Low back pain

See also back pain

Low back pain
ICD-10	M54.4-M54.5
ICD-9	724.2
MedlinePlus	003108
eMedicine	pmr/73
MeSH	D017116

Template:Search infobox Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Associate Editor-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]

Please Join in Editing This Page and Apply to be an Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [3] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.

Low back pain is a common musculoskeletal disorder which affects the lumbar segment of the spine. It can be either acute, subacute or chronic in its clinical presentation. Typically, the symptoms of low back pain do show significant improvement within two to three months from its onset. In a significant number of individuals, low back pain tends to be recurrent in nature with a waxing and waning quality to it. In a small proportion of sufferers this condition can become chronic. Population studies show that back pain affects most adults at some stage in their life and accounts for more sick leave and disability than any other single medical condition.

An acute lower back injury may be caused by a traumatic event, like a car accident or a fall. It occurs suddenly and its victims will usually be able to pinpoint exactly when it happened. In acute cases, the structures damaged will more than likely be soft tissue like muscles, ligaments and tendons. With a serious accident or due to osteoporosis or other causes of weakened vertebral bones, vertebral fractures in the lumbar spine may also occur. At the lowest end of the spine, some patients may have tailbone pain (also called coccyx pain or coccydynia). Others may have pain from their sacroiliac joint at the bottom of the lumbar spine, called sacroiliac joint dysfunction.

Chronic lower back pain usually has a more insidious onset, occurring over a long period of time. Physical causes may include osteoarthritis, rheumatoid arthritis, degeneration of the discs between the vertebrae, or a spinal disc herniation, a vertebral fracture (such as from osteoporosis), or rarely, a tumor (including cancer) or infection. The cause may also be psychological or emotional or due to other non-anatomical factors.

Normal Anatomy and Function

The back is an intricate structure of bones, muscles, and other tissues that form the posterior part of the body’s trunk, from the neck to the pelvis. The centerpiece is the spinal column, which not only supports the upper body’s weight but 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 — the vertebrae — that form the spinal column, also known as the spine. Each of these bones contains a roundish 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 (“roots”) 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 lumbar vertebrae (labeled L1–L5), which we know as the lower back, 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.

Pathophysiology

As people age, bone strength and muscle elasticity and tone tend to decrease. The discs begin to lose fluid and flexibility, which decreases their ability to cushion the vertebrae.

Pain can occur when, for example, someone lifts something too heavy or overstretches, causing a sprain, strain, or spasm in one of the muscles or ligaments in the back. If the spine becomes overly strained or compressed, a disc may rupture or bulge outward. This rupture may put pressure on one of the more than 50 nerves rooted to the spinal cord that control body movements and transmit signals from the body to the brain. 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 a pinched nerve or other serious condition. People with diabetes may have severe back pain or pain radiating down the leg related to neuropathy. People with these symptoms should contact a doctor immediately to help prevent permanent damage.

Risk Factors

Nearly everyone has low back pain sometime. Men and women are equally affected. It occurs most often between ages 30 and 50, due in part to the aging process but also as a result of sedentary life styles with too little (sometimes punctuated by too much) exercise. 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 cause 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 13,260 injuries related to backpacks were treated at doctors’ offices, clinics, and emergency rooms in the year 2000. 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.

Differential Diagnosis of Causes of Low back pain

Possible causes of low back pain:

• Mechanical:
  • Apophyseal osteoarthritis
  • Diffuse Idiopathic Skeletal Hyperostosis
  • Degenerative Discs
  • Scheuermann's kyphosis
  • Spinal disc herniation (slipped disc)
  • Spinal stenosis
  • Spondylolisthesis and other congenital abnormalities
  • Fractures
  • Non-specific muscular or ligamentous strains or sprains
  • Leg Length Difference
  • Restricted hip motion
  • Misaligned pelvis - pelvic obliquity, anteversion or retroversion

• Inflammatory:
  • Seronegative spondylarthritides (e.g. ankylosing spondylitis)
  • Rheumatoid arthritis
  • Infection - epidural abscess or osteomyelitis

• Neoplastic:
  • Bone tumors (primary or metastatic)
  • Intradural Spinal tumors

• Metabolic:
  • Osteoporotic fractures
  • Osteomalacia
  • Ochronosis
  • Chondrocalcinosis

• Paget's disease

• Referred pain:
  • Pelvic/abdominal disease
  • Posture

• Depression
• oxygen deprivation

Diagnosis

Diagnosing the underlying cause of low back pain is usually done by a medical doctor, osteopathic physican, physiotherapist (physical therapist) or by a chiropractor. Often, getting a diagnosis of the underlying cause of low back pain and/or related symptoms is quite complex. A complete diagnosis is usually made through a combination of a patient's medical history, physical examination, and, when necessary, diagnostic testing, such as an MRI scan or x-ray. There are a number of health care professionals who may specialize in diagnosing and treating low back pain, including chiropractors, osteopathic physicians, physical therapists (physiotherapists), physical therapy physicians, anesthesiologists/pain medicine physicians, and orthopedic surgeons or neurosurgeons.

Treatments

The course of treatment for low back pain will usually be dictated by the clinical diagnosis of the underlying cause of the pain.

Conservative treatment

For the vast majority of patients, low back pain can be treated with non-surgical care. For those with acute, short-term back pain, certain home remedies may be effective. ClinicalEvidence.com has systematically reviewed randomized controlled trials published through April, 2004 and concluded:

Treatments likely to be beneficial

• Advice to stay active.
• Analgesics (pain medications), such as NSAIDs or acetaminophen.
• Spinal manipulation for acute or chronic pain. A clinical prediction rule can guide who is most likely to respond to manipulation.
• Muscle relaxants for acute or chronic pain.
• Antidepressants for chronic low back pain.
• Exercise for chronic pain.
• Intensive multidisciplinary treatment programs may help subacute or chronic low back pain.
• Behavioral therapy
• Acupuncture may help chronic pain; however, a more recent randomized controlled trial suggested significant difference between real and sham acupuncture.

Other treatments

Additional treatments have been more recently reviewed by the Cochrane Collaboration:

• Massage therapy may benefit some patients (PMID 12076429)
• Ice and/or heat application (or moist heat) has uncertain benefit (PMID 16437495).

Individual randomized controlled trials, thus interpretation may be subject to publication bias, also confounded by absence of double blinding have shown benefit for:

• Viniyoga (PMID 16365466), Iyengar (PMID 15836974), and Hatha yoga (PMID 15055095 - small trial).
• Correcting leg length difference may help (PMID 16271551). To correct leg length difference, insert a hard rubber or cork heel pad into the shoe of the short leg if the difference between the two legs is 3/8ths inch or less. If more, have a shoe repairman build up the sole and heel. Taper the toe to avoid tripping. If more than 3/4 inch, start with 1/2 of what you need so that your body can adjust.
• Muscle Energy Technique (MET) may help (PMID 14524509 - small study)

Other treatments that were not reviewed are

• Education and attitude adjustment (TMS)
• Increasing internal hip rotation
• Increase internal hip rotation with stretching or connective tissue massage

Because of variations in clinical study methodology, a review of clinical studies in any one area is not necessarily conclusive.

For any one condition, it may be necessary to try a variety of treatments in order to find the best one (or combination) to best manage the pain. In almost all cases, physical therapy and/or a regular exercise program that includes stretching, strengthening and low impact cardio conditioning will be part of the treatment and rehabilitation program.

The role of narcotics for chronic low back pain is uncertain.

Surgery

Lumbar surgery is indicated when conservative treatment is not effective in reducing pain or when the patient develops progressive and functionally limiting neurologic symptoms such as leg weakness, bladder or bowel incontinence, which can be seen with severe lumbar disc herniation, spinal abscess or cauda equina syndrome. Other possible indications for surgery include:

• Severe Degenerative disc disease
• Spinal stenosis
• Spondylolisthesis
• Scoliosis
• Compression fracture
• Spinal instability
• Spinal trauma
• Spinal malignancy (cancer)
• Spinal hematoma

The most common types of low back surgery include microdiscectomy, discectomy, laminectomy, foraminotomy, or spinal fusion. Another less invasive surgical technique consists of an implantation of a spinal cord stimulator and typically is used for symptoms of chronic radiculopathy (sciatica). Lumbar artificial disc replacement is a newer surgical technique for treatment of degenerative disc disease, as are a variety of surgical procedures aimed at preserving motion in the spine.

See also

• Back pain
• Upper back pain
• Chronic pain
• Lumbar disc herniation
• Degenerative disc disease
• Coccydynia (coccyx pain, tailbone pain)
• Sciatica
• Failed back syndrome
• Bertolotti's syndrome

External links

• Non-Invasive Lower Back Pain Relief
• Lower Back Pain Prevention
• Back Pain, Neck Pain, Low Back Pain
• Stress related back pain
• Low Back Pain - Information for Patients
• Coccydynia (coccyx pain, tailbone pain) at eMedicine
• Low Back Pain Resource Center - SpineUniverse
• Back pain and neck pain information for patients
• Tailbone pain (coccyx pain, coccydynia) article at eMedicine
• Lumbago forum (in French)
• Back Pain Information Web

Template:WikiDoc Sources