Management of Suspected Scaphoid Fracture with Negative Initial Radiographs
The APN should proceed directly to MRI without IV contrast (or CT without contrast if MRI is unavailable) rather than empirically immobilizing the patient in a cast, as advanced imaging immediately identifies occult fractures and prevents unnecessary immobilization in the majority of patients who do not have fractures. 1
Rationale for Immediate Advanced Imaging
The traditional approach of empiric cast immobilization followed by repeat radiographs in 10-14 days results in 76-94% of patients being unnecessarily immobilized for an average of 30 days, leading to significant loss of productivity when most do not have fractures. 2, 3 The American College of Radiology specifically recommends proceeding directly to MRI or CT without contrast when initial radiographs are negative but clinical suspicion remains high, rather than using empiric casting. 1
Preferred Imaging Modality
MRI without IV contrast is the preferred next study, with high sensitivity for occult fractures through detection of bone marrow edema, and the added benefit of detecting concomitant soft tissue injuries including scapholunate ligament tears that may affect treatment decisions. 1, 4
CT without IV contrast is an acceptable alternative with superior visualization of bone cortex and trabeculae, shorter acquisition times than MRI, and is particularly useful for preoperative planning to determine fracture location and fragment displacement. 1, 4
Bone scintigraphy is a reasonable alternative if MRI/CT is unavailable, though it has lower specificity due to uptake from bone contusions and osteoarthritis. 1
Clinical Examination Findings to Document
While awaiting imaging, the APN should document specific clinical findings that predict fracture risk:
- Anatomic snuffbox tenderness (sensitivity 85.71%, specificity 29.62%) 3
- Scaphoid tubercle tenderness (sensitivity 95.23%, specificity 74.07%) - the most reliable single clinical test 3
- Painful axial thumb compression 5
- Painful ulnar deviation 5
- Swelling of the anatomic snuffbox 5
Temporary Management Pending Imaging
If advanced imaging cannot be obtained within 24-48 hours, temporary thumb spica splint immobilization is reasonable until imaging is completed. 6 However, the goal should be same-day or next-day advanced imaging to avoid prolonged unnecessary immobilization. 2
Assessment for High-Risk Features
The APN should evaluate for features suggesting unstable fracture patterns that would require orthopedic referral:
- Displacement >1-2 mm on any radiographic view 1
- Scapholunate angle abnormalities or scapholunate diastasis >4 mm 1
- Dorsal tilt of lunate >10° 1
- Proximal pole involvement (higher risk for avascular necrosis and non-union) 1, 4
Common Pitfalls to Avoid
Do not rely on repeat radiographs in 10-14 days as the primary diagnostic strategy, as this approach unnecessarily immobilizes 76-94% of patients who do not have fractures. 2, 3
Do not assume negative initial radiographs exclude fracture - up to 25% of scaphoid fractures are radiographically occult initially. 4, 6
Ensure adequate initial radiographic views were obtained (minimum 3 views: posteroanterior, lateral, and 45° semipronated oblique "scaphoid view") before concluding radiographs are truly negative. 1