imaging may be recommended. these red flags include: history of cancer unexplained weight loss immunosuppression urinary infection intravenous drug use prolonged use of corticosteroids back pain not improved with conservative management history of significant trauma minor fall or heavy lift in a potentially osteoporotic or elderly individual acute onset of urinary retention, overflow incontinence, loss of anal sphincter tone, or fecal incontinence saddle anesthesia global or progressive motor weakness in the lower limbs prevention moderate-quality evidence exists that suggests that the combination of education and exercise may reduce an individual's risk of developing an episode of low back pain. lesser-quality evidence points to exercise alone as a possible deterrent to the risk of the condition. management nonspecific pain patients with uncomplicated back pain should be encouraged to remain active and to return to normal activities. the management goals when treating back pain are to achieve maximal reduction in pain intensity as rapidly as possible, to restore the individual's ability to function in everyday activities, to help the patient cope with residual pain, to assess for side effects of therapy and to facilitate the patient's passage through the legal and socioeconomic impediments to recovery. for many, the goal is to keep the pain at a manageable level to progress with rehabilitation, which then can lead to long-term pain relief. also, for some people the goal is to use nonsurgical therapies to manage the pain and avoid major surgery, while for others surgery may represent the quickest path to pain relief. not all treatments work for all conditions or for all individuals with the same condition, and many must try several treatment options to determine what works best for them. the present stage of the condition (acute or chronic) is also a determining factor in the choice of treatment. only a minority of people with back pain (most estimates are 1–10%) require surgery. nonmedical back pain is generally first treated with nonpharmacological therapy, as it typically resolves without the use of medication. superficial heat and massage, acupuncture and spinal manipulation therapy may be recommended. heat therapy is useful for back spasms or other conditions. a review concluded that heat therapy can reduce symptoms of acute and subacute low-back pain. regular activity and gentle stretching exercises is encouraged in uncomplicated back pain and is associated with better long-term outcomes. physical therapy to strengthen the muscles in the abdomen and around the spine may also be recommended. these exercises are associated with better patient satisfaction, although they have not been shown to provide functional improvement. however, one review found that exercise is effective for chronic back pain but not for acute pain. exercise should be performed under the supervision of a healthcare professional. massage therapy may provide short-term pain relief, but not functional improvement, for those with acute lower back pain. it may also offer short-term pain relief and functional improvement for those with long-term (chronic) and subacute lower pack pain, but this benefit does not appear to be sustained after six months of treatment. there do not appear to be any serious adverse effects associated with massage. acupuncture may provide some relief for back pain. however, further research with stronger evidence is needed. spinal manipulation appears to provide similar effects to other recommended treatments for chronic low back pain. there is no evidence it is more effective than other therapies or sham, or as an adjunct to other treatments, for acute low back pain "back school" is an intervention that consists of both education and physical exercises. there is no strong evidence supporting the use of back school for treating acute, subacute, or chronic non-specific back pain. insoles appear to be an ineffective treatment intervention. while traction for back pain is often used in combination with other approaches, there appears to be little or no impact on pain intensity, functional status, global improvement or return to work. medication if nonpharmacological measures are ineffective, medication may be administered. non-steroidal anti-inflammatory drugs (nsaids) are typically attempted first. nsaids have been proven more effective than placebo, and are usually more effective than paracetamol (acetaminophen). long-term use of opioids has not been tested to determine whether it is effective or safe for treating chronic lower back pain. for severe back pain not relieved by nsaids or acetaminophen, opioids may be used. opioids may not be better than nsaids or antidepressants for chronic back pain with regard to pain relief and gain of function. skeletal muscle relaxers may also be used. their short-term use has been proven effective in the relief of acute back pain. however, the evidence of this effect has been disputed, and these medications do have negative side effects. for patients with nerve root pain and acute radiculopathy, there is evidence that a single dose of steroids, such as dexamethasone, may provide pain relief. epidural corticosteroid injection (esi) is a procedure in which steroid medications are injected into the epidural space. the steroid medications reduce inflammation and thus decrease pain and improve function. esi has long been used to both diagnose and treat back pain, although recent studies have shown a lack of efficacy in treating low back pain. surgery surgery for back pain is typically used as a last resort, when serious neurological deficit is evident. a 2009 systematic review of back surgery studies found that, for certain diagnoses, surgery is moderately better than other common treatments, but the benefits of surgery often decline in the long term. surgery may sometimes be appropriate for people with severe myelopathy or cauda equina syndrome. causes of neurological deficits can include spinal disc herniation, spinal stenosis, degenerative disc disease, tumor, infection, and spinal hematomas, all of which can impinge on the nerve roots around the spinal cord. there are multiple surgical options to treat back pain, and these options vary depending on the cause of the pain. when a herniated disc is compressing the nerve roots, hemi- or partial- laminectomy or discectomy may be performed, in which the material compressing on the nerve is removed. a mutli-level laminectomy can be done to widen the spinal canal in the case of spinal stenosis. a foraminotomy or foraminectomy may also be necessary, if the vertebrae are causing significant nerve root compression. a discectomy is performed when the intervertebral disc has herniated or torn. it involves removing the protruding disc, either a portion of it or all of it, that is placing pressure on the nerve root. total disc replacement can also be performed, in which the source of the pain (the damaged disc) is removed and replaced, while maintaining spinal mobility. when an entire disc is removed (as in discectomy), or when the vertebrae are unstable, spinal fusion surgery may be performed. spinal fusion is a procedure in which bone grafts and metal hardware is used to fix together two or more vertebrae, thus preventing the bones of the spinal column from compressing on the spinal cord or nerve roots. if infection, such as a spinal epidural abscess, is the source of the back pain, surgery may be indicated when a trial of antibiotics is ineffective. surgical evacuation of spinal hematoma can also be attempted, if the blood products fail to break down on their own. pregnancy about 50% of women experience low back pain during pregnancy. some studies have suggested that women who have experienced back pain before pregnancy are at a higher risk of experiencing back pain during pregnancy. it may be severe enough to cause significant pain and disability in as many as one third of pregnant women. back pain typically begins at approximately 18 weeks of gestation and peaks between 24 and 36 weeks. approximately 16% of women who experience back pain during pregnancy report continued back pain years after pregnancy, indicating that those with significant back pain are at greater risk of back pain following pregnancy. biomechanical factors of pregnancy shown to be associated with back pain include increased curvature of the lower back, or lumbar lordosis, to support the added weight on the abdomen. also, the hormone relaxin is released during pregnancy, which softens the structural tissues in the pelvis and lower back to prepare for vaginal delivery. this softening and increased flexibility of the ligaments and joints in the lower back can result in pain. back pain in pregnancy is often accompanied by radicular symptoms, suggested to be caused by the baby pressing on the sacral plexus and lumbar plexus in the pelvis. typical factors aggravating the back pain of pregnancy include standing, sitting, forward bending, lifting and walking. back pain in pregnancy may also be characterized by pain radiating into the thigh and buttocks, nighttime pain severe enough to wake the patient, pain that is increased at night or pain that is increased during the daytime. local heat, acetaminophen (paracetamol) and massage can be used to help relieve pain. avoiding standing for prolonged periods of time is also suggested. economics although back pain does not typically cause permanent disability, it is a significant contributor to physician visits and missed work days in the united states, and is the single leading cause of disability worldwide. the american academy of orthopaedic surgeons report approximately 12 million visits to doctor's offices each year are due to back pain. missed work and disability related to low back pain costs over $50 billion each year in the united states. in the united kingdom in 1998, approximately £1.6 billion per year was spent on expenses related to disability from back pain.