Subtrochanteric femur fracture’s most common deformity after antegrade nailing is varus and procurvatum (or flexion).

This is caused by the hip abductors (gluteus medius and gluteus minimus muscles), iliopsoas muscle and short external rotator muscles pulling the proximal fragment into abduction, flexion and external rotation respectively. While the distal fragment is pulled into adduction by the adductor muscles.

  • Subtrochanteric region typically defined as area from lesser trochanter to 5 cm distal.
  • Fractures with an associated intertrochanteric component may be called
    • Intertrochanteric fracture with subtrochanteric extension
    • Peritrochanteric fracture