CT analysis of proximal femoral trabecular pattern simulating skeletal pathology

Fragility fractures of the proximal femur: review and update for radiologists

Proximal femoral fragility fractures are common and result in significant morbidity and mortality along with a considerable socioeconomic burden. The goals of this article are to review relevant proximal femoral anatomy together with imaging, classification, and management of proximal femoral fragility fractures, and their most common complications. Imaging plays an integral role in classification, management and follow-up of proximal femoral fragility fractures. Classification of proximal femoral fragility fractures is primarily based on anteroposterior hip radiographs. Pertinent imaging features for each category of proximal femoral fractures that would guide management are: differentiating nondisplaced from displaced femoral neck fractures, distinguishing stable from unstable intertrochanteric fractures, and determining the morphology and comminution of subtrochanteric fractures. Treatment of proximal femoral fragility fractures is primarily surgical with either arthroplasty or internal fixation. Intramedullary nailing is used in the treatment of some types of proximal femoral fragility fractures and may be associated with unique complications that become evident on postoperative follow-up radiographs.

Morphological analysis of the proximal femur using quantitative computed tomography

The anatomy of the proximal femur was studied in 35 specimens using quantitative computed tomography (QCT) and compared with anatomical sections studied by plane radiography and gross dissection. We found the primary supporting structure of the femoral head to be the primary compressive strut, which is a dense column of trabecular bone projecting from the pressure buttress of the medial femoral neck to the epiphyseal scar. Trabecular bone mushroomed from the epiphyseal scar and terminated at right angles to the cortex of the femoral head. We believe the primary compressive strut is the predominant load-bearing structure connecting the femoral head to the femoral neck, as many specimens lacked continuity of the head cortex to the femoral neck. Based on the CT number, the primary compressive strut had similar bone density to cortical structures such as the lesser trochanter, calcar femorale and posterior lateral femoral cortex. Ward's triangle lacked structural integrity in many cases, and we doubt the significance of tensile trabculae for sharing load. Surgical techniques such as femoral fracture fixation, resurfacing hip arthroplasty and allograft transplantation may benefit from this knowledge.