Should I get an X-ray?

X-ray Imaging: When It's Appropriate and When It's Not

X-rays should be ordered only when clinically indicated for specific conditions, as they carry radiation exposure risks that must be weighed against potential diagnostic benefits. 1

Appropriate Indications for X-rays

Musculoskeletal Conditions

• Suspected fractures or trauma: X-rays are the first-line imaging modality for evaluating bone injuries 2
• Joint abnormalities: To assess alignment, degeneration, or hardware position 2
• Chronic hip pain: Radiographs should be obtained first in most cases before proceeding to more advanced imaging 2

Dental Conditions

• Suspected dental caries: Bitewing X-rays are the examination of choice for patients with suspected caries in primary or permanent teeth 2
• Dental infections: Intraoral X-rays are indicated when infection involving the pulp or apex is suspected 2
• Fistula evaluation: If a dental fistula is present, diagnosis requires intraoral radiograph with a gutta-percha cone inserted inside the fistula 2

Respiratory Conditions

• Suspected diaphragmatic hernia: In patients with respiratory symptoms, chest X-ray (both anteroposterior and lateral) is recommended as the first diagnostic study 2
• Suspected soft-tissue gas: X-ray is the preferred initial study (rated 9/9 for appropriateness) 2

Other Indications

• Suspected Charcot neuro-osteoarthropathy: Plain X-rays of the foot and ankle should be performed as initial imaging, ideally with bilateral views 2

When X-rays Should Be Avoided

• Routine admission chest X-rays: Studies show that routine chest X-rays on hospital admission rarely reveal clinically unsuspected findings and have minimal impact on patient care (only 3.87% of cases) 3
• Uncomplicated back pain without red flags: X-rays should not be ordered for nonspecific chronic low back pain in the absence of concerning symptoms 1
• Soft tissue pathology: MRI or ultrasound is generally more appropriate 2
• Screening without specific clinical indication: Routine X-rays without clear medical necessity expose patients to unnecessary radiation 4

Follow-up Imaging Considerations

If initial X-rays are negative or equivocal:

• For suspected stress fracture: MRI without contrast is the preferred next imaging study 1
• For suspected osteomyelitis: MRI without and with contrast is recommended 2
• For suspected active Charcot neuro-osteoarthropathy: MRI should be performed if plain X-rays appear normal 2

Radiation Safety Considerations

• The volume of medical imaging has led to a sixfold increase in annual per capita radiation exposure between 1980 and 2006 4
• It is estimated that 2% of future cancers will be caused by radiation from CT exposure 4
• The ALARA principle (As Low As Reasonably Achievable) should guide imaging decisions to minimize radiation exposure 1

Decision-Making Algorithm

1. Identify specific clinical question: What diagnosis are you trying to confirm or exclude?
2. Consider non-radiographic alternatives: Could the diagnosis be made clinically or with non-radiation imaging?
3. Assess risk-benefit ratio: Does the potential diagnostic benefit outweigh radiation exposure risk?
4. Select appropriate imaging modality: Is X-ray the best first-line test for this specific condition?
5. Consider patient factors: Age, pregnancy status, and previous radiation exposure may influence decision

Common Pitfalls to Avoid

• Ordering X-rays for defensive medicine or documentation purposes rather than clinical necessity 5
• Following "knee-jerk" tendencies to order radiographs for reassurance without clear indications 5
• Failing to consider radiation-free alternatives like ultrasound or MRI when appropriate 1
• Overlooking the cumulative radiation exposure from multiple imaging studies 4

Remember that X-ray imaging should be used to answer specific questions raised by history and physical examination, not as a routine screening tool in the absence of specific indications.