Yes, obtain plain radiographs of the right femur
Even with a non-tender hip and pelvis, you should obtain plain radiographs of the right femur if there is a suspected femur injury. The absence of hip/pelvis tenderness does not exclude a femoral shaft or distal femur fracture, and plain radiographs remain the appropriate first-line imaging modality for suspected extremity fractures.
Clinical Reasoning
The key distinction here is anatomic: your patient has a non-tender hip/pelvis but a suspected right femur injury. These are separate anatomic regions requiring different imaging approaches:
- Hip/pelvis imaging (which the ACR guidelines address) focuses on proximal femoral and pelvic fractures 1
- Femur imaging targets the femoral shaft and distal femur, which are distinct from the hip region
The ACR Appropriateness Criteria emphasize that radiography is the initial imaging modality of choice for suspected fractures because it is rapidly obtained, well tolerated, and frequently sufficient for treatment planning 1. This principle applies to femoral shaft fractures just as it does to hip fractures.
Imaging Approach for Suspected Femur Injury
Obtain AP and lateral radiographs of the right femur that include:
- The knee joint distally
- Enough of the proximal femur to evaluate for extension toward the hip
Why radiographs first?
- High diagnostic yield: At least 90% of fractures are identified on initial radiographs 1
- Rapid and practical: Quickly obtained in the emergency or trauma setting
- Treatment planning: Often sufficient to guide immediate management without additional imaging 1
Important Caveats
If radiographs are negative but clinical suspicion persists:
The absence of tenderness in the hip/pelvis is actually reassuring for proximal femoral pathology, but if your clinical examination of the femur itself (thigh pain, inability to bear weight, mechanism of injury) suggests fracture despite negative radiographs:
- MRI without contrast is the gold standard for radiographically occult fractures, with 99-100% sensitivity 1
- CT scan is an alternative if MRI is unavailable, though less sensitive than MRI 1
Clinical pearl:
The ACR guidelines note that patients with suspected proximal femur fractures often have concomitant pelvic fractures 1. However, your patient's non-tender pelvis makes this less likely. Focus your imaging on the area of clinical concern—the femur—rather than obtaining unnecessary pelvic views if the pelvis is truly asymptomatic.
Pitfall to avoid:
Don't skip imaging based solely on the absence of hip/pelvis tenderness. Femoral shaft fractures can present with localized thigh findings while the hip remains non-tender. The mechanism of injury and specific location of symptoms should guide your imaging, not just the absence of proximal findings.