LOW BACK PAIN (LBP)

• ACRONYMS

• ACP - American College of Physicians
• ACR - American College of Radiology
• APS - American Pain Society
• LBP - Low back pain
• MRI - Magnetic resonance imaging
• NSAID - Nonsteroidal anti-inflammatory drugs
• PT - Physical therapy
• RCT - Randomized controlled trial
• RD - Radiofrequency denervation
• TENS - Transcutaneous electrical nerve stimulation

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• OVERVIEW

• Low back pain is one of the most common complaints seen in primary care. Depending on the study, up to 84% of people experience low back pain at some point in their lives. Chronic low back is present in about 23% of the population. In 2016, LBP and neck pain accounted for an estimated $134.5 billion dollars of healthcare spending making spine disorders the number one healthcare expenditure in the U.S.
• Given its high prevalence, it's not surprising that a vast array of modalities are marketed for its treatment. The majority of these therapies have marginal-to-no benefit. [1,75]

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• TERMS AND DEFINITIONS

• Cervical spine
• Cervical spine refers to the seven vertebrae at the upper end of the spine
• The cervical vertebrae start just below the skull and end at the thoracic vertebrae
• The seven cervical vertebrae are often referred to individually as "C-one, C-two, etc."
• Diseases of the cervical vertebrae will typically cause neck and arm pain
• Spine overview - overview of entire spine

• Disc protrusion
• Disc protrusion (also referred to as "bulging disc" "slipped disc" and "herniated disc") occurs when the cartilage disc bulges out from underneath a vertebra towards the spinal cord
• Protruding discs may touch or encroach on the spinal cord (sometimes producing pain), or they may not
• Disc protrusion can occur to one side of the disc or it may be "broad-based" meaning the entire face of the disc protrudes
• Disc Protrusion - illustration of disc protrusion

• Disc extrusion
• Disc extrusion (also referred to as a ruptured disc) occurs when the annulus fibrosus tears open and the gel-like nucleus pulposus extrudes toward the spinal cord
• Disc Extrusion - illustration of disc extrusion

• Disc sequestration
• Disc sequestration occurs when a portion of the gel-like nucleus pulposus extrudes and then separates from the main disc
• Disc Sequestration - illustration of disc sequestration

• Lumbar spine
• Lumbar spine refers to the five vertebrae at the lower end of the spine
• The lumbar vertebrae are located between the thoracic vertebrae (above) and the sacrum (below)
• The five lumbar vertebrae are often referred to individually as "L-one, L-two, etc."
• Lower back pain typically involves the lumbar vertebrae
• Spine overview - overview of entire spine

• Radiculopathy
• Radiculopathy is a general term for pain caused by compression of a nerve root as it leaves the spinal cord. Nerve compression may occur from a herniated disc or bony malformations of the vertebra. Symptoms of radiculopathy include pain and/or weakness in the distribution of the affected nerve (see sciatica below).

• Sacrum
• The sacrum is the bony structure at the bottom of the spine
• The last lumbar vertebra (L5) connects to the sacrum
• The sacrum forms the rear part of the pelvis
• Spine overview - overview of entire spine

• Schmorl's node or nodule
• Schmorl's node is a finding often described on radiological studies of the spine
• It is an area where the intervertebral disc has herniated up into the vertebral body (as opposed to out from under the vertebral body)
• Schmorl's nodules are common, and have been found in up to 70% of the population in some studies
• The relevance of Schmorl's nodes and their association, if any, with back pain is unknown [65]

• Sciatica
• The sciatic nerve is a large nerve that exits the lower spine on each side of the body and runs down the back of the legs to the feet. The sciatic nerve originates from the L4 - S3 nerve roots, and it contains both sensory and motor fibers.
• Herniated discs in the lower spine can press on the roots of the nerve and cause it to become inflamed, a condition called sciatica. Symptoms of sciatica include pain, weakness, tingling, and/or numbness in the distribution of the affected nerve (see below). Sciatica can be treated with surgery or conservative measures (see disc disease treatment for more).
• L4 nerve - the hip, thigh, inner knee, and calf
• L5 nerve - buttocks, outer thigh, anterior calf, and top of foot
• S1 nerve - buttocks, posterior leg and calf, and side of foot

• Spondylolysis
• Each vertebrae has four joints - two joints with the vertebra above it, and two joints with the vertebra below it
• The bone that connects the upper and lower joint on each side is called the pars interarticularis
• In some people, this bone forms a stress fracture
• A stress fracture in the pars interarticularis is referred to as spondylolysis
• Spondylolysis figure - illustration of spondylolysis
• Spondylolysis - review of spondylolysis

• Spondylosis
• Spondylosis (also referred to as "spinal osteoarthritis" and "degenerative changes") is a general term for degenerative changes of the discs and vertebral bodies in the spine that occur with age
• When the cartilage discs are involved, it can result in narrowing of the space between two vertebral bodies
• When the bony vertebral bodies are involved, it can result in osteophytes or bone spurs that stick out

• Spondylolisthesis
• Spondylolisthesis is a condition where one vertebral body is displaced forward in relation to the one below it
• Spondylolisthesis may result from spondylolysis, and it may lead to spinal stenosis
• Spondylolisthesis figure - illustration of spondylolisthesis
• Spondylolisthesis - review of spondylolisthesis

• Spondylitis (spondylopathy)
• Spondylitis (also referred to as spondylopathy) to as is a general term that means inflammation of a vertebral body
• Spondylitis can result from infections or diseases (e.g. ankylosing spondylitis)

• Thoracic spine
• Thoracic spine refers to the twelve vertebrae that are found between the cervical spine (above) and the lumbar spine (below)
• The twelve thoracic vertebrae are often referred to individually as "T-one, T-two, etc."
• The ribs connect to the thoracic vertebrae in the back
• Spine overview - overview of entire spine

• Vertebra and disc
• The spine is formed by bony vertebra and cartilage discs
• The vertebra consists of a solid round body with extensions in the back that form a circular ring
• The spinal cord runs through the circular ring
• Cartilage discs sit in-between each vertebral body
• The discs provide cushioning and allow flexibility and motion in the spine
• Vertebra and disc - illustration of the vertebra and disc

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• TYPES OF LBP

• Reference [4]

Prevalence of LBP Causes Seen in Primary Care
Etiology of LBP	Prevalence
Nonspecific LBP	70%
Age-related degenerative changes of the spine	10%
Disc disease	4%
Compression fracture	4%
Spinal stenosis	3%
Spondylolisthesis	2%
Cancer	0.7%
Inflammatory arthritis (ankylosing spondylitis, etc.)	0.3%
All other	6%

• Nonspecific LBP (70 - 80% of LBP cases)
• Overview
• Also referred to as "musculoskeletal back pain" "mechanical low back pain" and "lumbar strain"
• Nonspecific LBP is by far the most common cause of LBP
• Pathology
• Nonspecific low back pain is defined as low back pain where no identifiable cause (ex. fracture, slipped disc) for the pain can be found
• Symptoms
• Symptoms of nonspecific low back pain include a general aching across the lower back that may be worsened by prolonged standing and/or physical activity
• Risk factors
• In studies, the association between nonspecific low back pain and possible risk factors has been inconsistent. Factors that may increase the risk for nonspecific low back pain include the following:
• Family history
• Obesity
• Occupational factors (work-related lifting, carrying, pushing, pulling, walking, standing, etc.)
• Psychological factors
• Physical activity
• Smoking [1,5-16]
• Treatment
• See treatment of nonspecific LBP below

• Disc disease (4% of LBP cases)
• Overview
• Disc disease is also referred to as "herniated disc" "slipped disc" "ruptured disc" and "bulging disc"
• Pathology
• Disc disease occurs when one of the cartilage discs in the lumbar spine herniates or protrudes out from under a vertebra toward the spinal cord (see disc protrusion illustration and disc extrusion illustration)
• If the protruding disc pushes on the spinal cord or on a nerve leaving the spinal cord, it may cause pain and weakness in the nerve's distribution
• Symptoms
• Symptoms of disc disease include pain that radiates across the buttocks and down a leg (sciatica). Weakness in the affected leg may also occur.
• The pain from disc disease may occur suddenly or it may be gradual
• Risk factors
• In studies, the association of disc disease with possible risk factors (e.g. obesity, physical activity) has been inconsistent. No well-defined risk factor has been identified. [17]
• Treatment
• See disc disease treatment below

• Spinal stenosis (3% of LBP cases)
• Pathology
• Spinal stenosis occurs when the spinal canal in the lumbar region narrows
• Since narrowing tends to occur with aging, spinal stenosis is typically seen in older patients (> 60 years old)
• Spinal stenosis - illustration of spinal stenosis
• Narrowing of the canal can occur for a number of reasons including:
• Disc disease
• Thickening of the ligaments that run along the spinal canal (thickened ligamentum flavum)
• Arthritic changes of the bones and joints in the spine
• Spondylolisthesis
• Symptoms
• Symptoms of spinal stenosis include pain that radiates across the buttocks and into the thigh and lower legs
• The pain may be worsened by prolonged walking or standing and relieved when leaning over or sitting [3]
• Risk factors
• Advanced age - Age > 60 years is the most important risk factor for spinal stenosis
• History of chronic steroid use
• Paget's disease
• History of disc or spine disorders (ex. disc disease, spondylolisthesis) [3]
• Treatment
• See spinal stenosis treatment below

• Compression fracture (4% of LBP cases)
• Pathology
• Vertebral compression fractures occur when a vertebra collapses on itself
• The fracture is typically related to acute trauma that may be mild (sneezing, lifting a trivial object, etc.)
• Most common vertebra affected are T8-T12, L1, and L4
• Compression fractures - illustration of vertebral compression fractures
• Symptoms
• Back pain from vertebral compression fractures may be acute, occurring suddenly with the fracture, or it may develop slowly
• Fractures may lead to kyphosis (a hunched-over posture) and loss of height
• Risk factors
• Advanced age - Age > 65 years for men, and > 75 years for women
• Females
• History of chronic steroid use
• Osteoporosis
• Trauma
• Very thin or frail
• White or Asian race [18]
• Treatment
• See vertebral compression fracture treatment below

• Other causes of LBP
• Cancer
• Cancer may present as back pain in a very small number of patients
• Risk factors include a history of cancer, back pain accompanied by unexplained weight loss, and advanced age
• Infection
• Infections of the spine may present as low back pain
• Risk factors include history of IV drug abuse, recent bacterial infection, and fever
• Cauda equina syndrome
• Cauda equina syndrome is a rare condition that involves severe compression of the nerves in the lower spine
• Causes of cauda equina syndrome include tumors of the lower spine and massive midline disc herniation
• Symptoms of cauda equina syndrome include inability to urinate, inability to control bowel movements, loss of sensation around the rectum, and leg weakness [4]
• Ankylosing spondylitis
• Ankylosing spondylitis is a rheumatological disorder that causes inflammation and overgrowth of the vertebra in the spine
• It is associated with a gene called HLA B27 (present in 90-95% of affected patients)
• Ankylosing spondylitis typically presents in younger patients (< 30 years old), and it is more common in men (2:1 ratio)
• Bony growth within spinal ligaments (syndesmophytes) and inflammation of the sacroiliac joint (sacroiliitis) are common features seen on X-rays [2]
• See features of different arthritis syndromes for more
• Symptoms include:
• Morning stiffness and LBP that is improved with exercise but not with rest
• Restriction of motion in the lower back
• Restriction of chest expansion

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• DIAGNOSIS

• Overview
• The American College of Physicians and The American Pain Society issued a set of guidelines that is helpful in diagnosing the cause of LBP
• The steps below incorporate their guidelines into a process for diagnosing LBP

Steps to Determining the Cause of LBP
STEP 1 - Categorize LBP into 1 of 3 categories Nonspecific LBP Disc Disease and spinal stenosis Other causes [20]
STEP 2 - Evaluate for disc disease Symptoms Symptoms of disc disease include pain that radiates across the buttocks and down a leg (sciatica). Weakness in the affected leg may also occur. The pain from disc disease may occur suddenly or it may be gradual Physical exam Disc disease may be obvious in some cases, and it may be difficult to detect in others A number of physical exam findings can be used to help determine if disc disease is present The utility of these findings is discussed below - see physical exam tests for disc disease
STEP 3 - If disc disease is suspected, evaluate for spinal stenosis Risks The most important risk factor for spinal stenosis is advanced age (> 60 years old) In younger patients, spinal stenosis will be much less likely Symptoms and physical exam A review in the JAMA evaluated the accuracy of physical exam findings and symptoms in predicting spinal stenosis The review looked at studies where exam findings and symptoms were compared to definitive measures (CT, MRI, etc.) The following findings were most helpful: Neurogenic claudication (pain with walking or standing that is relieved when bending forward) - sensitivity 82%, specificity 78% Absence of pain when seated - sensitivity 47%, specificity 94% Wide-based gait (walking with feet spread apart) - sensitivity 42%, specificity 97%
STEP 4 - In certain patients, consider other causes of back pain Elderly, frail patients with osteoporosis - consider vertebral compression fractures Cancer history - consider cancer recurrence or metastasis to the spine Younger patients with decreased range of motion and stiffness - consider ankylosing spondylitis Bowel and bladder symptoms - consider cauda equina syndrome Fever and/or IV drug user - consider infection

• Physical exam tests for disc disease
• Straight leg raise (SLR)
• The SLR is probably the most common test performed in patients presenting with LBP. During the SLR, the patient lies flat on their back with their legs extended straight. The examiner then raises each straightened leg one at a time. Raising the straightened leg stretches the sciatic nerve. If the sciatic nerve is inflamed from disc disease in the lower back, then stretching the nerve may elicit pain in the raised leg (not the back)
• A variation of the SLR test called "Lasegue's test" involves lowering the leg slightly (5-10°) from the fully-raised position, and then pulling the end of the foot towards the shin (dorsiflexion). This supposedly stretches the sciatic nerve more than the SLR.
• A Cochrane meta-analysis evaluated the accuracy of the SLR test in predicting disc disease by looking at studies where exam findings were compared to definitive measures (MRIs, CT scans, findings at surgery). The SLR test had a sensitivity of 92% and a specificity of 28%. This means a negative test makes the disease unlikely, but a positive test is not very helpful [21]
• Crossed straight leg raise (CSLR)
• The CSLR test is performed exactly like the SLR test (see above), except that the test is considered positive when pain occurs in the leg opposite the one being raised
• A Cochrane meta-analysis evaluated the accuracy of the CSLR test in predicting disc disease by looking at studies where exam findings were compared to definitive measures (MRIs, CT scans, findings at surgery). The CSLR test had a sensitivity of 28%, and a specificity of 90%. This means a positive test makes the disease likely, but a negative test is not very helpful [21]
• Other tests
• Muscle weakness
• Lower extremity reflexes
• Sensory deficits in the legs and feet
• Slump test - In the slump test, the patient sits bent forward in a chair with legs outstretched and toes pointing up The examiner then slowly eases the patient forward to increase stretch on the sciatic nerve
• Bell test - In the bell test, the examiner applies pressure with the thumb between the L4/L5 or L5/S1 spinous process. The test is positive if the pressure reproduces the leg pain the patient is experiencing. [21]

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• IMAGING STUDIES

• Indications for imaging
• Overview
• Physicians vary greatly in what studies, if any, they will order in patients with LBP
• Clinical studies have consistently found that in the majority of people, radiological studies do not affect outcomes and are unnecessary. Despite this, a large number of patients with LBP still undergo X-rays, MRIs, and CT scans.
• Overuse of radiological studies in LBP is a significant contributor to unnecessary healthcare costs
• Several professional organizations have issued guidelines for ordering radiological studies in patients with LBP. Guidelines from the ACP and APS are listed below along with guidelines from the ACR. The ACR guidelines list a number of "red flags" that they say may indicate a serious underlying disease is present. The utility of "red flags" was evaluated in one study (see red flag study), and they were generally not found to be useful. Another study looked at the impact of early imaging on outcomes. It is also summarized below (see early imaging study)

• ACP and APS recommendations for imaging in LBP
• Clinicians should not routinely order radiological studies for nonspecific low back pain
• Clinicians should order radiological studies when severe or progressive neurological deficits are present or when serious underlying conditions are suspected
• Clinicians should order an MRI (preferred) or CT scan in patients with persistent ( > 4 weeks) low back pain and signs and symptoms of disc disease only if they are potential candidates for surgery or epidural spinal injections [20]
• ACR "red flag" findings in LBP that may indicate a serious underlying condition
• 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
• Prolonged use of steroids
• Acute onset of urinary retention or overflow incontinence
• Loss of anal sphincter tone or fecal incontinence
• Saddle anesthesia
• Global or progressive motor weakness in the lower limbs
• Prior back surgery [24]

• STUDY
  Red flag findings and their association with serious spine pathology, Arthritis and Rheumatism (2009) [PubMed abstract]
• A study in Arthritis and Rheumatism enrolled 1172 patients who presented to a primary care provider with LBP
• Patients were given a questionnaire that contained 25 red flag questions at their initial visit
• Patients were then followed for a year to see if they developed a serious diagnosis for their LBP
• Serious diagnoses were defined as vertebral fracture, cancer, infection, cauda equina syndrome, and inflammatory arthritis
• At the end of the study, the following results were seen:
• Only 11 patients (0.9%) were diagnosed with a serious condition (8 were vertebral fractures)
• 80% of patients had at least one red flag, and the median number of red flags per patient was two [25]

• STUDY
  Association of early imaging for back pain with clinical outcomes in older adults, JAMA (2015) [PubMed abstract]
• A cohort study in the JAMA compared outcomes between older patients (≥ 65 years old) who received imaging (X-ray, CT, MRI) within 6 weeks of presenting to a physician with LBP to those who did not (control group)
• The primary outcome was back or leg pain-related disability measured by the modified Roland-Morris Disability Questionnaire 12 months after enrollment
• After 12 months, the following was seen:
• Among 5239 patients, 1174 had early X-ray, and 349 had early MRI or CT
• There was no significant difference between the early imaging group and the control group for the primary outcome [66]

• X-ray
• X-rays only show the bones of the spine. They do not show the discs or spinal cord.
• X-rays are useful for evaluating the following:
• Degenerative changes of the vertebra
• Spondylolysis/spondylolisthesis
• Vertebral compression fractures
• Changes in ankylosing spondylitis

• MRI
• MRI is the preferred study for visualizing problems involving the discs and spinal cord
• MRI scans show the spinal cord, bones, and discs, and they do not expose the patient to ionizing radiation
• MRIs are useful for evaluating the following:
• Disc disease
• Spinal stenosis
• Vertebral compression fractures
• Spondylolysis/spondylolisthesis
• Infections

• MRI findings in patients without LBP
• One of the well-documented quandaries of imaging patients with LBP is that many of the abnormalities that cause LBP (ex. herniated discs, spinal stenosis, etc.) are found in people without LBP
• When abnormalities are seen, the question then arises as to whether the finding is actually responsible for the patient's symptoms or is merely incidental
• A number of studies have looked at the frequency of abnormalities on MRIs in patients without LBP. Findings from two studies are presented in the tables below.

• Reference [22]

MRI findings in 98 people (average age 42 years) with no LBP
MRI finding	% of people
Disc bulge	52%
Disc protrusion	27%
Schmorl's nodule	19%
Disc extrusion	1%

• Natural course of disc disease
• Disc disease (protrusions, extrusions, herniations, sequestrations, etc.) will improve or resolve in most patients without intervention
• The table below shows the natural course of disc disease in 154 patients (average age 45 years) with sciatica who were followed for 14 months. In 90% of patients, MRI findings matched symptoms (10% of patients had no disc disease or nerve root compromise and were excluded from the follow-up). All included patients were treated conservatively (no surgery).
• Disc disease was divided into the following categories:
• Bulging disc - disc tissue extends beyond > 50% of vertebral body's outer rim
• Broad-based disc protrusions - herniation of 25 - 50% of disc circumference
• Focal disc protrusions - herniation of < 25% of disc circumference
• Disc extrusions
• Disc sequestrations

• CT scan (CAT scan)
• CT scans allow visualization of the spinal cord and discs
• Images of bone (vertebral bodies) are superior to MRI, but images of discs and spinal cord are inferior to MRI
• CT scans are cheaper and more widely available than MRIs
• CT scans expose patients to ionizing radiation
• CT scans are useful for evaluating the following:
• Disc disease - inferior to MRI
• Spinal stenosis
• Vertebral compression fractures
• Spondylolysis/spondylolisthesis

• CT myelogram
• CT myelogram is a type of CT scan where contrast is infused around the spinal cord to improve the images of the discs and spinal cord
• CT myelogram is typically performed when metallic hardware is present in the spine from a previous spinal fusion, because the hardware will distort the images on an MRI scan

• Nerve conduction studies (NCS) and electromyography (EMG)
• NCS and EMG are studies that measure nerve and muscle activity in the arms and legs
• On rare occasions, they may be performed to detect nerve and muscle changes from disc disease

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• PROGNOSIS

• Nonspecific LBP
• The majority of people with an acute episode of nonspecific LBP will improve within a few weeks to several months [1,4]
• Recurrent episodes of nonspecific LBP are common (about 73% of patients within 1 year) [26]
• A small percentage of patients will go on to develop chronic LBP (10 - 15%) [1]
• Factors associated with continued pain and/or disability
• Worrying and health anxiety
• Claims for compensation/disability
• Minimal or no exercise in leisure time
• More intense pain
• Longer duration of pain
• Fear avoidance of physical activity
• Do not think will be able to return to work [27]

• Disc disease
• The majority of people who experience symptoms of disc disease (sciatica) will recover in 3 - 5 months
• In one review, 60% of patients with disc disease had a marked decrease in leg and back pain by 2 months. At one year, 20 - 30% of patients still had back and/or leg pain. [30]
• In another study, 36% of patients with sciatica showed major improvement in 2 weeks, and 73% showed reasonable to major improvement after 12 weeks. [29]

• Spinal stenosis
• A study in the journal Spine followed 49 patients with spinal stenosis for 3 years. Patients were given aggressive nonsurgical treatment (steroids injections, physical therapy, medications)
• After an average follow-up of 33 month, the following was seen:
• Nine patients (18%) received surgery because they did not improve. Of these patients, 78% had severe stenosis on MRI versus 38% in the group that did not receive surgery.
• In patients who did not receive surgery, 65% had improvement in their pain, 18% were worse, 17% were the same. For functional outcomes, 40% had improvement, 25% were worse, 35% were the same [34]

• Vertebral compression fractures
• Vertebral compression fractures typically cause acute back pain that improves over a period of 3 months
• A fraction of patients (up to 40% in one study) will go on to develop chronic pain [37]
• Vertebral compression fractures can lead to kyphosis in some patients

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• TREATMENT | Nonspecific LBP

• Overview
• The main treatment for nonspecific LBP is medications and/or some type of physical therapy or exercise
• In trials, the benefits of structured physical therapy have been null to marginal. A trial that compared physical therapy to usual care in patients with acute LBP is presented below along with a meta-analysis of PT trials,

• STUDY
  Exercise Therapy for Nonspecific Low Back Pain: a Meta-Analysis, Annals of Internal Medicine (2005) [PubMed abstract]
• A meta-analysis in the Annals of Internal Medicine evaluated trials where exercise therapy was compared to no therapy or other therapy in nonspecific LBP
• The study found the following results:
• In acute LBP (pain < 6 weeks), exercise therapy was not significantly better than other therapies
• In subacute LBP (pain 6-12 weeks), exercise therapy was not significantly better than other therapies
• In chronic LBP (pain > 12 weeks), exercise therapy was significantly better than no exercise or other therapies
• Exercise therapy typically includes trunk/core strengthening exercises [28]

• Summary
• The study detailed above found that PT offered a marginal benefit in LBP disability at 3 months and less. The benefit failed to meet the prespecified clinically important margin of difference. Given the fact that studies involving PT are inherently unblinded, it's likely that early PT offers no real benefit in LBP.
• Results from the meta-analysis are consistent with the fact that a large number of people with nonspecific LBP improve within several months regardless of treatment
• Early PT should be avoided in most patients. Patients with chronic LBP (> 12 weeks) should focus on exercises that strengthen their core as this will likely help alleviate and prevent their pain over time (see low back pain workout for more).

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• TREATMENT | Disc disease

• Overview
• The two main treatments for disc disease are conservative therapy and surgery. Conservative therapy may include physical therapy, oral medications (e.g. NSAIDs, opiates), and spinal injections.
• Three trials that compared surgery to conservative treatment are detailed below, along with a study comparing epidural injections to sham injections

• STUDY
  Microdiskectomy vs Conservative Treatment for Sciatica Lasting 4 - 12 Months, NEJM (2020) [PubMed abstract]
• Design: Randomized controlled trial (N=128 | length = 6 months) in patients with unilateral radiculopathy for 4 to 12 months and findings on MRI of posterolateral herniation of the disk between L4 and L5 or L5 and S1 on the appropriate side, with compression of the corresponding nerve root
• Treatment: Microdiskectomy vs Conservative treatment for a minimum of 6 months
• Primary outcome: Leg pain intensity score on the visual analogue scale (ranging from 0 to 10, with higher scores indicating a greater intensity of pain) at 6 months after randomization
• Results:
• Baseline leg pain intensity score: Microdiskectomy - 7.7, Conservative therapy - 8.0
• Primary outcome: Microdiskectomy - 2.8, Conservative therapy - 5.2 (p<0.001)
• In the Microdiskectomy group, 12.5% of patients did not receive surgery. In the Conservative therapy group, 97% of patients were continuing to receive nonsurgical care at 6 months.
• Findings: In this single-center trial involving patients with sciatica lasting more than 4 months and caused by lumbar disk herniation, microdiskectomy was superior to nonsurgical care with respect to pain intensity at 6 months of follow-up.

• Summary
• The three studies above comparing surgery to conservative therapy are all limited by the fact that treatment was unblinded, which means the placebo effect was in full force. Two of the trials also had high crossover rates, which biases the results toward the null in intention-to-treat analysis. Until a well-done trial comparing surgery to sham surgery is performed, it remains unclear what the overall benefits (if any) of surgery for disc disease are.
• The epidural injection study found no benefit of injections when compared to sham injections. Another study detailed below (see anticonvulsants) found no benefit of injections when compared to gabapentin. Any effect seen with spinal steroid injections may be secondary to systemic absorption of the steroid and not placement. A recent study of steroid injections in spinal stenosis found suppressed cortisol levels in patients receiving steroid injections (see spinal stenosis injections). This finding supports a systemic effect.
• Symptoms of disc disease are very painful and can be frightening to patients. It's important for patients to understand that most disc disease improves on its own, and herniated discs often return to normal (see natural course of disc disease). With only a few exceptions, watchful waiting is appropriate to see if symptoms improve before imaging studies are performed, and surgery is considered.

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• TREATMENT | Spinal stenosis

• Overview
• The main treatments for spinal stenosis are conservative measures (e.g. physical therapy, injections, medications) and surgery
• In surgical treatment, the laminae of the vertebrae are often removed (laminectomy) to relieve pressure in the spinal canal (laminectomy illustration). Other decompressive procedures such as discectomy and foraminotomy can be performed. After decompression, a fusion is often performed to stabilize the vertebrae. Spinal fusion involves binding two vertebrae together with rods, screws, and a bone graft. The fused vertebrae are theoretically more stable and less likely to cause nerve impingement, particularly in patients with spondylolisthesis. (spinal fusion illustration)
• The first two studies detailed below compared surgery to conservative measures. The following three studies evaluated the risks and benefits of adding spinal fusion to decompressive surgery. The last study compared epidural injections to sham injections.

• STUDY
  Spinal Cord Burst Stimulation vs Placebo Stimulation for Chronic Radicular Pain, JAMA (2022) [PubMed abstract]
• Design: Randomized, placebo-controlled, crossover trial (N=50| length = 12 months) in patients with ≥ 6 months of radicular pain (average ≥ 5 on 10 point scale) after ≥ 1 decompressive or fusion procedure(s) for degenerative lumbar spine disease
• Treatment: All patients were implanted with a pulse generator connected to electrodes with leads that travel into the epidural space posterior to the spinal cord dorsal columns. Patients then received two 3-month periods of spinal cord burst stimulation and two 3-month periods of placebo stimulation in random order.
• Primary outcome: Change from baseline in the self-reported Oswestry Disability Index (ODI; range, 0 points [no disability] to 100 points [maximum disability]; the minimal clinically important difference was 10 points) score between periods with burst stimulation and placebo stimulation.
• Results:
• Mean baseline ODI score was 44.7
• Primary outcome (change in ODI): Stimulation periods -10.6, Placebo periods -9.3 (p=0.32)
• Findings: Among patients with chronic radicular pain after lumbar spine surgery, spinal cord burst stimulation, compared with placebo stimulation, after placement of a spinal cord stimulator resulted in no significant difference in the change from baseline in self-reported back pain–related disability.

• Summary
• Surgery vs conservative treatment - the SPORT trial had high crossover rates, making it difficult to draw any conclusions. In the smaller Spine study, crossover rates were low, and surgery was superior to conservative treatment for disability and pain outcomes. Overall, it is difficult to know the true effect of surgery when compared to conservative treatment since these trials lack blinding, and outcomes are subjective.
• Laminectomy/decompression +/- fusion - the small SLIP trial (N=66) found a small improvement with the addition of spinal fusion to decompressive surgery. The larger SSS Study and NORDSTEN-DS trial found no additional benefit with fusion. Overall, spinal fusion does not appear to enhance decompressive surgery, even in patients with significant spondylolisthesis.
• Epidural steroids - epidural steroid injections had no meaningful effect on spinal stenosis in the LESS trial. A significant effect from steroids was seen at 3 weeks, but this may have been due to systemic absorption of the steroids and unrelated to their placement around the spinal cord; the finding that cortisol levels were suppressed in patients receiving steroids supports this assumption. Given the cost and potential risk of such procedures (e.g. deadly meningitis outbreak of 2012), steroid epidural injections should not be recommended for most patients with spinal stenosis.
• Spinal cord stimulators - implantation of spinal cord stimulators has grown substantially in recent years, and pain management doctors often promote them in their marketing. The small study presented above (stimulator study) found that they did nothing for radicular pain after spinal decompression surgery.

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• TREATMENT | Vertebral compression fractures

• Overview
• Most vertebral compression fractures are treated conservatively with pain medications and short periods of bedrest. A small number of fractures may cause focal neurologic symptoms and spinal instability. These fractures may require surgery.
• A procedure called vertebroplasty is also used as a treatment. During vertebroplasty, an acrylic cement is injected through a needle into a compressed vertebra. Theoretically, the cement helps stabilize the vertebra and improves pain control. Vertebroplasty does not affect vertebral height or kyphosis risk.
• A variant of vertebroplasty called "balloon kyphoplasty" involves inflating a balloon in the vertebra before the cement is injected. The balloon inflation is supposed to help restore vertebral height.
• Vertebroplasty has become exceedingly popular in recent years. Early on, a number of unblinded studies comparing vertebroplasty to conservative treatment found it to be superior for pain relief. Vertebroplasty was then compared to a sham procedure in a handful of trials, and its effects were less convincing. Three of those trials are detailed below.

• Bracing
• Hard and soft bracing is sometimes used to treat compression fractures
• A small study involving 60 patients published in the The Journal of Bone and Joint Surgery (2014) found no benefit with either hard or soft bracing in patients with osteoporotic compression fractures. The study looked at disability, pain, and changes in anterior body compression ratios. [PMID 25471910]

• Summary
• The VAPOUR trial found a benefit with vertebroplasty, while the other two trials did not. One hypothesis for the conflicting results is that most subjects in the VAPOUR trial were treated within 3 weeks of fracture diagnosis, while the length between fracture and treatment was longer in the negative trials. The authors of the VERTOS trial also note that more than 80% of participants in the VERTOS sham group believed that they had received the intervention compared to 54% in the VAPOUR trial. These differences in the placebo effect may have contributed to the contradictory results.
• In conclusion, vertebroplasty may be of some benefit in patients with acute fractures (< 3 weeks), but its effects are not overwhelming

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• TREATMENT | TENS units

• Overview
• Transcutaneous electrical nerve stimulation (TENS) units are widely used to treat LBP
• TENS units deliver electrical stimulation to the nerves in the lower back via electrodes placed on the skin
• A study that compared TENS units to sham TENS units is detailed below

• Summary
• In the study above, TENS units had no effect of function and disability but they did improve some pain outcomes. Another study published in 1990 found no effect of TENS units on back pain. [PMID 2140432]
• TENS units do not improve function in patients with LBP, and their effect on pain is inconclusive.

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• Treatment | Radiofrequency denervation

• Overview
• It has been hypothesized that nonspecific back pain may originate from irritated nerves that surround the facet joints, sacroiliac joints, and intervertebral discs
• A procedure called radiofrequency denervation (RD) was developed to treat this type of pain. Potential candidates for RD are first screened with numbing injections around the target nerves. If the injections produce pain relief, then the patient may proceed to RD. During RD, a doctor places a cannula under fluoroscopy in the area of the target nerve. An electrical current is then applied that supposedly damages the pain-conducting fibers.
• RD is frequently advertised by pain clinics, and its popularity has grown substantially in recent years
• A study that compared RD to standard care is detailed below

• Summary
• The study above found no meaningful effect of RD on chronic LBP. The study was unblinded so RD was at an advantage given that the placebo effect from these types of procedures can be quite large. Despite this, it still had no meaningful effect.

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• MEDICATIONS FOR LBP

• Nonsteroidal anti-inflammatory drugs (NSAIDS)
• NSAIDs are widely prescribed to help alleviate LBP. In trials, they have generally been found to be effective. [51]

• Acetaminophen (Tylenol®)
• Acetaminophen is widely available and often used to treat LBP. A large trial published in 2014 found that it was no better than placebo in shortening recovery time. [PMID 25064594]

• Muscle relaxants
• Carisoprodol (Soma®)
• Carisoprodol has been shown in clinical trials to be superior to placebo for relief of low back pain
• Carisoprodol has abuse potential and should be used judiciously [54]
• Cyclobenzaprine (Flexeril®)
• A meta-analysis in the Archives of Internal Medicine looked at placebo-controlled trials involving cyclobenzaprine. The analysis found that patients given cyclobenzaprine were five times more likely to experience overall improvement of symptoms compared to patients given placebo (10 trials) [PMID 11434793]
• A randomized controlled trial of patients with nonspecific LBP (JAMA 2015) found no significant effect of cyclobenzaprine on functional outcomes when compared to placebo or oxycodone [PMID 26501533]
• Metaxalone (Skelaxin®)
• A study published in 2019 compared baclofen to metaxalone, tizanidine, and placebo in patients presenting to the ER with acute nonspecific low back pain. The study found no significant effect of any of the drugs when compared to placebo. See muscle relaxers for LBP for more.
• Methocarbamol (Robaxin®)
• A study published in the Ann Emerg Med (2018) compared the addition of methocarbamol, orphenadrine, or placebo to naprosyn in patients presenting to the ER with nonspecific LBP. The study found that neither methocarbamol or orphenadrine improved outcomes when compared to placebo. See orphenadrine vs methocarbamol for more.
• Tizanidine (Zanaflex®)
• A study published in 2019 compared baclofen to metaxalone, tizanidine, and placebo in patients presenting to the ER with acute nonspecific low back pain. The study found no significant effect of any of the drugs when compared to placebo. See muscle relaxers for LBP for more.

• Benzodiazepines
• Benzodiazepines (e.g. Valium, Xanax) are sometimes prescribed for low back pain
• A randomized controlled trial compared valium + naproxen to placebo + naproxen in patients presenting to the ER with nonradicular LBP for ≤ 2 weeks. The trial found that valium was no better than placebo in improving function at 1 week and 3 months of follow-up. [PMID 28187918]

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• MEDICATIONS | Gabapentin and pregabalin

• Overview
• Gabapentin and pregabalin are structurally related and share a similar mechanism of action. Both drugs are anticonvulsants, but they are primarily used to treat neuropathic pain.
• A study that compared gabapentin to epidural steroid injections in patients with sciatica is detailed below. Two pregabalin studies that looked at its effectiveness in sciatica and spinal stenosis are also reviewed.

• STUDY
  Pregabalin vs Placebo for Acute and Chronic Sciatica, NEJM (2017) [PubMed abstract]
  • Design: Randomized placebo-controlled trial (N=209 | length = 8 weeks) in patients with sciatica for at least 1 week and less than 1 year
  • Treatment: Pregabalin titrated to a maximum of 600 mg/day vs Placebo for 8 weeks
  • Primary outcome: Leg-pain intensity score on a 10-point scale (with 0 indicating no pain and 10 the worst possible pain) at 8 weeks
  • Results:
  • Primary outcome: Pregabalin - 3.7, Placebo - 3.1 (p=0.19)
  • Findings: Treatment with pregabalin did not significantly reduce the intensity of leg pain associated with sciatica and did not significantly improve other outcomes, as compared with placebo, over the course of 8 weeks. The incidence of adverse events was significantly higher in the pregabalin group than in the placebo group.

• STUDY
  Pregabalin vs Diphenhydramine for Neurogenic Claudication in Spinal Stenosis, Neurology (2015) [PubMed abstract]
  • Design: Randomized controlled crossover trial (N=29 | length = 33 days) in patients with spinal stenosis and neurogenic claudication
  • Treatment: Pregabalin 150 mg twice daily vs Diphenhydramine 12.5 mg twice daily. Patients received each treatment for 13 days before crossing over to the other treatment with a 7 day washout period in between.
  • Primary outcome: Time to first moderate pain symptom (Numeric Rating Scale (0 - 10) score ≥ 4) during a 15-minute treadmill test
  • Results:
  • Primary outcome: No significant difference was found between pregabalin and active placebo for the time to first moderate pain symptom (p=0.61)
  • Findings: Pregabalin was not more effective than active placebo in reducing painful symptoms or functional limitations in patients with neurogenic claudication associated with lumbar spinal stenosis

• Summary
• The gabapentin study found no difference between epidural steroid injections and gabapentin for radicular nerve pain. The one-month outcomes are valid, but the three-month outcomes cannot be considered valid because nonresponders were excluded from the study after one month. Another study that compared epidural injections to sham injections is detailed above (see epidural injection vs sham). It's unclear from this study what the true benefit of either intervention is since there was no placebo group.
• The pregabalin studies found that it offered no benefit in either sciatica or spinal stenosis

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• MEDICATIONS | Antidepressants

• Overview
• Antidepressants are sometimes used to treat nonspecific LBP
• Duloxetine (Cymbalta®) has been FDA-approved to treat chronic musculoskeletal pain including nonspecific LBP. Other antidepressants are not FDA-approved for this indication. One of the larger studies that evaluated duloxetine is detailed below.

• Summary
• In this industry-funded study, duloxetine had a very modest effect on nonspecific low back pain while causing significantly more side effects
• A Cochrane meta-analysis that included ten placebo-controlled trials found that antidepressants were no more effective than placebo for nonspecific LBP [PMID 18253994]

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• MEDICATIONS | Corticosteroids

• Overview
• Corticosteroids are frequently prescribed to treat LBP, particularly acute sciatica. They are typically given as oral tapers or intramuscular injections.
• The study below compared a prednisone taper to placebo in patients with acute sciatica

• Summary
• This study found that an oral steroid taper significantly improved function in patients with sciatica after 3 weeks. Steroids had no effect on pain.
• The effect size was modest (6% difference in the ODI scale when compared to placebo), and it occurred at the cost of more side effects (insomnia, nervousness, increased appetite)
• It's important to note that because of steroid side effects, 75% of the subjects in the treatment group correctly identified their randomization group. This unblinding likely biased the study towards the treatment group and probably accounted for some of the effect seen. In addition, NSAIDs, a common treatment for sciatica, were not allowed during the active treatment phase, so it's unclear how their use would have affected the results.
• In conclusion, the effects of an oral steroid taper on sciatica are minimal at best and probably not worth the associated side effects in most patients

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• MEDICATIONS | Glucosamine

• Overview
• Glucosamine is hypothesized to have cartilage-restoring effects and anti-inflammatory properties. Because of this, it is often used to treat osteoarthritis.
• The study detailed below compared glucosamine to placebo in patients with osteoarthritic changes of the lumbar spine

• Summary
• Glucosamine had no effect on LBP outcomes in patients with degenerative lumbar osteoarthritis. This is consistent with studies in knee osteoarthritis where glucosamine also has typically shown no effect (see glucosamine for knee OA)

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• SPONDYLOLYSIS AND SPONDYLOLISTHESIS

• Definitions
• Spondylolysis
• Each vertebrae has four joints - two joints with the vertebra above it, and two joints with the vertebra below it
• The bone that connects the upper and lower joint on each side is called the pars interarticularis
• In some people, this bone forms a stress fracture
• A stress fracture in the pars interarticularis is referred to as spondylolysis
• Spondylolysis is present in 3 - 7% of the population
• Spondylolysis typically has no symptoms
• Spondylolysis can lead to spondylolisthesis (see below)
• Spondylolysis - illustration of spondylolysis
• Spondylolisthesis
• Spondylolisthesis is a condition where one vertebral body is displaced forward in relation to the one below it
• Spondylolisthesis may occur secondary to spondylolysis. Spondylolisthesis that results from spondylolysis is sometimes referred to as "isthmic spondylolisthesis" or "spondylolytic spondylolisthesis."
• Spondylolisthesis may also result from degenerative changes in the pars interarticularis joints that lead to laxity in the joints. The laxity allows the vertebra to slip forward over the underlying vertebra. Spondylolisthesis can contribute to spinal stenosis.
• Spondylolisthesis - illustration of spondylolisthesis
• Degree of spondylolisthesis
• The degree of spondylolisthesis is typically expressed as a percentage using the Meyerding method. In this method, the anterior-posterior length of the overhanging part of the upper vertebra is divided by the anterior-posterior diameter of the top surface of the lower vertebra. The ratio is then multiplied by 100 and expressed as a percent. Depending on the percent, a grade is then assigned. [74]
• Grade I: ≤ 25%
• Grade II: 26 - 50%
• Grade III: 51 - 75%
• Grade IV: 76 - 100%
• Grade V: 100% (spondyloptosis)

• Prevalence
• Children and young adults
• In the general population, spondylolysis is found in 4 - 5% of children by the age of six years [70,71]
• In children with spondylolysis, some degree of spondylolisthesis is present in 50 - 74%. As patients age, the incidence of spondylolytic spondylolisthesis appears to increase with up to 81% of patients being affected in adulthood. [72]
• Older patients
• A population study published in Spine reviewed CT scans (N=188) from an unselected population of U.S. adults with an average age of 52 years
• The study found the following:
• Lumbar spondylolysis was present in 16.5% of males and 5% of females
• Spondylolisthesis was present in 20.7% of patients
• Isthmic (spondylolytic) spondylolisthesis was present in 8.2% of patients
• Degenerative spondylolisthesis was present in 7.7% of men and 21.3% of women
• Prevalence of degenerative spondylolisthesis by age was as follows:
• < 40 years: 0%
• 40 - 49 years: 2.1%
• 50 - 59 years: 10.8%
• 60 - 69 years: 41.7%
• ≥ 70 years: 16.7% [73]

• Causes
• Children and young adults
• In children and young adults, spondylolysis typically precedes spondylolisthesis
• The cause of spondylolysis in children and young adults is largely unknown. It is believed to be a stress fracture that results from overuse. Spondylolysis is seen more frequently in athletes who engage in sports that require frequent and extensive spine motion (e.g. gymnasts, figure skaters, dancers, divers).
• Spondylolysis and spondylolisthesis in children and young adults typically occurs at the L5 - S1 level. The degree of slippage is typically mild with about 79% being Grade I, 20% being Grade II, and 1% being Grade III. [72]
• Older patients
• In older patients (≥ 40 years), spondylolysis does not typically precede spondylolisthesis. Spondylolisthesis occurs from degenerative changes in the pars interarticularis joint that create laxity in the joint. The laxity allows the vertebra to slip forward over the underlying vertebra.
• Degenerative spondylolisthesis typically occurs at the L4 - L5 level. The average degree of slippage is 14%. [74]

• Symptoms
• Children and young adults
• In most patients, spondylolysis and spondylolisthesis have no symptoms
• One study followed 27 children with spondylolysis/spondylolisthesis into adulthood. Four patients developed low back pain over 25 years [75]
• In more severe cases, back pain and symptoms of disc disease may develop
• Older patients
• In older patients, spondylolisthesis often leads to spinal stenosis
• Symptoms of spinal stenosis include pain that radiates across the buttocks and into the thigh and lower legs
• The pain may be worsened by prolonged walking or standing and relieved when leaning over or sitting

• Natural course
• Children and young adults
• In children, spondylolytic spondylolisthesis rarely progresses with only 4 - 5% of patients experiencing worsening in longitudinal studies
• Progression after adolescence is rare [72]
• Older patients (> 40 years)
• In older patients, progression of spondylolisthesis is more common
• In a study that followed 145 patients with degenerative spondylolisthesis for 10 years, spondylolisthesis progressed in 34% of patients. Progression did not correlate with change in symptoms.
• Despite the greater risk of progression, prognosis in spondylolisthesis is favorable. Only about 15% of patients who seek treatment ever require surgery. [74]

• Treatment
• Children and young adults
• In general, there is a lack of consensus and evidence on the appropriate treatment of spondylolisthesis in children and young adults
• Since the majority of cases are mild and asymptomatic, most patients will require no treatment or conservative measures only
• When slippage becomes severe (defined as > 50%) and/or symptoms become persistent, then surgery involving some type of lumbar fusion is often performed
• There are no long-term, randomized controlled trials that have compared surgery to other measures in lumbar spondylolisthesis in children and young adults [71,72]
• Older patients (> 40 years)
• The majority of older patients with degenerative spondylolisthesis do well with conservative treatment
• Patients who present with significant and persistent pain from radiculopathy, progressive neurological deficits, and/or bowel and bladder symptoms, will typically not do well and require surgery [74]
• See spinal stenosis treatment for more

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