Back pain in children and adolescents: Evaluation

INTRODUCTION — Although most children with back pain have benign muscle-related or nonspecific pain, some children have a serious underlying congenital or acquired cause (eg, tethered cord, osteomyelitis of the vertebral body, inflammatory arthritis, bone tumor, spinal cord tumor).

The evaluation of the child with back pain is reviewed here. Causes of back pain in children and adolescents are discussed separately. (See "Back pain in children and adolescents: Causes".)

EPIDEMIOLOGY — Transient back pain is relatively common in children, particularly after early adolescence [1-6]. Most children with back pain have mild, nondisabling symptoms and do not seek medical care. The prevalence and most common causes vary with the population and evaluation setting.

The incidence of back pain increases with linear growth and pubertal development [7]. In a large cross-sectional survey including more than 5000 children and young adults, 7 percent of 12-year-olds had had at least one episode of low-back pain [8]. The cumulative incidence increased to 50 percent by age 18 years in females and 20 years in males (figure 1).

The prevalence of back pain in adolescents appears to be increasing [9,10]. On any given day, the prevalence was approximately 1 percent in 12-year-olds, 5 percent in 15-year-olds, and 10 percent during the early 20s (figure 2).

Back pain is an uncommon complaint in the emergency department. In one study, back pain accounted for <0.4 percent of visits to the emergency department of an urban pediatric tertiary care center [11]. Almost 90 percent of the 225 children with back pain had symptoms for <4 weeks at the time of presentation.

Back pain in schoolchildren has been associated with female sex, increased time watching television, negative scores on affect scales, and a family history of back pain [12,13]. Vigorous physical activity has been associated with an increased risk of self-reported back pain, while moderate physical activity is protective [14,15].

Back pain resolves in most children. In a longitudinal cohort, only 7 percent of the 262 participants who responded at age 9, 13, and 15 years of age reported back pain at all three assessments [16]. In another longitudinal cohort, 25 percent of schoolchildren reported back pain at the initial assessment (age 11 to 14 years); 26 percent of these (approximately 7 percent of the entire cohort) reported persistent pain at reevaluation one and four years later [4].

CAUSES OF BACK PAIN IN CHILDREN — Most children with back pain have benign or nonspecific musculoskeletal pain or minor trauma (table 1A) [17,18]. Less common causes include infection, inflammatory conditions, and neoplasm (table 1B). (See "Back pain in children and adolescents: Causes".)

In most large published series, including those from referral centers, the majority of children with back pain receive no definitive diagnosis [11,19-23]. Nonspecific musculoskeletal pain accounts for at least 50 percent of cases [19-21,24].

The frequency of specific causes depends upon the population studied:

●In observational studies of children who present to orthopedic hospitals or clinics for evaluation of back pain, skeletal causes predominate (eg, spondylolysis with or without spondylolisthesis, Scheuermann kyphosis, scoliosis, osteoid osteoma), but serious infections and tumors also occur [19,21,25,26].

●In an observational study of 225 children who were evaluated in the emergency department, common causes of back pain included trauma (25 percent), muscle strain (24 percent), sickle cell crisis (13 percent), idiopathic pain (13 percent), urinary tract infection (5 percent), and viral illness (4 percent) [11].

●In the primary care setting, as well as in some specialty clinics, overloaded school backpacks are a potential cause of back pain in children, though prospective studies have not consistently confirmed a correlation [27-29].

INITIAL CLINICAL EVALUATION — History and physical examination often are sufficient to suggest causes that require specific treatment, or monitoring (table 1A-B), although additional evaluation is usually necessary to confirm the diagnosis, particularly for children with warning signs of serious underlying causes (table 2).

Warning signs — Warning signs of potentially serious causes of back pain include [20,30-32]:

●Abnormal neurologic findings (eg, asymmetric reflexes, weakness, extensor plantar response, low rectal tone [in children with indications for rectal examination], bowel or bladder dysfunction)

●History of acute or repetitive trauma (particularly lumbar hyperextension)

●Pain that radiates below the buttocks

●Pain that is severe (eg, interferes with activity), constant (eg, unrelated to activity), occurs at night, or is progressive

●Fever with or without other systemic findings (eg, weight loss)

●Morning stiffness

●History of malignancy

●History of exposure to tuberculosis

●Age <10 years

Back pain related to major trauma with concern for acute spinal fracture or spinal cord injury is discussed separately. (See "Thoracic trauma in children: Initial stabilization and evaluation" and "Approach to the initially stable child with blunt or penetrating injury" and "Acute traumatic spinal cord injury".)

Pain characterization — Pain is characterized in terms of quality, location and radiation, and exacerbating or relieving factors and activities.

Pain is characterized by asking the following questions [17,33-36]:

●What is the exact location of the pain? Does the pain radiate?

•Focal pain suggests localized infection, inflammatory arthritis, or malignancy. As an example, patients with spondylolysis may localize pain to the affected side rather than the midline and are able to indicate a discrete (fingertip) location of pain more frequently than patients with common musculoskeletal back pain [37].

•Nonspecific lower back pain that radiates from the back into one or both buttocks suggests a simple sprain or strain.

•Pain that radiates from the lower back to the legs in a dermatomal distribution (ie, radicular pain) is the major historical finding in patients with a herniated disc. The classic features are aching pain in the buttock and paresthesias radiating into the posterior thigh and calf or into the posterior lateral thigh and lateral shin. In painful mononeuropathies and radiculopathies, the area of pain and sensory abnormality may extend beyond the sensory distribution of a peripheral nerve or beyond the dermatome of a root or dorsal root ganglion.

Pain that radiates from the back to below the knee is more likely to indicate a true radiculopathy; a history of persistent leg numbness or weakness further increases the likelihood of neurologic involvement [38,39].

Pain that radiates from the upper abdomen to the back or right shoulder may indicate referred pain (eg, cholecystitis, pancreatitis).

•Widespread pain (ie, not limited to the back) may suggest a pain amplification disorder (eg, fibromyalgia) [4,35]. (See "Fibromyalgia in children and adolescents: Clinical manifestations and diagnosis".)

●When and how did the symptoms begin?

•Pain with acute onset suggests trauma (eg, muscle strain, herniated vertebral disc) [36,40].

•Pain with gradual onset may be caused by discitis, muscular strain, hyperlordotic back pain, transitional vertebrae, or inflammatory arthritis [17,41].

•Chronic pain suggests an ongoing process (eg, inflammatory, musculoskeletal [eg, Scheuermann kyphosis]) or pain amplification/chronic pain syndrome (eg, fibromyalgia) [40].

●When does it the pain occur?

•Constant back pain (unchanged with activity) and nocturnal pain suggest neoplasm, infection, inflammatory arthritis, or nerve root compression.

•Pain during activities that require extension of the lumbar spine may indicate spondylolysis or spondylolisthesis.

•Pain during activities that require flexion of the spine may indicate a herniated disc or apophyseal ring fracture.

●What makes the pain better or worse?

•Pain that is relieved by nonsteroidal anti-inflammatory drugs (NSAIDs) can indicate osteoid osteoma or inflammatory arthritis [35], although NSAIDs may also relieve back pain from other causes. (See "Nonmalignant bone lesions in children and adolescents", section on 'Osteoid osteoma'.)

•Pain that is increased by coughing, straining (ie, Valsalva maneuver), standing, or sitting and is relieved by lying down suggests nerve root pain.

•Pain that is worse when the patient is lying in bed suggests pain originating in the peripheral nerves or lumbosacral plexus.

•Back pain and stiffness that is worse in the morning and improves with exercise suggests inflammatory arthritis, such as ankylosing spondylitis or another spondyloarthropathy. (See "Spondyloarthritis in children".)

•Pain resulting from an anatomic derangement (eg, kyphosis, spondylolysis) tends to feel best in the morning and worsen during or after activity.

●How does the patient describe the pain?

•Nerve root pain usually is brief, sharp, and shooting.

•Pain originating in the peripheral nerves or lumbosacral plexus tends to be described as burning, like pins and needles, and "asleep" or numb in quality.

•Pain intensity that is out of proportion to clinical and imaging findings may indicate a pain amplification disorder (eg, fibromyalgia).

●Does the pain interfere with activity? (eg, Does the child participate in physical education classes? Has the child missed school because of back pain?)

•Interference with activity is a sign of severe pain, which is associated with a serious underlying cause (table 2).

•Pain that is associated with loss of social and school function out of proportion to objective findings suggests a pain amplification disorder (eg, fibromyalgia).

Other aspects of the history — Other aspects of the history that may suggest an underlying cause include:

●Past medical history

•Sickle cell disease – Patients with sickle cell disease may have back pain associated with acute vaso-occlusive episode, osteonecrosis, or infection. (See "Acute and chronic bone complications of sickle cell disease", section on 'Causes of bone or joint pain'.)

•Immune compromise – Immune compromise is a risk factor for osteomyelitis and pyomyositis.

•Malignancy – History of malignancy increases suspicion for spinal metastases.

•Glucocorticoid use – Glucocorticoid use may be associated with vertebral insufficiency fracture [35,36].

●Family history of inflammatory spondylitis increases suspicion for inflammatory arthritis [17].

●Psychosocial history

•Sexual activity in female adolescents may be associated with pelvic inflammatory disease or pregnancy.

•Sports participation and training – Sports associated with repetitive trauma, particularly lumbar hyperextension, increase the risk of spondylolysis and spondylolisthesis (table 3).

•Problems with peer relationships may be associated with persistent pain [4]. Sleep disturbance and psychosocial stress appear to explain some of the rise in prevalence of back pain among adolescents [10].

●Travel history – Travel to an area with endemic tuberculosis raises suspicion for tuberculosis spondylitis. (See "Epidemiology of tuberculosis", section on 'Global burden' and "Bone and joint tuberculosis", section on 'Spondylitis (Pott disease)'.)

Examination of the spine

●Inspection – The way the child moves, sits, and stands may help to identify an underlying cause [33,34].

•The child's posture may suggest a diagnosis (eg, kyphosis, scoliosis).

•Loss of lumbar lordosis may indicate discitis or spondylolisthesis [42].

•Hyperlordosis may indicate muscular low back pain [17].

•Differences in shoulder height, scapular prominence, flank crease, and pelvic symmetry can indicate scoliosis or discrepancy in leg lengths.

•Midline skin lesions (eg, dimples, hemangioma, hair patches), cavus feet, or calf atrophy may indicate underlying spinal cord lesions.

•Café-au-lait macules, if present, may indicate neurofibromatosis. (See "Neurofibromatosis type 1 (NF1): Pathogenesis, clinical features, and diagnosis".)

●Palpation – Palpation of the lower spine and paraspinal muscles may reveal tenderness, muscle spasms, and radiating pain.

•Thoracic tenderness is often present in Scheuermann kyphosis.

•Lumbosacral tenderness may be present in spondylolisthesis, intervertebral disc herniations, and lordotic low-back pain.

•A prominent spinous process may be palpable in children with spondylolisthesis.

•Tenderness over the sacroiliac joints may be seen in sacroiliitis.

●Range of motion – The range of motion of the spine, sacroiliac joints, and other joints should be assessed.

•The range of motion of the spine is assessed by asking the patient to touch their toes, extend the spine, and bend to the right and left.

-Limitations or asymmetry on forward bending may indicate spinal cord tumors, spondylolisthesis, disc herniations, discitis, or apophyseal ring fracture [40,43]. However, many normal children are unable to reach their toes when they bend forward from the waist with knees extended. Lumbar lordosis should reverse with forward bending.

-Pain elicited during the ipsilateral one-legged hyperextension test, in which the patient stands on one leg and leans backward (picture 1), was thought to suggest a stress reaction to the pars interarticularis (spondylolysis) [44]. However, the sensitivity and specificity of this test are poor. A negative test does not exclude spondylolysis, while a positive test is common with back pain from other causes [45-47].

Patients with spondylolysis are more likely to report pain with lateral bend, but this finding is common with other causes of back pain as well [37].

•Pain arising from the sacroiliac joints may be elicited by the "figure of four" (FABERE) maneuver (figure 3).

•An inflammatory cause such as ankylosing spondylitis or psoriatic arthritis is suggested by inflammation affecting other joints. Range of motion of the hip is particularly important and is best assessed with the patient in prone position, enabling simultaneous evaluation of internal rotation at both hips (figure 4).

Neurologic evaluation

●Observation for signs of radiculopathy or muscle weakness

•Involuntary knee flexion may indicate radiculopathy (flexion guards against root traction).

•Signs of muscle weakness include:

-Pelvic tilt (sagging of one buttock, suggests weakness of the gluteus maximus [S1] on the side that sags)

-Fasciculations

-Atrophy, indicated by asymmetry of calf and thigh circumference measurements, is rare

Severe atrophy raises suspicion for an extradural tumor (eg, neuroblastoma).

●Evaluation of deep tendon reflexes

•Abnormal knee reflexes may indicate nerve root impingement at L3-L4 [48].

•Abnormal ankle reflexes may indicate nerve root impingement at S1.

●Strength/nerve root involvement testing

•Ask the patient to [48]:

-Rise from a squatting position (evaluates strength of the proximal lower extremity muscles)

-Repeatedly rise up on the toes (evaluates gastrocnemius strength)

-Dorsiflex the ankles (evaluates L4 or L5); dorsiflexion of the ankles with the knee extended may increase sciatic pain by stretching the S1-L5 root

-Extend the great toe (evaluates L5)

•Total paralysis implies a lesion of multiple roots or peripheral nerves because muscles are innervated by more than one nerve root.

●Sensory testing – Although sensory deficits may be difficult to detect, a dermatomal distribution of loss of pinprick and touch sensation indicates and localizes root involvement (figure 5). A single root lesion usually causes only mild hypalgesia because root distributions overlap widely.

•L5 sensation can be tested in the web space of the great toe.

•S1 sensation can be tested at the lateral malleolus and posterolateral foot.

●Gait testing – Gait testing includes walking on heels and on toes (if developmentally appropriate).

•Spasticity, ataxia, and instability suggests a neurologic problem.

•A lurching or waddling (Trendelenburg) gait suggest gluteus medius weakness (L5).

•Refusal to walk may indicate discitis.

●Straight leg raising – The straight leg raising (SLR) test stretches nerves and can detect impingement of the spinal roots by herniated discs, spondylolisthesis, or other lesions.

The SLR test is performed with the patient lying flat on their back with the uninvolved foot resting on the table and the knee bent at 45 degrees. The involved leg is raised straight up, while the ankle is kept at 90 degrees of flexion and the knee is fully extended. This test also may be performed with the patient seated; the seated position reduces strain on the hamstrings, which may give a false positive test when performed in the supine position.

A positive SLR test elicits pain radiating down the leg or into the buttock. This pain must be distinguished from discomfort related to stretching of the hamstring. The pain usually is worsened by dorsiflexion at the ankle or pressure in the popliteal fossa, which stretches the tibial nerve.

Although the sensitivity and specificity of the SLR test for herniated discs in children have not been determined, it is helpful in assessing nerve root compression. In adults, the SLR test has a sensitivity of approximately 80 percent and a specificity of approximately 40 percent for disc herniation (ie, relatively few false negative results and many false positive results) [49]. Adult patients with a negative SLR test are unlikely to have a herniated disc; those with a positive SLR test may have a condition other than a herniated disc. Specificity increases if elevation of the contralateral leg also elicits symptoms down the involved side (the crossed SLR test).

General examination — Aspects of the general physical examination of the child or adolescent with back pain that may help in establishing a diagnosis include [35]:

●Vital signs – Fever or tachycardia may indicate systemic illness.

●Lymph nodes – Lymphadenopathy may indicate infection, malignancy, or inflammatory arthritis (eg, systemic juvenile idiopathic arthritis [JIA]).

●Chest – Tachypnea, crackles, or findings suggestive of consolidation (eg, decreased breath sounds) may indicate pneumonia.

●Abdomen – Abdominal mass, hepatomegaly, or splenomegaly may indicate malignancy, although malignancy is not excluded by their absence.

●Skin and nails

•Skin lesions (picture 2) and/or nail pitting (picture 3) may suggest psoriatic JIA.

•Café-au-lait macules may indicate neurofibromatosis. (See "Neurofibromatosis type 1 (NF1): Pathogenesis, clinical features, and diagnosis".)

●Musculoskeletal system

•Swelling, tenderness, and/or reduced range of motion in peripheral joints suggests spondyloarthritis, most characteristically affecting knees and ankles. Hip arthritis is suggested by loss of internal rotation in prone position. (See "Spondyloarthritis in children", section on 'Articular manifestations'.)

•Tenderness and/or swelling of the Achilles tendon insertion at the calcaneus can reflect enthesitis, another hallmark of spondyloarthritis. (See "Spondyloarthritis in children", section on 'Physical examination'.)

•Children with psoriatic JIA may have dactylitis (ie, sausage-like swelling of one or more toes and fingers (picture 4)). (See "Psoriatic juvenile idiopathic arthritis: Pathogenesis, clinical manifestations, and diagnosis", section on 'Dactylitis'.)

ADJUNCTIVE EVALUATION FOR CHILDREN WITH WARNING SIGNS

Diagnoses suggested by warning signs — The possible serious underlying causes of back pain in children vary with the warning sign (table 2). Some of the underlying conditions are discussed in multiple sections because they have more than one warning sign and the warning signs do not always occur simultaneously.

Children with warning signs of potentially serious causes of back pain require laboratory and/or imaging evaluation. The evaluation varies with the diagnostic concerns. (See 'Targeted laboratory evaluation' below and 'Imaging modalities' below.)

Neurologic abnormalities — Diagnostic possibilities in children of any age who have back pain and neurologic abnormalities (eg, asymmetric reflexes, weakness, extensor plantar response, low rectal tone, bowel or bladder dysfunction) include:

●Spinal epidural abscess (see "Spinal epidural abscess")

●Spinal cord tumor (see "Spinal cord tumors")

●Transverse myelitis (see "Transverse myelitis: Etiology, clinical features, and diagnosis")

●Nerve root compression

These conditions generally are evaluated with immediate imaging, usually with magnetic resonance imaging (MRI). [21,50]. (See 'Imaging modalities' below.)

Acute or repetitive trauma or pain that radiates below the buttocks — Diagnostic possibilities in children of any age who have back pain and acute or repetitive trauma (particularly lumbar hyperextension) or pain that radiates below the buttocks include:

●Spondylolysis or spondylolisthesis, which are associated with increased pain with spinal extension (see "Spondylolysis and spondylolisthesis in child and adolescent athletes: Clinical presentation, imaging, and diagnosis")

●Intervertebral disc herniation or apophyseal ring fracture, which are associated with increased pain with spinal flexion

These causes are evaluated by imaging, initially with radiographs, followed by MRI [21,50]. (See 'Imaging modalities' below.)

Nocturnal, constant, or severe pain — Diagnostic possibilities in children of any age with pain that occurs at night, is constant (ie, unrelated to activity), or is severe (ie, interferes with activity) are listed below. Additional evaluation with laboratory studies and/or imaging is necessary to establish the diagnosis. The imaging strategy and laboratory evaluation vary with the suspected condition [21,50]. (See 'Imaging modalities' below and 'Targeted laboratory evaluation' below.)

●Inflammatory arthritis – Morning stiffness is the hallmark of inflammatory arthritis. Pain is typically described as improving ≥30 minutes after activity and a warm shower, although some patients worsen again in the evening. Awakening with back discomfort and stiffness at night is common, presumably reflecting the effect of inactivity. Children with inflammatory sacroiliac arthritis may have pain with the "figure of four" (FABERE) maneuver (figure 3). The pain of inflammatory arthritis may improve with nonsteroidal anti-inflammatory drugs (NSAIDs). (See "Spondyloarthritis in children".)

●Osteoid osteoma – The pain of osteoid osteoma typically is relieved by NSAIDs. (See "Nonmalignant bone lesions in children and adolescents", section on 'Osteoid osteoma'.)

●Tethered cord or syringomyelia may be suggested by severe pain in a child with idiopathic scoliosis [51]. (See "Adolescent idiopathic scoliosis: Clinical features, evaluation, and diagnosis", section on 'History'.)

●Discitis. (See "Back pain in children and adolescents: Causes", section on 'Discitis'.)

●Vertebral osteomyelitis, including tuberculous osteomyelitis. (See "Hematogenous osteomyelitis in children: Clinical features and complications", section on 'Vertebral bodies and intervertebral discs' and "Hematogenous osteomyelitis in children: Evaluation and diagnosis" and "Bone and joint tuberculosis", section on 'Spondylitis (Pott disease)'.)

●Chronic nonbacterial osteomyelitis (CNO)/chronic recurrent multifocal osteomyelitis (CRMO) involving the vertebrae or pelvis. (See "Chronic nonbacterial osteomyelitis (CNO)/chronic recurrent multifocal osteomyelitis (CRMO)", section on 'Clinical manifestations'.)

●Sacroiliac joint infection – Children with sacroiliac joint infection may have pain with the "figure of four" (FABERE) maneuver (figure 3).

●Malignant tumor of the spine or spinal metastases (particularly in a child with a history of malignancy). (See "Overview of common presenting signs and symptoms of childhood cancer", section on 'Bone and joint pain'.)

●Tumor of the spinal cord. (See "Spinal cord tumors".)

●Nephrolithiasis. (See "Kidney stones in children: Clinical features and diagnosis".)

●Vaso-occlusive pain in a child with sickle cell disease. (See "Evaluation of acute pain in sickle cell disease".)

Fever — Fever with or without systemic findings may indicate spinal or paraspinal infection (eg, osteomyelitis, sacroiliac joint infection, epidural abscess, tuberculosis). (See "Back pain in children and adolescents: Causes".)

The combination of fever and weight loss may be associated with malignant tumors (eg, leukemia, lymphoma, Ewing sarcoma) or inflammatory bowel disease-associated arthritis. (See "Overview of common presenting signs and symptoms of childhood cancer", section on 'Bone and joint pain' and "Clinical manifestations and complications of inflammatory bowel disease in children and adolescents", section on 'Joints'.)

Diagnostic possibilities in children of any age who have back pain and fever with or without systemic findings are listed below. Additional evaluation with laboratory studies and/or imaging are necessary to establish the diagnosis. The imaging strategy and laboratory evaluation vary with the suspected condition [21,50]. (See 'Imaging modalities' below and 'Targeted laboratory evaluation' below.)

●Sacroiliac joint infection (may have pain with the "figure of four" (FABERE) maneuver (figure 3)). (See "Bacterial arthritis: Clinical features and diagnosis in infants and children", section on 'Older children and adolescents'.)

●Epidural abscess. (See "Spinal epidural abscess".)

●Malignant tumor (eg, leukemia, lymphoma, Ewing sarcoma). (See "Overview of common presenting signs and symptoms of childhood cancer", section on 'Bone and joint pain'.)

●Pyomyositis. (See "Primary pyomyositis", section on 'Clinical manifestations'.)

●Vertebral osteomyelitis, including tuberculous osteomyelitis. (See "Hematogenous osteomyelitis in children: Clinical features and complications", section on 'Vertebral bodies and intervertebral discs' and "Bone and joint tuberculosis", section on 'Spondylitis (Pott disease)'.)

●Extraspinal infection (eg, pyelonephritis, pneumonia, severe pelvic inflammatory disease, viral myalgia).

●Pancreatitis.

●Cholecystitis.

Other warning signs

●Morning stiffness – Morning stiffness in children of any age is the hallmark of inflammatory arthritis.

●History of malignancy – History of malignancy in children of any age may indicate spinal metastases.

●History of exposure to tuberculosis – The possibility of tuberculous spondylitis (Pott disease) must be considered in children of any age with a history of exposure to tuberculosis.

●Age <10 years – Benign causes of musculoskeletal back pain are very uncommon in young children. This increases concern for spinal infection (eg, discitis, osteomyelitis) and malignancy (eg, leukemia, Langerhans cell histiocytosis).

For children whose only warning sign is age <10 years, we obtain laboratory studies for suspected infection and malignancy as described below. We also obtain imaging with radiographs, usually followed by MRI. (See 'Targeted laboratory evaluation' below and 'Imaging modalities' below.)

Targeted laboratory evaluation — The laboratory evaluation for children with warning signs depends upon the suspected underlying condition (table 1B).

Suspected infection — For children with suspected spinal, paraspinal, or extraspinal infection (eg, fever, nocturnal pain), we usually obtain:

●Complete blood count (CBC) with differential, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP)

Although an abnormal CBC and/or elevated ESR or CRP may support a diagnosis of infection, the findings are nonspecific. Normal CBC, ESR, and CRP do not exclude infection.

●Blood culture

●Additional studies – Additional laboratory studies may be warranted depending upon the suspected site of infection.

•Additional cultures (eg, urine, bone)

•Urinalysis (eg, for suspected urinary tract infection, pelvic inflammatory disease) (see 'Suspected extraspinal pain' below)

Imaging for children with suspected infection is discussed below. (See 'Imaging modalities' below.)

Suspected malignancy — For children with suspected malignancy (eg, systemic findings, nocturnal pain, pain unrelated to activity), we usually obtain CBC with differential, ESR, and CRP. We also obtain lactate dehydrogenase and uric acid to evaluate accelerated hematopoietic turnover in leukemia and lymphoma.

Although an abnormal CBC and/or elevated ESR or CRP may support a diagnosis of malignancy, the findings are nonspecific. Normal CBC, ESR, and CRP do not exclude malignancy.

Suspected inflammatory arthritis — For children with suspected inflammatory arthritis (eg, morning stiffness, sacroiliac pain), we usually obtain CBC with differential, ESR, and CRP, although normal findings do not exclude the diagnosis.

We do not usually test for HLA-B27 antigen in children with back pain in whom underlying inflammatory arthritis (eg, ankylosing spondylitis, reactive arthritis, spondylitis related to psoriasis or inflammatory bowel disease) is being considered. It is rarely helpful in clinical practice. Most positive HLA-B27 tests in children with back pain are false positive results because HLA-B27 is relatively common (7 to 10 percent in the White population and exceeding 25 percent in some Scandinavian and Native American groups including Alaska Natives), but inflammatory spondylitis is rare [52-54]. False negative HLA-B27 results also occur in patients with inflammatory spondylitis.

Similarly, other common rheumatologic assays, such as rheumatoid factor, antinuclear antibody, and Lyme serology, are not usually indicated in the evaluation of children with back pain [55].

Suspected extraspinal pain — Urinalysis and other tests (eg, serum amylase, aminotransferases, and bilirubin) may be helpful in evaluating causes of back pain that are not related to the spine, including:

●Pyelonephritis (pyuria, bacteriuria)

●Pelvic inflammatory disease (pyuria)

●Appendicitis (pyuria)

●Nephrolithiasis (hematuria)

●Vaso-occlusive pain in children with sickle cell disease (hematuria, bilirubinuria, decreased specific gravity)

●Pancreatitis (elevated serum amylase)

●Cholecystitis (may be associated with mild elevations in serum aminotransferases, amylase, and bilirubin)

●Pregnancy

ADJUNCTIVE EVALUATION FOR CHILDREN WITHOUT WARNING SIGNS

Specific cause suspected — Among children and adolescents with back pain of <4 weeks' duration and no warning signs, findings from the history or physical examination may suggest a specific cause (table 1A).

If a specific cause is suspected, additional evaluation should proceed as indicated for the specific cause. Examples include:

●Scheuermann kyphosis (see "Back pain in children and adolescents: Causes", section on 'Scheuermann (juvenile) kyphosis')

●Scoliosis without activity-limiting pain in an adolescent (see "Adolescent idiopathic scoliosis: Clinical features, evaluation, and diagnosis")

No specific cause suspected — Well-appearing children with back pain of <4 weeks' duration who are without warning signs of potentially serious causes of back pain (table 2) and have a clear precipitating factor (eg, increase in physical activity) generally do not require laboratory tests or imaging. They usually have muscle-related, hyperlordotic (also called mechanical) low back pain or nonspecific musculoskeletal pain.

These children can receive a therapeutic trial of conservative measures, including [17,35]:

●Ibuprofen or acetaminophen for pain control

●Avoidance of pain triggers (eg, exercises associated with back pain)

●Physiotherapy to strengthen the lower back and improve posture

For children with hyperlordotic back pain, physiotherapy may also include abdominal strengthening, hamstring and thoracolumbar stretches, and antilordotic exercise [56].

Children with no specific cause of back pain identified should be reevaluated after four weeks. If their pain persists, it is reasonable to obtain a radiograph of the involved area. (See 'Imaging modalities' below.)

Causes of back pain in children without warning signs that may not be detected with history or examination and may not improve with conservative measures include:

●Intervertebral disc calcification

●Syringomyelia

●Transitional vertebra

IMAGING MODALITIES — Imaging of children and adolescents with back pain is directed by the clinical findings (table 1A-B). Consultation with the radiologist before advanced imaging techniques is helpful in minimizing exposure to radiation [35].

Imaging for children and adolescents with major trauma and concern for spinal fracture or spinal cord injury is discussed separately. (See "Thoracic trauma in children: Initial stabilization and evaluation" and "Approach to the initially stable child with blunt or penetrating injury" and "Acute traumatic spinal cord injury".)

●Radiographs – Initial imaging with anteroposterior and lateral radiographs of the area of interest usually is indicated for children with back pain and one or more of the following pathologic findings [50]:

•Constant pain

•Nocturnal pain

•Abnormal neurologic examination

•Radicular pain

•Pain for >4 weeks

Oblique views add little to the diagnostic yield [57,58]. For patients in whom inflammatory arthritis is suspected, MRI of the sacroiliac joints is a superior diagnostic modality and eliminates the need for plain radiographs. Plain radiographs of the sacroiliac joints (and attendant gonadal radiation) to evaluate possible sacroiliitis should be avoided because disease chronicity is usually too short to result in clear changes [59].

Radiographs may identify [17,23,60]:

•Scoliosis (image 1)

•Scheuermann kyphosis (image 2A-B)

•Spondylolysis and spondylolisthesis (image 3)

•Primary bone tumors

•Apophyseal ring fractures

•Disc space narrowing (suggestive of discitis)

•Vertebral collapse, which may occur in sickle cell disease (image 4) or chronic nonbacterial osteomyelitis (CNO)/chronic recurrent multifocal osteomyelitis (CRMO)

Follow-up imaging with advanced imaging modalities may be warranted for some of these conditions.

Normal radiographs do not exclude pathology in children with warning signs [17,50]. Follow-up imaging with MRI or other advanced imaging technique is usually warranted [50].

●MRI – MRI imaging is optimal for evaluation of the paraspinal and intraspinal soft tissues [50]. It may be warranted for children with specific diagnostic concerns, including:

•Abnormal neurologic examination (MRI of the entire spine without intravenous [IV] contrast)

If compression by tumor is a clinical concern, the administration of intravenous dexamethasone may be warranted while awaiting MRI. (See "Clinical features and diagnosis of neoplastic epidural spinal cord compression" and "Treatment and prognosis of neoplastic epidural spinal cord compression".)

•Suspected infection (eg, osteomyelitis, epidural or paraspinal infection), inflammatory arthritis, or malignancy of the spine (MRI with and without IV contrast)

•Suspected CNO/CRMO (see "Chronic nonbacterial osteomyelitis (CNO)/chronic recurrent multifocal osteomyelitis (CRMO)", section on 'Imaging')

•Nonbony spinal tumors (eg, neurofibroma)

•Spinal cord abnormalities (eg, inflammation [transverse myelitis], tumors [eg, lipoma], tethering, syrinx)

•Spondylolysis

•Herniated disc

•Inflammatory arthritis (imaging of sacroiliac joints)

●Bone scan – The utility of bone scan in children with back pain and warning signs (table 2) is limited because it does not detect soft tissue tumors or infections unless they impinge on bone [20].

Bone scan with single-photon emission computed tomography (SPECT) may be an alternative to MRI for identifying or characterizing spondylolysis [50]. (See "Spondylolysis and spondylolisthesis in child and adolescent athletes: Clinical presentation, imaging, and diagnosis", section on 'Diagnostic imaging'.)

Bone scan also may be helpful if multiple infectious, inflammatory, or neoplastic bony lesions are suspected [50]. Although bone scan may detect osteomyelitis or discitis, MRI is preferred because it has greater sensitivity and specificity and does not expose the child to ionizing radiation [50,61]. (See "Hematogenous osteomyelitis in children: Evaluation and diagnosis", section on 'Advanced imaging' and "Back pain in children and adolescents: Causes", section on 'Discitis'.)

●Computed tomography – CT provides excellent detail of the bones and may be useful in the evaluation of back pain that originated in the bones, including suspected [50]:

•Spondylolysis

•Primary bone tumors (eg, osteoid osteoma, osteoblastoma, aneurysmal bone cyst)

•Apophyseal ring fractures

Although CT is inferior to MRI for the evaluation of the paraspinal and intraspinal soft tissues, CT with contrast is an alternative for the evaluation of infection or abscess if MRI cannot be performed [50].

INDICATIONS FOR REFERRAL — Referral to a specialist for additional evaluation and management generally is warranted for children with specific diagnostic concerns, including:

●Spinal epidural abscess (neurosurgeon, orthopedic surgeon, neurologist, specialist in infectious diseases)

●Inflammatory arthritis (rheumatologist)

●Vertebral infection or collapse (orthopedic surgeon, specialist in infectious diseases)

●Scoliosis, spondylolysis, spondylolisthesis, disc herniation, benign bone tumor (orthopedic surgeon)

●Malignant bone tumor, spinal cord tumor, or other malignancy (oncologist, orthopedic surgeon, neurologist)

●Neurofibromatosis (geneticist, neurologist)

●Transverse myelitis (neurologist)

●Osteoporosis (endocrinologist)

These conditions are discussed separately. (See "Back pain in children and adolescents: Causes".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Spondylolysis and spondylolisthesis".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or email these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient education" and the keyword[s] of interest.)

●Beyond the Basics topic (see "Patient education: Back pain in children and adolescents (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Transient back pain is relatively common in children, particularly after early adolescence. Most children with back pain have benign or nonspecific musculoskeletal pain or minor trauma (table 1A). Less common causes include infection, inflammatory conditions, and neoplasm (table 1B). (See 'Epidemiology' above and 'Causes of back pain in children' above.)

●History and physical examination often are sufficient to suggest causes that require specific treatment or monitoring (table 1A-B), although additional evaluation is usually necessary to confirm the diagnosis, particularly for children with warning signs of serious underlying causes (table 2). (See 'Initial clinical evaluation' above.)

●The possible serious underlying causes of back pain in children vary with the warning sign (table 1B). Children with warning signs of potentially serious causes of back pain require laboratory and/or imaging evaluation. The evaluation varies with the diagnostic concerns. (See 'Adjunctive evaluation for children with warning signs' above.)

●Among children and adolescents with back pain of <4 weeks duration and no warning signs, findings from the history or physical examination may suggest a specific cause (table 1A). (See 'Adjunctive evaluation for children without warning signs' above and 'Specific cause suspected' above.)

●Well-appearing children with back pain of <4 weeks' duration who are without warning signs of potentially serious causes of back pain (table 2) and have a clear precipitating factor (eg, change in physical activity) generally do not require laboratory tests or imaging. They usually have muscle-related, hyperlordotic (also called mechanical) low back pain, or nonspecific musculoskeletal pain. They can receive a therapeutic trial of conservative therapy for four weeks. Imaging may be warranted if they do not respond to conservative measures. (See 'No specific cause suspected' above.)

●Referral to a specialist for additional evaluation and management generally is warranted for children with specific diagnostic concerns (eg, spinal epidural abscess, inflammatory arthritis, vertebral infection, scoliosis, spondylolysis, spondylolisthesis, disc herniation, bone or spinal cord tumor). (See 'Indications for referral' above.)