain. Yoga, practiced regularly and done properly, can be most useful in preventing future episodes of low back pain.

Prognosis

The prognosis for most patients with acute low back pain is excellent. About 80% of patients recover completely in 4-6 weeks. The prognosis for recovery from chronic pain depends on the underlying cause.

Prevention

Low back pain due to muscle strain can be prevented by lifestyle choices, including regular physical exercise and weight control, avoiding smoking, and learning the proper techniques for lifting and moving heavy objects. Exercises designed to strengthen the muscles of the lower back, and chairs or car seats with lumbar supports are also recommended.

Resources

BOOKS

Hellman, David B. "Arthritis & Musculoskeletal Disorders." In Current Medical Diagnosis and Treatment, 1998, edited by Stephen McPhee, et al., 37th ed. Stamford: Appleton & Lange, 1997.

KEY TERMS

Ankylosing spondylitis A type of arthritis that causes gradual loss of flexibility in the spinal column. It occurs most commonly in males between 16 and 35.

Cauda equina The roots of the spinal nerves controlling movement and sensation in the legs. These nerve roots are located in the lower spine and resemble a horse's tail (cauda equina in Latin).

Chiropractic A method of treatment based on the interactions of the spine and the nervous system. Chiropractors adjust or manipulate segments of the patient's spinal column in order to relieve pain.

Lumbar spine The segment of the human spine above the pelvis that is involved in low back pain. There are five vertebrae, or bones, in the lumbar spine.

Radicular Pain that is caused by the root of a nerve.

Referred pain Pain that is experienced in one part of the body but originates in another organ or area. The pain is referred because the nerves that supply the damaged organ enter the spine in the same segment as the nerves that supply the area where the pain is felt.

Sciatica Pain caused by irritation of the sciatic nerve. Sciatica is felt in the lower back, the buttocks, and the backs of the upper legs.

Spinal stenosis A form of sciatica that is caused by a narrowing of the spinal canal in the lumbar vertebrae. The narrowing puts pressure on the roots of the sciatic nerve.

Low Back Pain

views updated May 11 2018

Low back pain

Definition

Low back pain is a common musculoskeletal symptom that may be either acute or chronic. It may be caused by a variety of diseases and disorders that affect the lumbar spine. Low back pain is often accompanied by sciatica , which is pain that involves the sciatic nerve and is felt in the lower back, the buttocks, and the backs of the thighs.

Description

Low back pain is a symptom that affects 80% of the general United States population at some point in life with sufficient severity to cause absence from work. It is the second most common reason for visits to primary care doctors, and is estimated to cost the American economy $75 billion every year.

Low back pain may be experienced in several different ways:

  • Localized. In localized pain the patient will feel soreness or discomfort when the doctor palpates, or presses on, a specific surface area of the lower back.
  • Diffuse. Diffuse pain is spread over a larger area and comes from deep tissue layers.

  • Radicular. The pain is caused by irritation of a nerve root. Sciatica is an example of radicular pain.
  • Referred. The pain is perceived in the lower back but is caused by inflammation elsewhere-often in the kidneys or lower abdomen.

Causes and Symptoms

Acute pain

Acute pain in the lower back that does not extend to the leg is most commonly caused by a sprain or muscle tear, usually occurring within 24 hours of heavy lifting or overuse of the back muscles. The pain is usually localized, and there may be muscle spasms or soreness when the doctor touches the area. The patient usually feels better when resting.

Chronic pain

Chronic low back pain has several different possible causes:

MECHANICAL Chronic strain on the muscles of the lower backmay be caused by obesity ; pregnancy;or job-related stooping, bending, or other stressful postures.

MALIGNANCY Low back pain at night that is not relieved by lying down may be caused by a tumor in the cauda equina (the roots of the spinal nerves controlling sensation in and movement of the legs), or a cancer that has spread to the spine from the prostate, breasts, or lungs. The risk factors for the spread of cancer to the lower back include a history of smoking , sudden weight loss , and age over 50.

ANKYLOSING SPONDYLITIS Ankylosing spondylitis is a form of arthritis that causes chronic pain in the lower back. The pain is made worse by sitting or lying down and improves when the patient gets up. It is most commonly seen in males between 16 and 35. Ankylosing spondylitis is often confused with mechanical back pain in its early stages.

HERNIATED SPINAL DISK Disk herniation is a disorder in which a spinal disk begins to bulge outward between the vertebrae. Herniated or ruptured disks are a common cause of chronic low back pain in adults.

PSYCHOGENIC Back pain that is out of proportion to a minor injury, or that is unusually prolonged, may be associated with a somatoform disorder or other psychiatric disturbance.

Low back pain with leg involvement

Low back pain that radiates down the leg usually indicates involvement of the sciatic nerve. The nerve can be pinched or irritated by herniated disks, tumors of the cauda equina, abscesses in the space between the spinal cord and its covering, spinal stenosis , and compression fractures. Some patients experience numbness or weakness of the legs as well as pain.

Diagnosis

The diagnosis of low back pain can be complicated. Most cases are initially evaluated by primary care physicians rather than by specialists.

Initial workup

PATIENT HISTORY The doctor will ask the patient specific questions about the location of the pain, its

characteristics, its onset, and the body positions or activities that make it better or worse. If the doctor suspects that the pain is referred from other organs, he or she will ask about a history of diabetes, peptic ulcers, kidney stones , urinary tract infections, or heart murmurs.

PHYSICAL EXAMINATION The doctor will examine the patient's back and hips to check for conditions that require surgery or emergency treatment. The examination includes several tests that involve moving the patient's legs in specific positions to test for nerve root irritation or disk herniation. The flexibility of the lumbar vertebrae may be measured to rule out ankylosing spondylitis.

Imaging studies

Imaging studies are not usually performed on patients whose history and physical examination suggest routine muscle strain or overuse. X rays are ordered for patients whose symptoms suggest cancer, infection, inflammation, pelvic or abdominal disease, or bone fractures. MRIs are usually ordered only for patients with certain types of masses or tumors.

It is important to know that the appearance of some abnormalities on imaging studies of the lower back does not necessarily indicate that they cause the pain. Many patients have minor deformities that do not create symptoms. The doctor must compare the results of imaging studies very carefully with information from the patient's history and physical examination.

Treatment

All forms of treatment of low back pain are aimed either at symptom relief or to prevent interference with the processes of healing. None of these methods appear to speed up healing.

Acute pain

Acute back pain is treated with nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, muscle relaxants , or aspirin . Applications of heat or cold compresses are also helpful to most patients. If the patient has not experienced some improvement after several weeks of treatment, the doctor will reinvestigate the cause of the pain.

Chronic pain

Patients with chronic back pain are treated witha combination of medications, physical therapy, andoccupational or lifestyle modification. The medications given are usually NSAIDs, although patients withhypertension, kidney problems, or stomach ulcers should not take these drugs. Patients who take NSAIDs for longer than six weeks should be monitored periodically for complications.

Physical therapy for chronic low back pain usually includes regular exercise for fitness and flexibility, and massage or application of heat if necessary.

Lifestyle modifications include giving up smoking, weight reduction (if necessary), and evaluation of the patient's occupation or other customary activities.

Patients with herniated disks are treated surgically if the pain does not respond to medication.

Patients with chronic low back pain sometimes benefit from pain management techniques, including biofeedback, acupuncture , and chiropractic manipulation of the spine.

Psychotherapy is recommended for patients whose back pain is associated with a somatoform, anxiety , or depressive disorder.

Low back pain with leg involvement

Treatment of sciatica and other disorders that involve the legs may include NSAIDs. Patients with long-standing sciatica or spinal stenosis that do not respond to NSAIDs are treated surgically. Although some doctors use cortisone injections to relieve the pain, this form of treatment is still debated.

Alternative treatment

A thorough differential diagnosis is important before any treatment is considered. There are times when alternative therapies are the most beneficial, and other times when more invasive treatments are needed.

Chiropractic

Chiropractic treats patients by manipulating or adjusting sections of the spine. It is one of the most popular forms of alternative treatment in the United States for relief of back pain caused by straining or lifting injuries. Some osteopathic physicians, physical therapists, and naturopathic physicians also use spinal manipulation to treat patients with low back pain.

Traditional Chinese medicine

Practitioners of traditional Chinese medicine treat low back pain with acupuncture, tui na (push-and-rub) massage, and the application of herbal poultices.

Herbal medicine

Herbal medicine can utilize a variety of antispasmodic herbs in combination to help relieve low back pain due to spasm. Lobelia (Lobelia inflata) and myrrh (Commiphora molmol) are two examples of antispasmodic herbs.

KEY TERMS

Ankylosing spondylitis —A type of arthritis that causes gradual loss of flexibility in the spinal column. It occurs most commonly in males between 16 and 35.

Cauda equina —The roots of the spinal nerves controlling movement and sensation in the legs. These nerve roots are located in the lower spine and resemble a horse's tail (cauda equina in Latin).

Chiropractic —A method of treatment based on the interactions of the spine and the nervous system. Chiropractors adjust or manipulate segments of the patient's spinal column in order to relieve pain.

Lumbar spine —The segment of the human spine above the pelvis that is involved in low back pain. There are five vertebrae, or bones, in the lumbar spine.

Radicular —Pain that is caused by the root of a nerve.

Referred pain —Pain that is experienced in one part of the body but originates in another organ or area. The pain is referred because the nerves that supply the damaged organ enter the spine in the same segment as the nerves that supply the area where the pain is felt.

Sciatica —Pain caused by irritation of the sciatic nerve. Sciatica is felt in the lower back, the buttocks, and the backs of the upper legs.

Spinal stenosis —A form of sciatica that is caused by a narrowing of the spinal canal in the lumbar vertebrae. The narrowing puts pressure on the roots of the sciatic nerve.

Homeopathy

Homeopathic treatment for acute back pain consists of applications of Arnica oil to the sore area or oral doses of Arnica or Rhus toxicodendron. Bellis perennis is recommended for deep muscle injuries. Other remedies may be recommended based on the symptoms presented by the patient.

Body work and yoga

Massage and the numerous other body work techniques can be very effective in treating low back pain. Yoga , practiced regularly and done properly, can be most useful in preventing future episodes of low back pain.

Prognosis

The prognosis for most patients with acute low back pain is excellent. About 80% of patients recover completely in 4-6 weeks. The prognosis for recovery from chronic pain depends on the underlying cause.

Prevention

Low back pain due to muscle strain can be prevented by lifestyle choices, including regular physical exercise and weight control, avoiding smoking, and learning the proper techniques for lifting and moving heavy objects. Exercises designed to strengthen the muscles of the lower back, and chairs or car seats with lumbar supports are also recommended.

Resources

BOOKS

Hellman, David B. “Arthritis & Musculoskeletal Disorders.” In Current Medical Diagnosis and Treatment, 1998, edited by Stephen McPhee, et al., 47th ed. New York: McGraw Hill.

Rebecca J. Frey Ph.D.

Low Back Pain

views updated May 29 2018

Low Back Pain

The low back is the region of the body situated above the pelvis and the hips. This part of the body is also known as the lumbar region. The skeletal support for the low back is provided by the lumbar spine, the assembly of five vertebrae that are connected to the pelvis by the bony structure known as the sacrum. The lumbar vertebrae are each separated by intravertebral disks, which are composed of a fibrous material, in which a thick gel material is enclosed. The disks act to absorb the forces received by the vertebrae, as well as working to stabilize the lumbar spinal column.

The lumbar spinal column encloses the spinal cord, the transmission route for all signals generated by the brain; it also provides openings in the bony surface of the vertebrae for nerve endings to extend into the tissues of the body from the spinal cord. The lumbar spine is made flexible due to the facet joints, the ligaments that connect the vertebrae one to another. The spinal column is connected to the larger muscle and tendon groups that both support the spine and power the bending, twisting, and turning mechanisms of the low back; the abdominal, gluteal (buttocks), lateral, and oblique muscle groups work in concert to facilitate low back movement.

As the lumbar vertebrae are both the weight-bearing segment of the spine as well as essential to flexion and extension motions, the low back is subject to significant stresses in both sport as well as everyday human activity that often lead to injury and consequent pain. Low back pain is not restricted to one cause; the condition may be attributed to a number of circumstances, some of which are cumulative and others which are the result of a single physical occurrence.

There are a number of common causes of lower back pain. For example, pain can occur if the low back is subjected to the stresses caused by a slumped posture, or by excessive periods of being seated in a position in which excess body weight rests on the low back where it is not adequately supported, such as in computer use, the lumbar vertebrae and their disks may become damaged. Also, the low back will be more susceptible to strain if it is required to bear additional or excessive body weight for extended periods. Sudden twisting or turning movement is often the cause of low back pain where the low back is already significantly stressed or damaged.

Lifting heavy objects can result in low back pain. If the low back is not in an optimal position at the point when the force is exerted to lift the item, both the muscles and the spine are susceptible to damage. Such injuries occur in athletic and non-athletic circumstances, particularly where the movement is attempted without the benefit of a proper warm up and stretching of the low back structure. In addition, if someone is struck in the lower back area, the force associated with the blow, such as an ice hockey body check, or a tackle in other sports, can damage the low back. In extreme cases, the force can produce a fracture of one of the vertebrae. And finally, when a blow is given to either the top of the spine that radiates down the spinal column to the low back, or a similar radiation of force from a blow delivered at the buttocks and pelvis that radiates upward.

In rare circumstances, low back pain may be triggered through no physical cause; such cases often involve a problem with a nerve in the vicinity.

The most common cause of low back pain is a strain in the muscles adjacent to the lumbar spine. In many cases, such pain will resolve itself through rest. In some cases, nonsteroidal anti-inflammatory drugs (NSAID) are used to assist in the management of the condition. The follow-up to ensure the prevention of this type of injury will include an emphasis on proper stretching of the low back muscle groups, as well as the technique employed in all manner of twisting, turning, and lifting. A back brace, a flexible assistive device worn around the midsection, may also be used in the rehabilitation of this type of injury.

A medical examination may reveal the existence of a degenerative disk disease (DDD); the presence of DDD is not itself evidence of the cause of back pain, as many people have the condition without limitation of movement. In many cases, DDD, which includes a narrowing of the disk space, precipitates back pain.

A failure to properly warm up and stretch the muscles and the structure of the lower back is the leading cause of injury to this part of the anatomy. Stretched and properly stimulated muscles, along with elevated heart rate and respiration that accompanies a proper warm up, will prepare the low back, especially where it will be the subject of explosive lifting movements or twisting motions.

see also Back injuries; Hip and pelvis anatomy and physiology; Neck injuries.