Review Question - QID 214673

Ipsilateral femoral neck fractures are present in up to 9% of patients with femoral shaft fractures sustained from high-energy trauma. Evaluation of the femoral neck with fine-cut (2-mm) computed tomography (CT) imaging significantly improves the ability to diagnose occult fractures.

Ipsilateral femoral shaft and neck fractures often occur in young adults after high-energy trauma. Femoral neck fractures are frequently vertically oriented and commonly missed due to minimal or no displacement. Not recognizing this injury can result in displacement, nonunion, and osteonecrosis. Protocols used to prevent missed injuries include dedicated internal rotation hip radiographs, CT imaging with 2-mm cuts, and intraoperative fluoroscopic examination.

Yang et al. reported on the role of CT in the diagnosis of ipsilateral femoral neck fractures in patients undergoing intramedullary nail fixation for shaft fractures. In a series of 152 femoral shaft fractures, the authors found 14 femoral neck fractures that were not visible on initial pelvic radiographs. The authors recommend preoperative CT scans of the femoral neck in high-risk patients such as those with associated fractures of the acetabulum, distal femur, or patella.

Tornetta et al. evaluated the diagnosis of femoral neck fractures in patients with femoral shaft fractures after the establishment of a diagnostic protocol. The protocol consisted of preoperative AP internal rotation plain radiographs and a fine (2-mm) cut CT scan; an intraoperative fluoroscopic lateral radiograph prior to fixation; and postoperative AP and lateral radiographs prior to emergence from anesthesia. The authors note that the protocol reduced the delay in diagnosis by 91%. They conclude the evaluation of the femoral neck with fine-cut CT and dedicated internal rotation hip radiographs significantly improves the ability to diagnose an associated femoral neck fracture.

Jones et al. reviewed the diagnosis and management of ipsilateral femoral neck and shaft fractures. The authors note that up to 9% of patients with femoral shaft fractures will have a femoral neck fracture. Establishing protocols for diagnosis and management can help prevent missed injuries and complications. The authors conclude that prophylactic femoral neck fixation should be considered in patients at high risk for a non-displaced neck fracture.

Figures A demonstrates a comminuted diaphyseal femur fracture.

Incorrect Answers
Answer 1: Ten degrees of INTERNAL rotation places the femoral neck in profile on the AP radiograph and improves the ability to diagnosis ipsilateral femoral neck fractures.
Answer 2: Traction radiographs can be used to assess displaced femoral neck fractures, but are not used to evaluate for occult fractures.
Answer 4: Bone scans can be considered in cases of possible stress or insufficiency fractures of the femoral neck, but are not typically used for patients with traumatic femoral shaft fractures.
Answer 5: A CT scan with 2-mm cuts should be considered to ensure a non-displaced femoral neck fracture is not present.