Management of Negative Initial X-ray After FOOSH Injury
For patients with a FOOSH injury and negative initial radiographs but persistent clinical suspicion for fracture, you should proceed directly to MRI without IV contrast rather than repeating radiographs in 10-14 days, as this prevents delayed diagnosis and unnecessary immobilization. 1
Rationale for Advanced Imaging Over Repeat Radiography
The traditional approach of casting and repeating radiographs in 10-14 days has significant drawbacks:
Delayed diagnosis increases morbidity: While repeat radiographs at 10-14 days have increased sensitivity compared to initial films, this approach results in unnecessary immobilization of the vast majority of patients who do not have fractures, leading to loss of productivity and functional impairment 1, 2
MRI is superior for definitive diagnosis: MRI without IV contrast has excellent sensitivity for detecting occult fractures of the distal radius and carpal bones (particularly scaphoid) and can change diagnosis in 55% of patients and management in 66% of patients when initial radiographs are normal but clinical suspicion remains high 1
Prevents complications from missed fractures: Certain high-risk fractures (scaphoid, carpal bones) can lead to nonunion, avascular necrosis, and long-term disability if diagnosis is delayed 1, 2, 3
Clinical Decision Algorithm
High-Risk Patients (Proceed Directly to MRI):
- High-demand or manually working patients where timely diagnosis is medically and socioeconomically important 3
- Athletes or young active individuals 4
- Clinical examination findings suggesting scaphoid fracture (anatomic snuffbox tenderness, scaphoid tubercle tenderness) despite negative radiographs 2, 3
- Suspected intra-articular involvement or ligamentous injury 1
Alternative Approach (Cast and Repeat X-ray in 10-14 Days):
- Low-demand patients (e.g., retired individuals with minimal manual requirements) 3
- Limited access to advanced imaging
- Important caveat: Even in this group, 76% will be unnecessarily immobilized for an average of 30 days 2
CT Without IV Contrast as Alternative:
- When MRI is contraindicated or unavailable 1
- Particularly useful for confirming or excluding suspected wrist fractures when radiographs are equivocal 1
- Shows intra-articular extension of distal radius fractures more frequently than radiography 1
- Limitation: Cannot evaluate concomitant ligamentous injuries unlike MRI 1
Common Pitfalls to Avoid
Inadequate initial radiographic views: A minimum of 3 views is necessary for wrist evaluation (posteroanterior, lateral, and 45° semipronated oblique); 2-view examinations are inadequate for detecting fractures 1, 5
Assuming negative radiographs rule out fracture: Scaphoid fractures are overlooked in 20-40% of cases on initial radiographs 3
Prolonged empiric immobilization: The dogmatic approach of casting all "clinical scaphoid fractures" with negative radiographs results in unnecessary treatment in the vast majority (94% in one study had no fracture) 2
Missing non-FOOSH mechanisms: Scaphoid and other carpal fractures can occur without typical FOOSH mechanism and even without initial scaphoid tenderness 4
Overlooking associated injuries: Perilunate and lunate dislocations can be easily missed on initial assessment and require careful evaluation of lateral wrist radiographs 6
Summary of Imaging Modality Selection
MRI without IV contrast is the preferred next study after negative initial radiographs because it:
- Detects occult fractures with excellent sensitivity 1
- Evaluates concomitant ligamentous injuries 1
- Prevents delayed diagnosis and unnecessary immobilization 1, 2
- Does not require waiting 10-14 days for bone reaction to become visible 1
Repeat radiography at 10-14 days should be reserved only for low-demand patients with limited access to advanced imaging, recognizing this approach will unnecessarily immobilize most patients who do not have fractures 1, 2, 3