Diagnostic Imaging
Table 2. Suggestions for Imaging in Patients with Acute LBP
Imaging Action and Clinical
Situation
Suggestions for Initial Imaging
Immediate Imaging
Radiography plus
erythrocyte sedimentation
ratea
>> Major risk factors for cancer (new onset of LBP with
history of cancer, multiple risk factors for cancer, or
strong clinical suspicion for cancer)
MRI
>> Risk factors for spinal infection (new onset of LBP
with fever and history of intravenous drug use or
recent infection)
>> Risk factors for or signs of the cauda equina
syndrome (new urine retention, fecal incontinence,
or saddle anesthesia)
>> Severe neurologic deficits (progressive motor
weakness or motor deficits at multiple neurologic
levels)
Defer Imaging After a Trial Therapy
Radiography with or without
erythrocyte sedimentation
ratea
>> Weaker risk factors for cancer (unexplained weight
loss or age > 50 y)
>> Risk factors for or signs of ankylosing spondylitis
(morning stiffness that improves with exercise,
alternating buttock pain, awakening because of back
pain during the second part of the night, or younger
age [20 to 40 y])
>> Risk factors for vertebral compression fracture
(history of osteoporosis, use of corticosteroids,
significant trauma, or older age
[> 65 y for men or > 75 y for women]
MRI
>> Signs and symptoms of radiculopathy (back
pain with leg pain in an L4, L5, or S1 nerve root
distribution or positive result on straight leg raise
or crossed straight leg raise test) in patients who are
candidates for surgery or epidural steroid injection
>> Risk factors for or symptoms of spinal stenosis
(radiating leg pain, older age, or pseudoclaudication)
in patients who are candidates for surgery
No Imaging
>> No criteria for immediate imaging and back pain
improved or resolved after a 1-mo trial of therapy
>> Previous spinal imaging with no change in clinical
status
a
4
Consider MRI if the initial imaging result is negative but a high degree of clinical suspicion for cancer
remains.
