If you have had lower back pain, you are not alone. Back pain is one of most common reasons people see a doctor or miss days at work. Even school-age children can have back pain.
Back pain can range in intensity from a dull, constant ache to a sudden, sharp or shooting pain. It can begin suddenly as a result of an accident or by lifting something heavy, or it can develop over time as we age. Getting too little exercise followed by a strenuous workout also can cause back pain.
There are two types of back pain:
- Acute, or short-term back pain lasts a few days to a few weeks. Most low back pain is acute. It tends to resolve on its own within a few days with self-care and there is no residual loss of function. In some cases a few months are required for the symptoms to disappear.
- Chronic back pain is defined as pain that continues for 12 weeks or longer, even after an initial injury or underlying cause of acute low back pain has been treated. About 20 percent of people affected by acute low back pain develop chronic low back pain with persistent symptoms at one year. Even if pain persists, it does not always mean there is a medically serious underlying cause or one that can be easily identified and treated. In some cases, treatment successfully relieves chronic low back pain, but in other cases pain continues despite medical and surgical treatment.
What structures make up the back?
The lower back—where most back pain occurs—includes the five vertebrae (referred to as L1-L5) in the lumbar region, which supports much of the weight of the upper body. The spaces between the vertebrae are maintained by round, rubbery pads called intervertebral discs that act like shock absorbers throughout the spinal column to cushion the bones as the body moves. Bands of tissue known as ligaments hold the vertebrae in place, and tendons attach the muscles to the spinal column. Thirty-one pairs of nerves are rooted to the spinal cord and they control body movements and transmit signals from the body to the brain.
Other regions of vertebrate are cervical (in the neck), thoracic (upper back), and sacral and coccygeal (below the lumbar area) segments.
What can cause lower back pain?
Most acute low back pain is mechanical in nature, meaning that there is a disruption in the way the components of the back (the spine, muscle, intervertebral discs, and nerves) fit together and move. Some examples of mechanical causes of low back pain include:
Congenital
- Skeletal irregularities such as scoliosis (a curvature of the spine), lordosis (an abnormally exaggerated arch in the lower back), kyphosis (excessive outward arch of the spine), and other congenital anomalies of the spine.
- Spina bifida which involves the incomplete development of the spinal cord and/or its protective covering and can cause problems involving malformation of vertebrae and abnormal sensations and even paralysis.
Injuries
- Sprains (overstretched or torn ligaments), strains (tears in tendons or muscle), and spasms (sudden contraction of a muscle or group of muscles)
- Traumatic Injury such as from playing sports, car accidents, or a fall that can injure tendons, ligaments, or muscle causing the pain, as well as compress the spine and cause discs to rupture or herniate.
Degenerative problems
- Intervertebral disc degeneration which occurs when the usually rubbery discs wear down as a normal process of aging and lose their cushioning ability.
- Spondylosis the general degeneration of the spine associated with normal wear and tear that occurs in the joints, discs, and bones of the spine as people get older.
- Arthritis or other inflammatory disease in the spine, including osteoarthritis and rheumatoid arthritis as well as spondylitis, an inflammation of the vertebrae.
Nerve and spinal cord problems
- Spinal nerve compression, inflammation and/or injury
- Sciatica (also called radiculopathy), caused by something pressing on the sciatic nerve that travels through the buttocks and extends down the back of the leg. People with sciatica may feel shock-like or burning low back pain combined with pain through the buttocks and down one leg.
- Spinal stenosis, the narrowing of the spinal column that puts pressure on the spinal cord and nerves
- Spondylolisthesis, which happens when a vertebra of the lower spine slips out of place, pinching the nerves exiting the spinal column
- Herniated or ruptured discs can occur when the intervertebral discs become compressed and bulge outward
- Infections involving the vertebrae, a condition called osteomyelitis; the intervertebral discs, called discitis; or the sacroiliac joints connecting the lower spine to the pelvis, called sacroiliitis
- Cauda equina syndrome occurs when a ruptured disc pushes into the spinal canal and presses on the bundle of lumbar and sacral nerve roots. Permanent neurological damage may result if this syndrome is left untreated.
- Osteoporosis (a progressive decrease in bone density and strength that can lead to painful fractures of the vertebrae)
Non-spine sources
- Kidney stones can cause sharp pain in the lower back, usually on one side
- Endometriosis (the buildup of uterine tissue in places outside the uterus)
- Fibromyalgia (a chronic pain syndrome involving widespread muscle pain and fatigue)
- Tumors that press on or destroy the bony spine or spinal cord and nerves or outside the spine elsewhere in the back
- Pregnancy (back symptoms almost always completely go away after giving birth)
What are the risk factors for developing low back pain?
Anyone can have back pain. Factors that can increase the risk for low back pain include:
Age: The first attack of low back pain typically occurs between the ages of 30 and 50, and back pain becomes more common with advancing age. Loss of bone strength from osteoporosis can lead to fractures, and at the same time, muscle elasticity and tone decrease. The intervertebral discs begin to lose fluid and flexibility with age, which decreases their ability to cushion the vertebrae. The risk of spinal stenosis also increases with age.
Fitness level: Back pain is more common among people who are not physically fit. Weak back and abdominal muscles may not properly support the spine. “Weekend warriors”—people who go out and exercise a lot after being inactive all week—are more likely to suffer painful back injuries than people who make moderate physical activity a daily habit. Studies show that low-impact aerobic exercise can help maintain the integrity of intervertebral discs.
Weight gain: Being overweight, obese, or quickly gaining significant amounts of weight can put stress on the back and lead to low back pain.
Genetics: Some causes of back pain, such as ankylosing spondylitis (a form of arthritis that involves fusion of the spinal joints leading to some immobility of the spine), have a genetic component.
Job-related factors: Having a job that requires heavy lifting, pushing, or pulling, particularly when it involves twisting or vibrating the spine, can lead to injury and back pain. Working at a desk all day can contribute to pain, especially from poor posture or sitting in a chair with not enough back support.
Mental health: Anxiety and depression can influence how closely one focuses on their pain as well as their perception of its severity. Pain that becomes chronic also can contribute to the development of such psychological factors. Stress can affect the body in numerous ways, including causing muscle tension.
Smoking: It can restrict blood flow and oxygen to the discs, causing them to degenerate faster.
Backpack overload in children: A backpack overloaded with schoolbooks and supplies can strain the back and cause muscle fatigue.
Psychological factors: Mood and depression, stress, and psychological well-being also can influence the likelihood of experiencing back pain.
For full facts list visit https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Low-Back-Pain-Fact-Sheet