What Is Low Back Pain?
Low back pain, also referred to as lumbar spine pain, is a common ailment that is experienced by millions of people in the United States. Recent reports suggest that the majority of adults in the U.S. (84%) will suffer from some type of low back pain during their lifetime. Also of concern is the relapse rate of lower back pain, with reports suggesting that a large percentage (44% to 78%) of individuals who suffer from one occurrence of lower back pain reporting a future pain episode. The CDC reports that lower back pain is associated with significant disability and has a negative impact on both the personal and work life of those who suffer from the condition. Lower back pain also has a significant economic impact in the United States. The National Institutes of Health (NIH) has stated that an estimated 50 billion dollars per year is spent in the United States due to lower back pain.
Lumbar spine pain is a leading cause for individuals missing time from work and is the leading cause of work-related disability. Furthermore, lower back pain is a main cause for decreased work productivity and increased use of medical resources. For these reasons, low back pain has received considerable attention in the research world. Over the past ten years the amount of research investigating prognostic factors that relate to low back pain, and randomized controlled studies testing the various treatment methods that are available to treat low back pain patients, has increased dramatically.
Lumbar spine pain is generally classified as either acute or chronic, depending on the length of time that a patient suffers with the pain. Acute pain is described as short-term pain that typically lasts no longer than three months. Conversely, chronic pain refers to long-term pain that persists for a period of longer than three months. Acute lower back pain episodes can sometimes lead to persistent lower back pain in some patients. Chronic lower back pain generally progresses over time, initially presenting as a dull ache and progressively worsening to severe, unrelenting pain. Chronic lower back pain can lead to significant impairments in an individual’s functioning, often resulting in disability. It has been reported that a significant percentage of the U.S. population (12%) report disability due to their chronic lower back pain symptoms.
Chronic lower back pain that cannot be attributed to a specific cause, including disease, trauma, or tumor is referred to as non-specific lower back pain. There is little evidence that has investigated the prevalence of non-specific, lower back pain. However, some researchers suggest that the incidence rates may be quite high (23%). This statistic suggests that a significant percentage of the population deals with chronic lower back pain every day. Further, several of these patients are unlikely to be able to carry on with their normal work duties due to their significant pain symptoms.
Before beginning treatment for the management of lumbar spine pain, it is important that the physician determines the source of a patient’s pain. The back is a complex structure that consists of a network of tissues, muscles, bones, and nerves that runs from the base of the skull to the pelvis. The vertebral column is a structure that provides support for the body and protection for the fragile spinal cord. Twenty-four individual vertebrae connected to each other make up the fairly flexible vertebral column, as well as nine fused vertebrae, which form the sacrum and coccyx (tailbone).
In between each vertebra are intervertebral discs that provide cushioning and shock absorption and contribute to the overall flexibility of the lumbar spine. Muscles and ligaments connect to the vertebrae of the spine, which provide strength as well as mobility. Inside the vertebral column is the spinal cord, which descends from the brain through the vertebral column to just inferior to the 12th rib in most adults. Each component of the vertebral column is at risk for injury due to disease, wear and tear, or trauma, which can ultimately result in lower back pain.
Lumbar spine pain is characterized by pain or discomfort that originates in the lower back region, specifically from the area inferior to the costal margin and superior to the inferior gluteal folds. Additionally, lower back pain may radiate into the lower extremities. Symptoms of lower back pain vary widely, with some patients reporting a dull, diffuse ache and other reporting a sharp, localized pain. Furthermore, lower back pain symptoms can change overtime with patients reporting episodes of exacerbation of pain. While specific symptoms of low back pain vary among patients, common complaints include muscle spasms and cramping, stiffness, radiating pain into the lower extremities, numbness, tingling, or weakness, as well as an altered sensation to touch.
The work-up of a patient with lower back pain symptoms typically begins with a detailed medical history and focused physical examination. The expectation of the work-up is to determine the cause of a patient’s pain. In some cases, the exact cause of an individual’s pain cannot be determined; in these cases, the practitioner will look to exclude certain ominous diagnoses, including nerve root pain and spinal pathology. Additionally, the practitioner will address certain prognostic factors that are related to lower back pain by inquiring about specific issues related to work, depressed mood, psychosocial distress, pain severity, patient perceptions to pain, previous lower back pain, over-exaggeration of symptom reporting, and degree of impairment. These “yellow flags” help the practitioner develop the most ideal treatment plan and reassessment schedule for each patient.
Moreover, the practitioner will address other areas including patient age (20 years and younger or 55 and older), thoracic pain, pain that is non-mechanical, corticosteroid use, previous cancer, unexplained weight loss, general unwellness, structural changes, and wide-spread neurological discrepancies. These factors are known as “red flags” and may be indicative of serious underlying pathology, including infection, tumor, inflammatory disorders, cauda equina syndrome, or fracture. Patients exhibiting these red flags may not have a serious underlying issue; however, they are at a heightened risk. If a patient presents with multiple red flags, they should be further evaluated.
Causes Of Low Back Pain
Lower back pain may accompany many conditions, including:
- Disc herniation: This is a common cause of lower back pain that is the result of damage or injury to the intervertebral disc. Disc damage can occur with the normal aging process or be the result of acute traumatic event. The damage leads to a weakening of the outer region of the intervertebral disc, which allows the inner region to protrude out. This can cause irritation and inflammation of the surrounding spinal nerves, resulting in pain.
- Osteoarthritis: This is a degenerative condition that results from the breakdown of cartilage. This breakdown can occur because of the aging process, or may occur because of an acute traumatic event. If there is severe damage to the cartilage, bone can begin to rub against bone, which can result in significant pain.
- Spondylolisthesis: This condition occurs when one vertebrae essentially slips off another. A large percentage of patients who have this condition report no related symptoms; it is therefore often classified as non-specific lower back pain. It is estimated that approximately 5% of the population has this structural deformity.
- Spinal stenosis: This condition occurs when there is spinal column narrowing, resulting in spinal canal restriction. Patients with this condition will often report pain relief when leaning forward.
- Spinal (vertebral) fracture: A tremendous force to the spine usually causes this condition.
- Compression fracture: This type of spinal fracture most commonly occurs in women who have gone through menopause, and in patients who have taken corticosteroids for a prolonged period of time. Compression fractures can occur without any extreme force being placed on the vertebrae.
- Spinal deformities: This type of condition refers to genetic issues with the spinal curvature, including scoliosis and kyphosis. Current prevalence rates of these types of spinal deformities are unavailable, however, earlier reports suggest that prevalence rates are quite low, with less than 2% of the population being affected.
- Spinal infections: In rare circumstances, lower back pain may be caused by an infection that has infiltrated into the spinal area. Infection of the spine should be suspected in any patient who presents with lower back pain combined with a fever, as well as in patients who have recently had surgery, those who are immuno-compromised, or those who regularly use drugs.
Various factors have been identified that increase an individual’s risk of suffering from persistent lower back pain, including pain perception, and mental health issues including depression and anxiety, employment status, and gender. A recent five-year long prospective study investigated factors that are prognostic of long-standing outcome in lower back pain patients. The results found that an individual’s severity of pain, as well as their beliefs in regards to persistent pain, was predictive of a poorer outcome at both six-month and five-year follow-ups.
Treatments For Low Back Pain
Throughout the past decade, there has been a significant amount of research conducted on the various treatment options available for lower back pain sufferers. Various treatment methods have undergone extensive testing and have been shown to be beneficial for the treatment of lower back pain. Due to the diversity of conditions that can cause lumbar spine pain, patients are advised to consult with their medical practitioner to establish an effective treatment plan for their specific condition. The medical practitioner can also address any concerns and answer any questions that a patient has regarding their lower back pain symptoms. Additionally, they can also provide educational resources to the patient for further explanation.
For patients who are suffering from mild to moderate lower back pain that is not significantly interfering with their daily functioning, their medical practitioner may recommend that they gradually return to normal activities that they were engaging in prior to their pain episode. Furthermore, their medical practitioner will likely recommend a course of conservative treatment methods, including physical therapy and chiropractic treatment. Research has shown that the majority of patients (90%) who take part in conservative treatment report a significant reduction in their low back pain symptoms.
Chiropractic treatment has been shown to be beneficial for patients suffering from lumbar spine pain and it has also been suggested that it may help to provide improvements in overall health. Chiropractic treatment involves manipulating the spine by either using a high velocity thrust through the joint, which pushes the joint beyond its’ normal range of movement, or by using a low velocity thrust within the joint’s normal range of movement. Side effects of chiropractic manipulation usually occur on the same day of treatment and resolve within 24 to 48 hours following the treatment. These side effects include localized discomfort, headache, fatigue, as well as discomfort in other areas of the body not related to treatment. Serious side effects associated with chiropractic manipulation are rare and include stroke, disc herniation, and cauda equine syndrome. Physical therapy usually involves a combination or manual therapy, including stretching and soft tissue mobilization as well as specific exercises.
Furthermore, the treatment of lumbar spine pain may also focuses on lowering the impairment level and any disability that a patient experiences as the result of their pain symptoms. For example, if a patient is missing time from work due to the lower back pain that they are experiencing, one of their treatment goals may be for them to resume work duties. When a patient experiences disability because of their back pain, they are likely to have an exacerbation of symptoms. That being said, if a patient makes no effort to maintain mobility, they will likely continue to experience significant pain levels.
The disability and pain that is experienced by patients is often the result of somatic pathology. However, there are a multitude of other factors that can contribute to a patient’s level of disability and pain. For example, it’s been shown that the attitudes that a patient has toward pain and disability can have a considerable impact on their pain severity and level of impairment. Additionally, a patient’s psychological distress as well as their response to the beginning of their pain has been shown to have an influence on their condition. In saying this, these issues can become treatment targets. An example of this type of targeted treatment involves utilizing positive reinforcement that rewards positive behaviors and has consequences for bad behaviors.
Additionally, patients may be requested to identify their thoughts and feelings toward their lower back pain and related impairment, as these thoughts may be contributing toward their ongoing pain symptoms. Patients might be requested to identify their thoughts and beliefs regarding their lower back pain, as well as their expectations for managing and controlling their symptoms. It remains unclear if changing a patient’s thoughts and expectations has an impact on pain levels; however, there is some evidence to advocate that these belief changes may have other positive effects for these patients. For example, a changed belief in the nature of pain may inspire a patient to improve their efforts during physical therapy.
Modification of a patient’s physiological response may be necessary. It is widely accepted that stress and tension can have negative effects on a patient’s overall health and well-being. Biofeedback is one form of therapy that has been shown to be beneficial for patients suffering with low back pain by helping them to reduce pain, stress, and tension. This therapy is a non-invasive, non-pharmacological treatment that helps patients recognize their symptoms and teaches them ways to modify their body’s natural response. In order to teach this skill, patients are provided with real-time information regarding their body’s physiologic responses. The specialized biofeedback devices are designed to detect even minute changes in the patient’s physiologic responses and display them on a computer screen for the patient to visualize. The patient is then taught a variety of stress-reducing exercises that help them to effectively alter their response and thereby gain more control over their symptoms.
The most frequently monitored physiological systems in biofeedback therapy include:
- Electromyogram (EMG): This measures muscle tension
- Electroencephalography (EEG): This measures brain wave activity
- Electrocardiogram (ECG): This measures heart rate and heart rate variability
- Galvanic skin response (GSR): This measures the skin surface moisture
- Thermal feedback: This measures skin temperature
During biofeedback training, the patient practices altering their internal physiological processes by utilizing the visual representation of their physiological responses in combination with techniques taught to them by professionals trained in biofeedback. Patients are taught relaxation and coping skills during biofeedback training sessions, which can help to relieve some of their lower back pain symptoms.
A pharmacological approach is often taken for patients suffering with lumbar spine pain. There are a number of drug therapies that are available to these patients, which may be used alone or in combination with other treatment methods. One study investigated the management of lower back pain patients who were seen in a primary care setting. The results showed that the majority (69%) of the patients were prescribed an anti-inflammatory drug (NSAID), followed by muscle relaxants (35%), narcotics (12%), and acetaminophen (4%).
It is believed that many physicians rely on NSAIDs for patients with lower back pain because of their anti-inflammatory properties, which help to decrease inflammation, thereby helping to relieve pain. NSAIDs may provide effective relief, however, there are a variety of side effects associated with their use, including ulcers, gastrointestinal irritation, and bleeding. In general, NSAIDs should be utilized for short-term pain relief; physicians should avoid prescribing NSAIDs for prolonged periods because of a heightened possibility of adverse effects.
Antidepressants are also commonly prescribed to patients suffering with lower back pain. There is some empirical evidence to support the use of this type of medication in this patient population. The most commonly researched class of antidepressant medication has been tricyclics, including amitriptyline, doxepin, and clomipramine. It is believed that these drugs help to relieve lower back pain symptoms by interfering with the reuptake of serotonin and norepinephrine at the synapse of the neuron.
In addition, there are two other classes of antidepressant medications that are now being utilized for the management of lower back pain: serotonin and norepinephrine reuptake inhibitors (also known as SNRIs), including duloxetine, desvenlafaxine, and venlafaxine as well as selective serotonin reuptake inhibitors (also known as SSRIs), including citalopram, fluoxetine, and fluvoxamine. These two classes of drugs are often chosen over tricyclic antidepressants, as there are fewer side effects associated with these two medications. There has been some research investigating SNRIs and SSRIs in relation to their effect on reducing chronic lower back pain. However, it is unclear whether the pain relief benefits are separate from the antidepressant effects of these medications. Oftentimes, patients suffering from chronic pain have accompanying symptoms including feelings of depression, withdrawal, and hopelessness that can all be relieved with SSRIs and SNRIs.
Muscle relaxants are commonly prescribed to patients presenting with lower back pain. This type of medication can be categorized as antispasticity or antispasmodic. Antispasmodic muscle relaxants, including non-benzodiazepines and benzodiazepines, work by reducing muscle spasm that is commonly associated with lower back pain. On the other hand, antispasticity medication, including baclofen and dantrolene, works by reducing muscle spasticity.
There is some empirical evidence to support the use of these medications to provide short-term relief of lower back pain. Certain anticonvulsant medications, including gabapentin, are commonly used to reduce low back pain, particularly neuropathic pain. The mechanism of action of these medications remains relatively unknown; however, it is thought that these drugs have the ability to increase the proportion of gamma-aminobutyric acid (GABA) compared to glutamate. Additionally, they may provide pain relief due to the nonsynaptic GABA enhancement or their ion-channel effect.
A capsaicin skin patch is another type of pharmacological approach that is sometimes used for the relief of lower back pain symptoms, particularly for neuropathic pain. Capsaicin is derived from chili peppers and it binds to the skin nociceptors, which results in neuronal excitement. The initial reactions to capsaicin patches include itching, burning, or pricking, and subsequently a period of decreased sensation sensitivity. After repeated application of the patches, the patient becomes desensitized in the area where the patch was applied. There is sufficient evidence from controlled trial that support the efficacy of capsaicin patches over placebo treatments.
Patients who suffer from severe, debilitating pain may require a stronger type of medication for pain management. If the patient fails to respond to other treatment options including conservative therapies and over-the-counter pain and anti-inflammatory medication, the physician may prescribe opioids. Opioid medications include codeine, tramadol, morphine, and oxycodone. Opioids are particularly effective for the management of persistent, non-specific lower back pain.
Opioids work by attaching to the brain’s opioid receptors. There is a considerable amount of evidence that supports opioid use for the temporary relief of acute, severe pain. However, prolonged use of opioids is associated with a number of side effects including constipation, sweating, dizziness, and sexual impotence. Additionally, there are concerns in regards to patient abuse and misuse of opioids. Therefore prolonged use of this type of medication for lower back pain management is not recommended.
When lower back pain results from issues with the structures that make up the spinal column, there are various treatment methods available, including facet joint injections, sacroiliac joint injections, and trigger point injections. A facet joint nerve root block is a procedure that blocks the nerve root at the facet joint. Usually an anesthetic combined with a steroid is injected into the facet joint to provide pain relief.
Research has shown that lumbar facet joint injections are the most efficacious treatment option for patients who suffer from chronic lower back pain that stems from within the facet joint. This technique is also often used for diagnostic purposes as it provides physicians with information regarding the origin of a patient’s pain. Sacroiliac injections are administered into the sacroiliac joint, which is found bilaterally, at the bottom of the spine. Trigger point injections are injected directly into the trigger point and usually results in almost immediate pain relief. Trigger point injections are proven to be very effective for the management of lower back pain.
When a patient’s chronic lower back pain is caused by a vertebral fracture, a vertebroplasty is often recommended. This procedure can be performed in an outpatient clinic and involves injecting an acrylic cement into the region of the vertebral fracture. Once the cement is dried, it helps to create a supportive area within the affected vertebra that can eliminate compression that the fracture was causing. This technique is quite new, but has been found to be very efficacious for reducing pain in the lower back.
Occasionally patients experience low back pain following spinal surgery. The pain that these patient’s experience is due to a buildup of scar tissue in the epidural space encasing the spinal nerves. Adhesioloysis is recommended for these individuals. During this procedure, a catheter is inserted to deliver a drug that helps to dissolve the buildup of scar tissue. This type of treatment is most commonly used on patients suffering from back pain after surgery. A recent study investigating this procedure found that it produces effective results.
When lower back pain results due to intervertebral disc damage, a combination of steroid injections into the epidural space, adhesiolysis, and facet joint injections may be used to help reduce pain. These procedures have been shown to be effective for relieving lower back pain that is due to damaged intervertebral discs.
In rare cases, a patient’s lower back pain symptoms are unresponsive to oral medications and injections directly into the affected spinal nerves. In these patients, alternative pain management strategies may be necessary. Stimulation of the spinal cord is one procedure that may help to relieve pain for patients who have persistent, unresponsive lower back pain that is caused by failed spinal surgery or neuropathy. Spinal cord stimulation involves implantation of a small device close to the spine. This implanted device delivers electric impulses that act to block pain signals. These devices usually consist of a remote that the patient can control, which sends the electrical impulses on an as-needed basis.
Another similar type of treatment is an intrathecal pump implant. These devices are considered for patients suffering from chronic, severe lower back pain that is unresponsive to other types of pain management therapies. An intrathecal pump implant procedure involves implantation of a medical device near the spine, which facilitates the delivery of pain medication straight to where it is needed, the spinal cord. These devices are especially effective for lower back pain because pain medication is directly sent into the subarachnoid space or intrathecal space.
In addition to conventional medical management of lower back pain, there are numerous alternative treatment options available for pain management. Acupuncture is one type of treatment that aims to reduce lower back pain by inserting small needles into specific areas of the body. These specific points are referred to as acupuncture points and typically involve placement around the site of pain, in addition to distant sites that may be adding to a patient’s pain. Chinese medical practitioners were responsible for developing this alternative treatment, and it is currently regarded as a safe, alternative treatment for the management of lower back pain.
Side effects of acupuncture treatment include mild discomfort and slight bruising or bleeding at the needle placement site. If the practitioner chooses to use electroacupuncture, the patient may experience slight skin irritation around the area of needle placement. There is some evidence to suggest that acupuncture helps to improve the flow of blood and various fluids within the affected area, which helps to reduce pain and recovery time, and improve muscle strength. The World Health Organization (WHO) has stated that acupuncture is an effective pain management therapy.
Transcutaneous electrical nerve therapy (TENS) is another non-invasive treatment option that can be utilized for the management of lower back pain. TENS therapy is often used in combination with acupuncture. When using a TENS machine, the practitioner places electrodes on the skin’s surface. These electrodes deliver electrical impulses to peripheral nerves. The use of TENS therapy as a stand-alone treatment for pain management is not widely supported by the medical community. However, it can be effective when used in combination with other pain control therapies that aim to reduce the degree of disability in low back pain patients. There is some evidence to support the use of TENS therapy for the management of low back pain; however, the evidence is limited and more research is needed to examine the effectiveness of TENS therapy above placebo treatments in patients suffering from low back pain.
Botox injections are another therapeutic option for the management of lower back pain symptoms. Botox is derived from the Clostridium botulinum toxin and has a paralyzing effect on muscle tissue. Botox injections are thought to relieve lower back pain by blocking the overactive nerve impulses and by inhibiting the release of acetylcholine, which is a neurotransmitter that is involved in pain sensation. There are numerous randomized, controlled trials that have investigated the efficacy of Botox injections. The findings of these trials suggest that patients experienced pain relief at a three-week follow-up, which further improved at an eight-week follow-up. Additionally, patients demonstrated an overall improvement in functioning compared to control patients who received placebo treatments. In particular, for patients with third lumbar transverse syndrome, evidence supported the effectiveness of Botox injections that were greater than traditional acupuncture treatment. Furthermore, patients suffering from mechanical low back pain secondary to bilateral myofascial pain syndrome also reported significant reductions after Botox injections.
Patients who have low back pain unrelated to acute trauma or those who have no inflammation may benefit from a therapy called active release technique. The practitioner uses their thumb or finger to apply deep pressure to the tissues around the area that is affected. The doctor then asks the patient to perform various movements while the pressure is being applied. This results in repeated contraction and elongation of the muscles, which supposedly restores the underlying soft tissues. Active release technique helps to reduce muscle inflammation, stiffness, and pain. This technique is also thought to help reduce the occurrence of abnormal fusion, scar tissue formation, and tearing.
A common ailment that affects different aspects of the vertebral column is lumbar spine pain. It is estimated that the majority of adults will likely suffer from lower back pain at some type during their lifetime. Lower back pain is generally classified as either chronic or acute in nature, depending on the duration of pain symptoms. There are a variety of different conditions that can lead to low back pain, including disc herniation, spondylolisthesis, osteoarthritis, fractured vertebrae, spinal stenosis, spinal deformities, and spinal infections. Other symptoms that patients with low back pain commonly complain about are stiffness, cramping, muscle spasm, numbness, weakness, tingling, altered sensation, and radiating pain.
A significant amount of research has supported the fact that pain severity and pain perception are two of the most valuable factors for predicting long-standing outcomes. This can be beneficial for identifying patients who are likely to suffer ongoing difficulties and may also be helpful in developing optimal treatment plans. For example, a physician can identify an at-risk patient and give them a patient-centered treatment plan.
Accurate assessment and diagnosis of lumbar spine pain is vital for successful treatment outcomes. A detailed history and physical exam will help the physician arrive at an accurate diagnosis of a patient’s low back pain. They will rule out serious underlying pathology including tumor and spinal infection before proceeding with a treatment plan for management of the patient’s symptoms. A variety of effective conservative treatment options are available for patients suffering with lower back pain including analgesic and anti-inflammatory medications, chiropractic care, and physical therapy. More invasive options include simulation of the spinal cord, intrathecal pump implants, and injections into the facet joints, sacroiliac joints, and trigger points. These are available for patients with severe, chronic lower back pain that has not responded to conservative management. Patients suffering from lower back pain symptoms should speak to their physicians about potential pain management strategies.
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