What is the appropriate X-ray order and diagnostic code for a patient with left-sided back pain near the ribs, with a history of back injury in the thoracic and lumbar spine region?

Ordering X-ray for Left-Sided Thoracolumbar Back Pain with History of Injury

Order anteroposterior (AP) and lateral radiographs of both the thoracic spine and lumbar spine, with an additional "swimmer's lateral" view of the upper thoracic spine if the shoulders obscure this region. 1

Imaging Order Specifications

Standard Views Required

• Thoracic spine: AP and lateral views 1
• Lumbar spine: AP and lateral views 1
• Upper thoracic spine: Add swimmer's lateral view if T1-T4 region is obscured by shoulders 1

The American College of Radiology specifically recommends this combination when screening the thoracolumbar spine with radiographs, particularly when there is midline tenderness or history of injury in this region. 1, 2

Diagnostic Coding Options

Primary ICD-10 Codes to Consider

For pain with history of injury:

• M54.6 - Pain in thoracic spine
• M54.5 - Low back pain (if lumbar involvement)
• S23.9XXA - Sprain of unspecified parts of thorax, initial encounter (if acute injury suspected)
• S33.5XXA - Sprain of ligaments of lumbar spine, initial encounter (if lumbar injury suspected)

If fracture is suspected based on risk factors:

• M80.08XA - Age-related osteoporosis with current pathological fracture, vertebra(e), initial encounter (if patient >65 years or on chronic steroids) 3, 4

For old injury:

• M54.6 with Z87.81 (Personal history of (healed) traumatic fracture) 5

Clinical Decision Algorithm

When X-ray is Appropriate (Your Patient Fits Here)

History of back injury in the thoracolumbar region warrants imaging, especially with:

• Midline or paraspinal tenderness on examination 3, 2
• History of trauma to this specific area 3, 6
• Age >65 years (lower threshold for fracture) 3, 4
• Chronic steroid use 3, 4

Your patient has a history of back injury in this region, which is a red flag that justifies initial radiographic evaluation rather than waiting for conservative management to fail. 3, 2

Important Clinical Context

X-ray limitations you should know:

• Radiographs have only 49-62% sensitivity for thoracic spine fractures and 67-82% sensitivity for lumbar spine fractures 1
• CT has 94-100% sensitivity but is reserved for follow-up after abnormal X-ray findings or when higher suspicion exists 1
• If X-ray is negative but clinical suspicion remains high (persistent pain, risk factors present), proceed to MRI without contrast as the next step 2, 4

Red Flags Requiring Different Imaging Approach

If your patient has any of these, skip X-ray and order MRI without contrast instead:

• Neurologic deficits (myelopathy or radiculopathy signs) 1, 3, 2
• Progressive motor weakness 3
• Bowel/bladder dysfunction 3
• Saddle anesthesia 3

If suspecting malignancy or infection (fever, weight loss, history of cancer, immunosuppression), order MRI without and with contrast instead of X-ray. 3, 2, 4

Common Pitfalls to Avoid

Do not assume negative X-rays rule out fracture - MRI may still be needed if clinical suspicion persists, as radiographs miss a significant percentage of fractures, particularly in the thoracic spine. 1, 4

Do not delay imaging if neurologic symptoms develop at any point - this requires immediate MRI regardless of X-ray results. 3, 4

Do not order CT as initial study unless X-ray shows abnormality or patient has contraindication to other imaging - CT is complementary, not primary for this clinical scenario. 2

In elderly patients (>65 years), maintain lower threshold for proceeding to MRI even with negative X-rays, as they have high risk for compression fractures that may not be visible on plain films. 3, 4