How to Order X-rays for Sciatica/Lower Back Pain
Plain radiographs (X-rays) of the lumbar spine are NOT routinely indicated for uncomplicated sciatica or low back pain and should only be ordered in specific clinical scenarios involving red flags or risk factors for structural pathology. 1, 2
When X-rays ARE Appropriate
High-Risk Patient Populations
- Patients with osteoporosis or chronic steroid use should receive initial evaluation with anteroposterior (AP) and lateral radiographs 1
- Elderly patients or those with suspected vertebral compression fracture warrant upright radiographs to assess axial loading and functional information 1
- History of trauma (even minor trauma) with suspected fracture requires radiographic evaluation 1, 3
Red Flag Clinical Scenarios
- History of cancer – the only red flag proven to increase probability of finding spinal malignancy 1
- Vertebral tenderness on examination correlates with higher diagnostic yield 3
- Age >50 years increases likelihood of significant pathology 3
Correct X-ray Views to Order
Order: "Lumbar spine, 2 views (AP and lateral)" 1
Key Technical Points
- Anteroposterior (AP) and lateral views are standard and sufficient 1
- Do NOT order oblique views – they double radiation dose without providing additional diagnostic information 1
- Upright/weight-bearing films provide functional information about axial loading 1
- Flexion and extension views can be added only if evaluating for spine instability 1
When X-rays Are NOT Appropriate
Skip X-rays entirely in these situations:
- Uncomplicated acute low back pain or sciatica without red flags – imaging does not improve outcomes 4, 2
- Radicular symptoms <6 weeks duration with normal neurological examination 4, 2
- Young patients without trauma, cancer history, or systemic symptoms 1, 2
What to Order Instead of X-rays
MRI is Preferred Over X-rays For:
- Radicular symptoms (sciatica) persisting >6 weeks despite conservative management in surgical candidates 4, 2
- Severe or progressive neurological deficits requiring immediate imaging 4, 5
- Suspected cauda equina syndrome (saddle anesthesia, bowel/bladder dysfunction) 4, 2
- Suspected infection, malignancy, or immunosuppression – MRI lumbar spine without and with IV contrast is superior 1
CT Scan Alternative:
- When MRI is delayed >2-4 weeks and patient has persistent radiculopathy requiring intervention, CT lumbar spine is reasonable 4
- CT has >80% sensitivity/specificity for most lumbar pathologies including stenosis 4
Common Pitfalls to Avoid
- Do not order X-rays for routine sciatica – radiographic findings (osteophytes, disc space narrowing) correlate poorly with symptoms and are present in asymptomatic individuals 6
- Do not delay appropriate MRI by ordering X-rays first in patients with red flags or neurological deficits 4, 5
- X-rays are insensitive to soft tissue pathology – they miss disc herniations, nerve root compression, and early infection/malignancy 1
- At least 50% of bone must be eroded before changes are visible on radiographs, making them inadequate for cancer screening 1
Clinical Documentation for Ordering
When X-rays ARE indicated, document:
- Specific risk factors (osteoporosis, steroid use, age >50, trauma history)
- Physical examination findings (vertebral tenderness, positive straight leg raise)
- Duration of symptoms and failed conservative treatments
- Rationale for structural evaluation versus soft tissue imaging
Bottom line: For typical sciatica, proceed directly to MRI after 6 weeks of conservative management if the patient is a surgical candidate, or order immediate MRI if red flags are present. Reserve X-rays only for patients with osteoporosis, steroid use, trauma, or age >50 with suspected compression fracture. 1, 4, 2