Fig. 2. The radiographs in included studies. (A) Normal bony structure of the proximal femoral head. The intertrochanteric line is shown in black and the line of the basicervical fracture in white. (B) Schematic figure depicting a radiograph in the study of Watson et al.⁷⁾. The fracture line started in the inferior area of the intertrochanteric line (black arrow). (C) Schematic figure showed the radiograph in study of Massoud.³⁾ The fracture line crossed the intertrochanteric line (black arrow). (D) Schematic figure depicting the radiograph in the study of Davis et al.¹²⁾ The lesser trochanteric area was involved in the fracture (black arrow). (E) Schematic figure depicting the radiograph in the study of Kuokkanen.¹³⁾ Fracture involved the greater trochanter (black arrow). (F) Schematic figure depicting the radiograph in the study of Su et al.¹¹⁾. The inferior area of the fracture line involved the intertrochanteric line (black arrow). Fractures not matching the definition of basicervical fracture.