Linking To And Excerpting From StatPearls’ “Back Pain”

Today, I review, link to, and excerpt from StatPearls‘ Back Pain. Vincent E. Casiano; Gurpreet Sarwan; Alexander M. Dydyk; Matthew A. Varacallo. Last Update: December 11, 2023.

All that follows is from the above resource.

Introduction

Back pain is one of the most common reasons for primary- and emergency-care consultations. An estimated $200 billion is spent annually on managing back pain. Additionally, work hours, productivity, and workers’ compensation are greatly reduced due to this condition.[1]

Back pain arises from a broad range of causes in adults and children, though most are mechanical in nature or have a nonspecific origin. Mechanical back pain comprises 90% of cases, so health providers can easily miss rare causes while focusing on common etiologies.[2][3]

Identifying red flags and determining the appropriate treatment are the most important aspects of back pain management. Most cases can be managed conservatively. Association with nerve dysfunction and other alarming signs warrants a thorough investigation and a multidisciplinary approach.[4]

Pharmacological treatments include pain relievers targeting peripheral and central neurologic pathways and muscle relaxants.[5] Various forms of physical therapy are available for individuals who prefer nonpharmacological approaches or recovering from injuries.[6] Acupuncture is an alternative therapy shown to improve back pain moderately. Surgery is reserved when the symptom is accompanied by severe nerve dysfunction or is due to serious causes like malignancy.[7][8] Back pain that does not resolve 6 weeks after acute injury warrants imaging by radiography, computed tomography (CT), or magnetic resonance imaging (MRI).

A thorough evaluation helps determine the cause of back pain and develop a tailored therapeutic plan. Eliminating the cause of this symptom profoundly improves patients’ functional capacity and quality of life.

Etiology

Back pain arises from various conditions, which can be classified into the following:[9]

• Traumatic: Back pain commonly results from direct or indirect contact with an external force. Examples are whiplash injury, strain, and traumatic fractures.
• Degenerative: Musculoskeletal structures can weaken over time due to aging, overuse, or pre-existing pathology. Conditions like intervertebral disk herniation and degenerative disk disease fall into this class.
• Oncologic: Anatomic structures of the back can develop primary or secondary malignant lesions. Pathologic fractures of the axial skeleton can arise as a complication.
• Infectious: Infections of the musculoskeletal structures in this region can arise from direct inoculation or spread from another source.
• Inflammatory: This category includes inflammatory conditions not caused by infection or malignancy. Examples are ankylosing spondylitis and sacroiliitis. Chronic inflammation can give rise to spinal arthritis.
• Metabolic: Calcium and bone metabolism can cause the symptoms. Osteoporosis and osteosclerosis are examples.
• Referred pain: Visceral organ inflammation can cause referred back pain. Examples are biliary colic, lung disease, and aortic or vertebral artery pathology.
• Postural: Spending long hours in an upright position can cause back pain. Pregnancy and certain occupations can predispose people to postural back pain.
• Congenital: Inborn conditions of the axial skeleton can cause the symptoms. Examples are kyphoscoliosis and tethered spinal cord.
• Psychiatric: Back pain may also present in patients with chronic pain syndromes and other mental health conditions. Malingering individuals may also claim to have back pain.

The problem’s duration must also be considered, as acute back pain often has different sources from chronic back pain. Thorough clinical evaluation and appropriate diagnostic examination are usually enough to determine the exact cause of this symptom. Depending on the findings, referral to specialists such as orthopedic surgeons, neurologists, rheumatologists, or pain management specialists may be necessary for further evaluation and treatment planning.

Epidemiology

Back pain is widespread among adults. Studies show that up to 23% of adults worldwide suffer from chronic low back pain, with one-year recurrence rates reaching 24% to 80%.[10][11]. Lifetime back pain prevalence is as high as 84% in adults.[12]

Back pain is less prevalent among pediatric patients than in adults. One Scandinavian study revealed that the point prevalence of back pain was approximately 1% for 12-year-olds and 5% for 15-year-olds. By age 18 for girls and age 20 for boys, 50% would have already experienced at least one episode of back pain.[13] The lifetime prevalence of back pain in adolescents increases steadily with age until it approximates adult levels by 18 years.[14]

History and Physical

Determining the cause of back pain starts with a thorough history and physical examination. The onset of the pain must be established early. Acute back pain, which lasts less than 6 weeks, is usually precipitated by trauma or sudden changes in the course of a chronic illness like malignancy. Chronic cases, which last longer than 12 weeks, may be mechanically related or due to longstanding conditions.

Information about what provokes or alleviates the pain must be elicited. Besides providing additional clues to the diagnosis, knowing these factors guides the clinician in determining the appropriate pain control measures for the patient.

Red flags on history or physical exam warrant imaging and other diagnostic tests. Listed below are the signs to watch out for in each group:

In adults:[18][19]

• Malignancy:

  • History: History of metastatic cancer, unexplained weight loss
  • Physical exam: Focal tenderness to palpation in the setting of risk factors
• Infection:

  • History: Spinal procedure within the last 12 months, intravenous drug use, immunosuppression, prior lumbar spine surgery
  • Physical exam: Fever, wound in the spinal region, localized pain, tenderness
• Fracture:

  • History: Significant trauma (relative to age), prolonged corticosteroid use, osteoporosis, and age older than 70 years
  • Physical exam: Contusions, abrasions, tenderness to palpation over spinous processes
• Neurologic:

  • History: Progressive motor or sensory loss, new urinary retention or incontinence, new fecal incontinence
  • Physical exam: Saddle anesthesia, anal sphincter atony, significant motor deficits of multiple myotomes

In pediatric patients:[20][21]

• Malignancy:

  • History: Age younger than 4 years, nighttime pain
  • Physical exam: Focal tenderness to palpation in the setting of risk factors
• Infectious:

  • History: Age younger than 4 years, nighttime pain, history of tuberculosis exposure
  • Physical exam: Fever, wound in the spinal region, localized pain, and tenderness
• Inflammatory:

  • History: Age younger than 4 years, morning stiffness lasting longer than 30 minutes, improving with activity or hot showers
  • Physical exam: Limited range of motion, localized pain, and tenderness

Fracture:

• History: Activities with repetitive lumbar hyperextension (as in sports activities like cheerleading, gymnastics, wrestling, and football)
• Physical exam: Tenderness to palpation over spinous process, positive Stork test

Evaluation

History and physical examination are enough to determine the cause of back pain in most cases. Early imaging in the adult population correlates with worse outcomes, as it tends to result in more invasive treatments that provide little benefit to patients.[22][23] The same is true in the pediatric population. However, the presence of concerning signs warrants diagnostic testing. In adults, back pain persisting longer than 6 weeks despite appropriate conservative management is also an indication for imaging. In the pediatric population, the recommendation is to perform imaging tests for continuous pain lasting more than 4 weeks.[91]

Plain anteroposterior and lateral (APL) films of the axial skeleton can detect bone pathology (see Image. Multiple Myeloma Involving the Spine). Magnetic resonance imaging (MRI) is indicated for evaluating soft tissue lesions, such as the nerves, intervertebral disks, and tendons. Both imaging modalities can detect signs of malignancy and inflammation, but MRI is preferable when the soft tissues are involved.[24][25] Bone scans may show osteomyelitis, diskitis, and stress reactions but remain inferior to MRI in evaluating these conditions.[26]

Adolescents with MRI evidence of disk herniation need a computed tomogram (CT) to confirm or rule out apophyseal ring separation, which occurs in 5.7% of these patients.[27]

aboratory tests may be necessary in some cases of back pain. Rheumatologic assays such as HLA-B27, antinuclear antibody (ANA), rheumatoid factor (RF), and Lyme antibodies are typically not helpful, being nonspecific for back pain.[28][29] However, the inflammatory markers C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) can be useful.[30] A complete blood count (CBC) and blood cultures may aid in diagnosing inflammatory, infectious, or malignant etiologies. High lactate dehydrogenase (LDH) and uric acid levels are commonly found in conditions associated with rapid marrow turnover like leukemia.[31]

Differential Diagnosis of Back Pain in Adults

• Lumbosacral muscle strains and sprains: Usually from a traumatic incident or repetitive overuse; pain worsens with movement and gets better with rest; range of motion is restricted; muscles are tender to palpation
• Lumbar spondylosis: The patient is typically older than 40 years; hip pain may be present; pain occurs with lower limb extension or rotation; neurologic exam is usually normal
• Disk herniation: Usually involves the L4 to S1 segments; may have associated paresthesia, sensory change, loss of strength or reflexes, depending on the severity and nerve root involved
• Spondylolysis and spondylolisthesis: Caused by repetitive spinal stress; may present with back pain radiating to the gluteal area and posterior thighs; neurologic deficits follow the L5 distribution.[50]
• Vertebral compression fracture: Localized back pain worsening with flexion; point tenderness on palpation; may be acute or chronic; steroid use, vitamin D deficiency, and osteoporosis are risk factors
• Spinal stenosis: Accompanied by leg sensory and motor weakness relieved with rest (neurologic claudication); neurologic exam may be normal initially but progress with increasing stenosis
• Tumor: May be accompanied by unexplained weight loss, focal tenderness to palpation, or malignancy risk factors on history (97% of spinal tumors are metastatic).[51]
• Infection: The patient may have a history of spinal surgery in the last 12 months, intravenous drug use, or immunosuppression; accompanying symptoms include fever, wound in the spinal region, localized pain, and tenderness, most commonly from vertebral osteomyelitis, diskitis, septic sacroiliitis, epidural abscess, and paraspinal muscle abscess; consider tuberculosis if the patient comes from a developing country.[52]
• Fracture: May arise from trauma, prolonged corticosteroid use, and osteoporosis; common among patients older than 70 years; associated findings include contusions, abrasions, tenderness to palpation over spinous processes

Differential Diagnosis of Back Pain in Children and Adolescents

• Tumor: May present with fever, malaise, weight loss, nighttime pain, and recent onset scoliosis; osteoid osteoma is the most common tumor presenting with back pain easily relieved by NSAIDs.[53][54][55]
• Infection: Associated symptoms include fever, malaise, weight loss, nighttime pain, and recent-onset scoliosis; patients may refuse to walk; most common conditions are vertebral osteomyelitis, diskitis, septic sacroiliitis, epidural abscess, and paraspinal muscle abscess; consider epidural abscess if neurologic deficits and radicular pain also appear.[56][57]
• Disk herniation and slipped apophysis: May present with acute back pain, radicular pain, and recent-onset scoliosis; physical findings include positive SLR test and pain on spinal forward flexion.
• Spondylolysis, spondylolisthesis, and posterior arch lesion: Acute-onset back pain presents with radicular pain; hamstring tightness may be present; physical findings include positive SLR test and pain on spinal extension.
• Vertebral fracture: Trauma is the most common cause; acute back pain may be associated with other injuries; neurologic deficits may be present on physical examination; stress fractures may present insidiously and produce progressive postural changes.
• Muscle strain: Acute back pain is typically associated with muscle tenderness without radiation.Scheuermann’s kyphosis: Back pain is chronic and associated with rigid kyphosis.
• Inflammatory spondyloarthropathies: Pertinent findings on history include chronic pain, morning stiffness lasting greater than 30 minutes, and sacroiliac joint tenderness.
• Psychological disorder, eg, conversion and somatization disorder: Persistent subjective pain with normal physical findingsIdiopathic scoliosis: Most commonly asymptomatic, with a positive Adam test; back pain may be due to another cause.[58]

Pearls and Other Issues

The following are the practice pearls worth remembering in back pain management:

For Adults

• History and physical examination usually suffice for evaluating atraumatic, acute back pain without clinical red flags. Wait 6 weeks for symptom resolution before ordering imaging tests.[78][79]
• Patient education focusing on remaining active is the first-line treatment for nonspecific back pain. Studies show that pharmacologic and physical therapy do not consistently benefit patients with back pain. However, clinicians may consider NSAIDs, opioids, and SNRIs like duloxetine as second-line therapy for nonspecific chronic low-back pain. These medications are more effective than placebo for this condition.[80][81]
• Acetaminophen, antidepressants (except SNRIs), lidocaine patches, and TENS are not consistently more effective than placebo in treating chronic low-back pain.[82][83]
• Consider a physical therapy referral for the McKenzie technique to reduce recurrence risk.[84][85]

For Children

• Children with transient back pain and a history of minor injury but without significant physical findings can be treated conservatively without further evaluation.
• Abnormal physical findings, constant pain, nighttime pain, or radicular pain are indications for further evaluation.[86]
• Plain APL films are recommended as the first-line radiographic studies.
• Consider laboratory tests in the presence of clinical red flags. Thoracic malignancy and infection are more likely in children than adults, especially those younger than 4 years.[87]

Enhancing Healthcare Team Outcomes

If the primary care physician prescribes medications, the pharmacist can help educate patients about the prescribed drugs’ back pain-specific benefits and risks. Intake instructions and the potential risks of overdose must be emphasized. The pharmacist should not hesitate to contact the primary care provider to clarify a patient’s prescription.

Obesity in a patient with back pain is associated with adverse outcomes. Patients can work with nutritionists to make healthier dietary choices and maintain a healthy weight. If a patient is obese, an obesity medicine specialist can prescribe antiobesity medications as adjunct to lifestyle modifications to help them lose significant weight.

The physical therapist can prescribe the appropriate strength and endurance exercises for managing back pain and preventing recurrences. Physical therapy is effective in weaning patients with back pain from opioid use.[89] An occupational therapist can provide ergonomic guidance and recommend assistive devices to manage back pain in work and home settings.

The radiologist helps the primary care physician interpret imaging findings. These specialists can also make recommendations for additional imaging tests if necessary.

The primary care physician can make referrals to other specialists as needed. A pain specialist can help patients with chronic back pain by modifying their current pharmacologic treatment regimen or performing a pain-management procedure. A rheumatologist may be consulted for back pain associated with signs of chronic inflammatory disease. Severe radiculopathy or rapid neurological changes are indications for prompt neurosurgery referral. A mental health therapist can teach stress-coping techniques, administer cognitive behavioral therapy, and prescribe other treatments appropriate for back pain with a prominent psychological component.[90] Alternative medicine providers may also be instrumental in improving patient function.