What Is Low Back Pain?

Low back pain explained by San Antonio, Austin, Houston, Dallas Texas top pain doctors

As many as 84% of adults will suffer from low back pain at some point during their lifetime, according to recent prevalence estimates. Furthermore, between 44% and 78% of adults who have suffered with an episode of low back pain will have a reoccurrence of their pain. The Centers for Disease Control and Prevention have reported that low back pain is associated with significant disability and will probably have negative effects on an individual’s levels of functioning at both home and work. In addition to detrimental effects on the lives of affected individuals, low back pain has a significant impact on the economy in the United States, costing approximately $50 billion annually. Low back pain is thought to be the leading cause of decreased work productivity and missed time from work, and is the leading cause of work disability. Furthermore, low back pain increases healthcare utilization rates. It is for all of these reasons combined that low back pain has received considerable attention by researchers recently. Over the past ten years, there has been a significant increase in the number of studies being conducted exploring the prognostic factors of low back pain as well as an increase in studies investigating the efficacy of various treatment methods that are available.

Low back pain is typically classified as either acute or chronic, depending on the duration of a patient’s symptoms. Acute pain is usually short-term pain that lasts between several days and several weeks. Conversely, chronic pain is long-term pain that lasts for a period longer than three months. In some patients, acute low back pain can lead to chronic episodes of low back pain. Generally, chronic pain develops over time and progresses from a dull ache to more severe pain. Approximately 12% of the population is disabled due to their chronic low back pain symptoms. There is little evidence regarding the prevalence rates of non-specific low back pain; however, some suggest that lifetime prevalence rates may be as high as 23%. Non-specific low back pain refers to pain that cannot be attributed to a specific source such as an injury, tumor, or osteoporosis. The high prevalence estimates suggest that a substantial portion of the adult population is forced to cope with pain every day. Furthermore, it is probable that these individuals are not able to maintain a job due to the significant pain that they experience.

Prior to initiating treatment for low back pain, patients need to be properly assessed and the source of pain needs to be accurately identified. The back is a complex structure comprised of various bones, muscles, and other tissues that spans the region from the neck to the pelvic bone. The vertebral column is the boney structure that provides support for the body and helps to protect the spinal cord. The vertebral column consists of individual vertebra which link together to create natural spinal curvatures that allow for flexibility. The natural curvatures of the spine include the cervical curve, thoracic curve, lumbar curve, and sacral curve. Between each vertebra is a cartilage pad known as an intervertebral disc, which provides cushioning and contributes to the general flexibility of the various regions of the spine. Ligaments and muscles are attached to the vertebrae of the vertebral canal and these structures provide mobility and strength for the back. Within the vertebral canal is the delicate spinal cord, which descends from the brain and reaches to just below the rib cage, in most adults. All of the structures of the spinal canal are at risk for damage caused by wear and tear, disease, and acute trauma.

Low Back Pain DiagramLow back pain is described as pain or discomfort that originates in the lower back, particularly in the area just above the inferior gluteal folds and below the costal margin. Additionally, some individuals will report radiating lower extremity pain in addition to their lower back pain. The specific symptoms of low back pain differ among patients, with some patients reporting a widespread, dull ache, and others reporting a localized, sharp stab. While specific symptoms of low back pain differ among patients, common complaints reported by patients include muscle cramping and stiffness, muscle spasm, radiating pain into the lower extremities, tingling, numbness, or weakness, as well as a sensitivity to pressure or touch. A patient’s lower back pain symptoms are expected to fluctuate over time. Some patients may report that their pain is worse upon waking, while others report that it is worse with activity.  Moreover, certain activities such as lifting, bending, and twisting can often lead to increases in low back pain symptoms. In some cases, patients report that certain environmental circumstances may alleviate or exacerbate symptoms.

In order to properly assess a patient presenting with low back pain, the physician will take a brief, detailed history and will likely perform a focused physical examination of the affected area and surrounding structures. The goal of the assessment is to determine the source of an individual’s low back pain as well as to rule out any serious, underlying pathology. The physician also assesses an individual’s risk of suffering with persistent low back pain by asking about certain prognostic factors known as “yellow flags.” The prognostic factors that have been identified as being related to low back pain include work factors, psychosocial distress, pain severity, depressed mood, level of functional impairment, extreme symptom reporting, and patient perception of pain and disability.

Signs that there may be an underlying serious pathology are referred to as “red flags” and include extreme patient age (e.g. younger than 20 years of age, or older than 55 years of age), pain that is non-mechanical, unexplained weight loss, thoracic pain that is worse with coughing, sneezing, or bearing down, prolonged steroid use, history of cancer, structural changes, poor general health, and widespread neurological deficits. Red flags may be a sign of an underlying issue such as a fracture, tumor, inflammatory process, or cauda equina syndrome. However, it is important to understand that patients who exhibit red flags do not necessarily have an underlying condition. However, the existence of red flags suggests that a patient is at an increased risk. If a patient presents with more than one red flag, they should receive further evaluation.

Causes Of Low Back Pain

There are numerous conditions that occur in conjunction with low back pain. Common conditions that are related to low back pain include the following.

  • Herniated disc: This condition is characterized by damage to the intervertebral discs of the spinal column, which causes them to bulge or herniate. The bulging or herniated disc material can cause irritation and inflammation of the surrounding spinal nerves, resulting in severe pain. There is an increased risk of disc herniation with increasing age.
  • Osteoarthritis: This condition is characterized by damage to the cartilage. This damage can occur due to normal wear and tear, disease, or an acute injury. When there is significant cartilage damage, there is a heightened risk of bone rubbing on bone, which can result in significant pain.
  • Fractured vertebrae: This condition is usually the result of extreme force.
  • Compression fracture: This condition is more commonly seen in post-menopausal women who have osteoporosis, and in patients who have a history of prolonged corticosteroid use.
  • Spondylolisthesis: This condition occurs when one vertebrae becomes dislocated and slides off another. It is often categorized as nonspecific low back pain as a large percentage of the patients with this deformity do not have any related symptoms, including pain. It is estimated that approximately 5% of the general population has this deformity.
  • Spinal stenosis: This condition is characterized by a restriction of the spinal canal, which is caused by a narrowing of the spinal column.
  • Spinal deformity: These conditions are genetically linked problems that relate to the curve of the spine, including kyphosis and scoliosis, and generally affect the entire spine. These deformities are relatively rare and while recent prevalence rates are unavailable, early estimates suggest that these deformities occur in 0.8% to 1.9% of the general population.
  • Spinal infections: Some cases of low back pain can be attributed to diseases that have infected the spine. When a patient presents with low back pain in conjunction with a fever, history of recent surgery, history of drug use, or compromised immune system, infection should always be considered as the source of pain.

Various factors have been identified that are associated with an increased risk of developing persistent low back pain, including gender, pain perception, anxiety and depression, as well as employment status. A five-year prospective study investigated prognostic factors that predict long-term outcome in low back pain patients and found that both the patient’s degree of pain intensity and their beliefs regarding the persistent nature of their pain predicted a poor outcome. This poor outcome was seen at both six-month and five-year follow-ups. This suggests that poor outcomes remain consistent over time.

Treatments For Low Back Pain

Low Back PainThere has been a considerable amount of attention focused on low back pain treatments and many of the treatment options that are currently available have undergone intensive investigation prior to receiving empirical support. Due to the nature of low back pain and the diversity of conditions that can cause it, patients are advised to speak with their physician to determine the best course of treatment for management of their low back pain symptoms. Additionally, patients will be able to have their questions and concerns regarding their symptoms addressed by their doctor. Moreover, physicians have access to a multitude of educational resources that can be shared with their patients.

Patients experiencing mild to moderate pain that is not disrupting their day-to-day functioning will likely be advised to attempt conservative treatment options for pain relief before considering more invasive treatment options. Previous research has found that up to 90% of back pain sufferers will report a significant improvement in symptoms by engaging in conservative treatment methods, including chiropractic care and physical therapy.

Chiropractic treatment is an alternative treatment that has been shown to provide significant relief of low back pain, in addition to improving overall health. Chiropractic treatment focuses on the chiropractic manipulation, which is applied by the hands to specific joints of the spine. The chiropractic manipulation is either applied with a high velocity thrust to push a joint beyond its’ normal range of motion, or with a low velocity thrust that occurs within the joint’s normal range of motion. The most common side effect of a chiropractic manipulation is tenderness of the affected area; however other side effects can occur, including headache, fatigue, and discomfort in other areas of the body. These side effects usually occur on the same day as the adjustment and resolve within 24 to 48 hours after treatment.  Rarely, there are serious complications including disc herniation, stroke, and cauda equine syndrome. A thorough history and exam will help to minimize the serious complications of a chiropractic manipulation. Additionally, ensuring that the chiropractor is fully trained and licensed to practice will minimize the risk of adverse events.

At times, in addition to providing patients with treatments for pain relief, a treatment plan may attempt to focus on reducing their impairment level, as well as any accompanying disability. For example, if a patient took a leave from work due to their pain, one of the treatment goals may be to return to work. Reaching disability status can be an exacerbating factor for low back pain by working like a feedback loop. If a patient who is disabled by severe and chronic pain does not make an effort to maintain some mobility, they are at risk for maintaining their own pain symptoms.

The pain and disability that is associated with low back pain does not exclusively emerge due to somatic pathology. It is widely accepted that there are a variety of factors that are involved in the pain that a patient experiences. The severity of pain and degree of impairment that an individual experiences is significantly influenced by their attitudes regarding pain and their beliefs regarding disability. Moreover, psychological distress and response to the onset of pain has been found to be influential. Therefore, these factors can become targets in a treatment plan.

It has been found that patients suffering from chronic low back pain can benefit from utilizing positive reinforcement that rewards healthy behaviors and that implements consequences for pain-causing behaviors. Additionally, patients may be asked to identify their thoughts about their pain and disability as these thoughts may be helping to maintain the patient’s pain levels. It is unknown whether changing an individual’s perceptions of pain can have a significant impact on a patient’s pain levels. However, there is some evidence to support the notion that a change in these perceptions can have other beneficial effects for these patients. An example of this is when a patient’s perception is changed regarding the unremitting nature of their chronic pain; it is likely to result in the patient improving their efforts during physical therapy treatment.

Research has shown that stress and tension have negative effects on an individual’s overall health as well as their ability to cope with disruptions to their body system. Therefore, modification of the patient’s physiological response system may be warranted in some cases. There is some evidence to suggest that biofeedback training can assist individuals in managing their low back pain, as well as helping to relieve tension and stress that often accompanies the pain. Biofeedback training is a non-invasive therapy that helps patients to recognize their physiologic symptoms and teaches them how to modify their responses.

Biofeedback training provides patients with real-time information about their physiologic responses using various psycho-physiological recordings. The devices used to measure these responses were designed to measure slight changes in a patient’s response and to display this information on a computer screen for the patient to see. Biofeedback training involves a number of stress-reducing exercises, which essentially teach the patients how to effectively change their physiologic response system, thereby gaining control over their responses.

Common physiological systems that are utilized during biofeedback training include:

  • Electromyogram (EMG): Provides a measurement of muscular tension
  • Electroencephalography (EEG): Provides a measurement of brain wave activity
  • Electrocardiogram (ECG): Provides a measurement of heart rate and heart rate variability
  • Thermal feedback: Provides a measurement of skin temperature
  • Galvanic skin response (GSR): Provides a measurement of skin surface moisture

During biofeedback training, patients practice altering internal physiologic processes by using the visual cues that are displayed on the computer screen, in combination with the techniques taught to them by biofeedback professionals. Furthermore, patients are taught various relaxation and coping skills to help them gain control over managing their low back pain symptoms.

Facet Joint InjectionFrom a pharmacological approach to treatment, there are various treatments available for patients suffering from low back pain. One study that examined the treatment of low back pain patients in primary care settings found that non-steroidal anti-inflammatory drugs (NSAIDs) were prescribed to 69% of patients, muscle relaxants were prescribed to 35% of patients, narcotics were prescribed to 12% of patients, and acetaminophen was prescribed to 4% of patients. NSAIDs, including naproxen and ibuprofen, are commonly prescribed to patients with low back pain due to their ability to reduce inflammation, which in turn relieves pain. While NSAIDs are commonly used for pain control, their use is associated with a number of unpleasant side effects including gastrointestinal irritation, bleeding, and ulcers. Ideally, NSAIDs should be recommended to patients for the temporary relief of low back pain and should not be used for prolonged periods of time due to the increased risk of side effects.

Muscle relaxants are often prescribed to patients suffering with low back pain as well. There are two classes of muscle relaxants: antispasmodic and antispasticity. Antispasmodic medications include benzodiazepines and non-benzodiazepines. These medications work to reduce muscle spasm that is frequently seen in patients suffering with low back pain. Antispasticity medications include dantrolene and baclofen. These medications act to reduce the spasticity of the muscles in the affected area.

Antidepressants are also commonly prescribed to patients suffering from low back pain and they have received some empirical support as well. Tricyclic antidepressants have been the most frequently studied class of antidepressants for the treatment of low back pain. This class of medication includes doxepin, amitriptyline, and clomipramine. The exact way that these drugs help to relieve pain is not completely understood; however, it is believed that they block the reuptake of norepinephrine and serotonin within the neuronal synapse.

Two additional classes of antidepressants that are utilized for the treatment of low back pain are selective serotonin reuptake inhibitors (SSRIs), as well as serotonin and norepinephrine reuptake inhibitors (SNRIs). SSRIs include the drugs citalopram, fluoxetine, and fluvoxamine and SNRIs include the drugs duloxetine, venlafaxine, and desyenlafaxine. At times, these drugs are preferred by physicians for the treatment of low back pain because they have fewer side effects than tricyclic antidepressants. The mechanism of action for reducing pain is not known. There has been some research that has shown that they are effective for reducing chronic low back pain; however, whether these pain-relieving benefits are unrelated to the antidepressant effects remains unknown. It is likely that patients suffering with chronic low back pain have also developed accompanying feelings of depression, withdrawal, and hopelessness and the SSRIs and SNRIs may help to relieve these symptoms, which leads to reports of decreased low back pain.

Anticonvulsant medications, including gabapentin, are also used for relieving back pain, particularly neuropathic pain. The mechanism of action of anticonvulsant medications is generally unknown; however, it is believed that these drugs work by increasing the ratio of gamma-aminobutryric acid (GABA) to glutamate. They may also exert their effects due to the effect that they have on the ion channel or by the enhancement of nonsynaptic GABA.

Capsaicin skin patches may provide pain relief for some patients suffering with low back pain, particularly neuropathic pain. Capsaicin is derived from chili peppers and it binds itself to the nociceptors in the skin, thereby exciting the neurons. This results in a period of increased sensory sensitivity to itching, burning, or pricking, followed by a refractory period of reduced sensory sensitivity. After repeated application of the capsaicin patch, the patient can achieve persistent desensitization in the affected area. There is strong support for the effectiveness of capsaicin over the use of placebo treatments in controlled trials.

Individuals suffering from chronic or severe low back pain may be prescribed opioid medications. Opioids include tramadol, codeine, oxycodone, and morphine. These medications are particularly effective for non-specific low back pain that has been unresponsive to other treatments. Opioids exert their pain-relieving effects by binding to the opioid receptors in the brain. There is an abundance of support for the use of opioids for the treatment of short-term pain relief of acute pain. However, there are numerous side effects associated with this type of medication including dizziness, constipation, sweating, and sexual impotence. Further, there is the risk of misuse and abuse of this particular type of medication. It is therefore contraindicated to use this medication for long-term pain relief.

When a patient’s pain is due to problems within the bony structures of the spine, there are various treatments available. A facet joint injection is a nerve block at the facet joint in the spine. For patients suffering with chronic low back pain that is originating within the facet joint, a lumbar facet joint nerve block may be the most effective pain relief option. Additionally, this procedure can be used from a diagnostic standpoint as well as it helps to identify the source of a patient’s pain. Other types of joint injections are available and have shown to be effective for pain relief. These injections include a sacroiliac joint and a trigger point injection. A sacroiliac joint injection is injected into the sacroiliac joint that is located at the base of the spine. On the other hand, a trigger point injection is injected directly into the trigger point that may be irritating spinal ligaments and muscles. These injections typically involve injecting a local anesthetic, combined with a steroid, which helps to numb the area and decrease inflammation. These injections are injected directly into the affected area and are expected to provide almost immediate pain relief.

When a fractured vertebra is the source of a patient’s pain, a vertebroplasty may be beneficial for providing pain relief. The minimally invasive procedure can be performed in an outpatient environment. It involves injecting medical grade acrylic cement into the site of the fractured vertebrae. The acrylic cement dries quickly and creates a support structure within the vertebrae, which eliminates compression caused by the fracture, thereby reducing pain. This is a relatively new procedure; however, it has been shown to provide effective results for relieving low back pain.

For some patients, their low back pain symptoms are the result of spinal surgery. In these patients, low back pain is caused by scar tissue buildup around the spinal nerves in the epidural space after spinal surgery. Adhesiolysis is recommended for these patients as it helps to break up and dissolve scar tissue. During an adhesiolysis procedure, the physician uses a catheter to inject a chemical compound that breaks up the scar tissue that is causing pain. This procedure is usually reserved for patients experiencing low back pain following spinal surgery.

When a damaged intervertebral disc is responsible for a patient’s low back pain, a combination of facet joint injections, epidural steroid injections, and adhesiolysis may be performed. These procedures have received support for their efficacy in providing pain relief due to damaged intervertebral discs.

Rarely, patients do not respond to conservative treatment options or pharmacologic interventions; in these patients other forms of pain management may be needed. Spinal cord stimulation and intrathecal pain pumps are two options that may be recommended to these patients. Spinal cord simulation can help to provide effective pain relief for low back pain that is the result of neuropathy or failed back surgery. For this procedure, a small device is implanted near the spine that delivers electrical impulses to block pain signals. These devices typically come with a handheld device that sends these electrical signals on an as-needed basis. Similarly, intrathecal pump implants are considered for patients with severe, chronic, and non-responsive pain. This procedure involves implanting a device close to the spine, which delivers pain medications directly into the intrathecal or subarachnoid space. Intrathecal pump implants are quite effective for low back pain relief.

Another form of alternative treatment is acupuncture. Acupuncture aims to relieve low back pain by using small needles inserted into specific areas of the body. These areas are determined by where the pain is located, as well as other areas of the body, which may be contributing to a patient’s pain. This form of treatment was developed by ancient Chinese medicine practitioners and is still widely used today. It is regarded as a safe and effective treatment option that carries relatively few risks. The World Health Organization has recognized acupuncture as an effective treatment option for pain conditions. Side effects of acupuncture are limited to minor bruising or bleeding and mild soreness around the area of needle insertion. If electroacupuncture is used, there is also the risk of minor skin irritation. There is some evidence to show that acupuncture helps to increase blood circulation as well as the circulation of other fluids within the affected tissues, which helps to relieve pain, reduce recovery time, and increase muscle strength.

Transcutaneous electrical nerve stimulation (TENS) is another type of alternative therapy for the management of low back pain. This treatment is commonly used in conjunction with acupuncture. TENS therapy delivers electric impulses to peripheral nerves by using electrodes on the surface of the skin. There is evidence to support the use of TENS therapy for the management of low back pain; however, the data is limited and further research is warranted on its efficacy compared to placebo treatments. Currently, the use of TENS on its own for the treatment of pain is not well supported; however, there have been reports of its effectiveness when used in combination with other treatment modalities.

A Botox injection is sometimes recommended for the management of low back pain symptoms. The medication delivered with a Botox injection is a purified botulinum neurotoxin, which is a toxic enzyme produced by the Clostridium botulinum bacteria. This toxin has a paralytic effect of muscles. It is believed that Botox exerts its effects by blocking overactive nerve impulses and inhibiting the release of neurotransmitters that are involved in pain sensation. Findings from research that has been conducted show that patients demonstrated overall improved function compared to placebo controls. For patients with third lumbar transverse process syndrome, there is evidence to support the efficacy of Botox injections that go beyond the effects of traditional acupuncture that is commonly used to treat this condition. Further, patients with mechanical low back pain, which is the result of myofascial pain syndrome, may also report a significant benefit from Botox injections.

Active release technique may be beneficial for patients suffering from low back pain that is not the result of trauma or when there is no active inflammation. Active release technique is a soft tissue modality. For this technique, the practitioner uses their thumb or finger to apply deep pressure to the soft tissue in the affected area. While the pressure is being applied, the patient is instructed to perform various repetitive movements. This pressure, combined with the repetitive movements, causes the muscles to repeatedly elongate and contract. This is believed to restore normal texture of the underlying soft tissues over time. Active release technique can be utilized to help reduce inflammation, stiffness, and pain in low back pain sufferers. This technique may also help to reduce tissue scarring, tearing, and abnormal fusion.

Conclusion

Low back pain is a widespread problem that affects a large percentage of the population; with recent estimates suggesting that up to 84% of adults will suffer from some form of chronic or acute pain and the symptoms vary drastically among patients. However, common complaints of patients with low back pain include muscle cramping and stiffness, muscle spasm, radiating pain, numbness, tingling, and weakness, as well as a sensitivity to touch or pressure. Low back pain can be caused by multiple conditions. Conditions that are often associated with low back pain include disc herniation, osteoarthritis, spinal stenosis, spondylolisthesis, fractured vertebrae, spinal deformities, and spinal infections. There has been a significant amount of research that has found that pain severity and pain perception are two of the most important prognostic factors of long-term outcomes for low back pain patients. This information allows at-risk patients to be identified but also allows for appropriate treatment implementation. Research has shown that a patient’s perception of pain can be altered; however, additional research is needed to clearly identify the relationship between pain perception, pain severity, and individual outcome prediction.

Accurate evaluation of a patient’s low back pain is imperative for successful treatment outcomes. Physicians will likely take a detailed history and perform a focused, but thorough physical exam. During the assessment, serious underlying pathology such as a spinal infection or tumor will be ruled out. There are various treatment options for low back pain that will differ depending on the source of the pain. Treatment options range from non-invasive options such as physical therapy and chiropractic treatment, to more aggressive and invasive options such as spinal stimulation and intrathecal pump implants. Many patients will respond positively to conservative treatment methods; however, there are patients who suffer from unrelenting pain that requires more intensive therapies. Patients should speak with their primary care doctor about any low back pain that they are experiencing in order to accurately diagnose and successfully treat their pain symptoms.

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