What is the appropriate evaluation, imaging, and management for a patient presenting with back and hip pain after a fall?

Evaluation and Management of Back and Hip Pain After a Fall

Initial Imaging Protocol

Obtain an anteroposterior (AP) view of the pelvis with a cross-table lateral view of the symptomatic hip immediately as your first-line imaging. 1, 2 This combined approach is critical because patients with suspected hip fractures frequently have concomitant pelvic fractures (including sacrum and pubic rami), and the pelvis view allows comparison with the contralateral side for accurate diagnosis. 2

Key imaging specifications:

• AP pelvis view: Position with approximately 15 degrees of internal hip rotation 2
• Cross-table lateral view: Of the symptomatic hip to provide orthogonal views 2
• Rationale: Radiographs identify approximately 90% of proximal femoral fractures, but 10% remain occult on initial imaging 1, 2

When Initial Radiographs Are Negative

If radiographs are negative but clinical suspicion remains high, proceed directly to MRI of the pelvis and affected hip without IV contrast. 1, 2 This is non-negotiable for ruling out occult fractures.

Why MRI is superior:

• Sensitivity: 99-100% for proximal femoral fractures versus CT's significantly lower accuracy 2
• Additional diagnostic value: Detects concomitant pelvic fractures (38% of cases), soft tissue injuries, and accurately characterizes fracture morphology to guide surgical versus conservative management 1, 2
• Clinical impact: A negative MRI allows confident discharge from the emergency department, while rapid diagnosis reduces surgical delays beyond 12 hours, which significantly increases 30-day mortality risk 2

CT is explicitly inferior:

• Use CT only as a problem-solving modality after fracture identification on radiographs when you need better characterization of fracture morphology for surgical planning 1, 2
• CT limitations: Not as sensitive as MRI, with significant diagnostic failures and high inter-observer variability 2
• Limited advantages: Faster acquisition and usability in patients with severe confusion or MRI contraindications 2

Clinical Presentation Pitfalls

High-risk presentations requiring imaging even without classic findings:

• Atypical pain patterns: Patients may present with only vague buttock, knee, thigh, groin, or back pain without localized hip pain 3
• Preserved ambulation: Some patients with hip fractures can still walk, making diagnosis challenging 3
• Vertebral compression fractures: Back pain after a fall may represent vertebral compression fracture, particularly if pain radiates to flanks (66% of cases) or occurs spontaneously in bed (30% of cases) 4

Red flags demanding immediate advanced imaging:

• Age >65 years with nonspecific leg discomfort and difficulty bearing weight, even without documented trauma 3
• Worsening pain over 2-3 days after initial negative radiographs—this pattern was demonstrated in AAOS case studies where MRI revealed displaced basicervical femoral neck fractures 1
• Pain with internal/external hip rotation on examination, even with negative initial radiographs 1

Diagnostic Algorithm for Back Pain Component

For isolated back pain after a fall, obtain thoracic and lumbar spine radiographs initially. 4 If negative but clinical suspicion persists:

• MRI spine without contrast is the modality of choice to determine if vertebral compression fracture is acute versus chronic and to evaluate for malignant causes or neurological compromise 5
• Bone scanning may be necessary if immediate radiographs are normal, though this has largely been replaced by MRI 4
• Common mistake: Pain location and fracture site may not coincide—certain vertebrae (T8, T12, L1, L4) are more likely to fracture 4

Critical Timing Considerations

Delays in diagnosis and treatment are associated with increased mortality, complication rates, length of hospital stay, and costs. 2, 6 Specifically:

• Surgical delays >12 hours significantly increase 30-day mortality risk in hip fracture patients over 50 years 6
• Diagnostic delays averaged 4.5 days in one study when vertebral compression fractures were missed initially 4

Common Pitfalls to Avoid

• Never rely solely on hip radiographs without pelvis views—you will miss associated pelvic fractures that alter treatment decisions 2
• Never use ultrasound as primary imaging for hip fracture detection—it has only 65% specificity despite 100% sensitivity for joint effusion 1, 7
• Never assume negative radiographs exclude fracture in high-risk patients—proceed to MRI without delay 2
• Never order bone scan as second-line imaging when MRI is available—bone scans can be falsely negative for up to 72 hours and have been superseded by MRI 1

Management Priorities

Immediate actions while awaiting imaging:

• Immobilize in position found to reduce pain and prevent further injury 6
• Multimodal analgesia: Regular IV acetaminophen, NSAIDs, and opioids as needed with regular pain reassessment 6
• Assess for vascular compromise immediately—blue, purple, or pale extremity requires emergency activation 6

Post-diagnosis management:

• Hip fractures: Surgical intervention within 12 hours when indicated, with VTE prophylaxis for 4 weeks postoperatively (moderate to strong evidence) 1
• Vertebral compression fractures: Acetaminophen, NSAIDs, narcotics, calcitonin, limited bed rest, bracing, physical therapy; consider vertebroplasty/kyphoplasty for inadequate pain relief 8, 5