Patterns and research progress on the concomitant ipsilateral fractures of intracapsular femoral neck and extracapsular trochanter

Objective To summarize the patterns and research progress of the concomitant ipsilateral fractures of intracapsular femoral neck and extracapsular trochanter, and to provide a common language among orthopedic surgeons for scientific exchange. Methods According to related literature and authors own experiences concerning the anatomic border between femoral neck and trochanter region, the intertrochanteric line (or intertrochanteric belt) and its capsularligament attachment footprint, fracture patterns, and treatment strategies were reviewed and analyzed. Results With the rapid growing of geriatric hip fractures, an increased incidence was noted in recent years regarding the proximal femoral comminuted fractures that involving ipsilateral intracapsular neck and extracapsular trochanter regions simultaneously. But the concept of femoral neck combined with trochanter fractures was ambiguous. Based on the anatomic type of femoral neck fracture, the location of fracture center, and the ability to achieve direct inferior calcar or anteromedial cortex-to-cortex apposition and buttress, we classified these complex fractures into 3 sub-types: ① Segmental femoral neck fractures (two separate fracture centers at subcapital and trochanteric region respectively); ② Femoral neck fracture (trans-cervical) with extension to the supero-lateral trochanteric region (fracture center in femoral neck); ③ Trochanteric fracture with extension to the medio-inferior femoral neck region (fracture center in trochanter, comminuted basicervical fracture, or variant type of comminuted trochanter fracture). For treatment strategy, surgeons should consider the unique characteristics of femoral neck and trochanter, usually with combined fixation techniques, or arthroplasty supplemented with fixation. Conclusion Currently there is no consensus on diagnosis and terminology regarding the concomitant ipsilateral fractures of femoral neck and trochanter. Further studies are needed.