Pertrochanteric Fracture Fixation In Elderly Adults Using Proximal Femoral Nail Anti-rotation (HERACLES) With a T-shaped Parallel Blade: A New Design

The trochanteric area is defined by AO as the area bordered by the tip of the greater trochanter, extracapsular portion of the femoral neck extending to a line parallel to the inferior most border of the lesser trochanter.

Pertrochanteric fracture is a fracture is of the trochanteric area which is usually reducible. Unstable pertrochanteric fracture is defined as AO-31A2 or AO-31A3. Instability arises from the degree of comminution, the presence, and comminution of the posteromedial fragment and lastly, lateral wall involvement The ideal implant for fixation of this kind of fractures is still under debate, but intramedullary implants are preferred than extramedullary implants in these unstable fractures. On the other hand, unique fracture configurations predispose to instability such as reverse obliquity fractures and fractures extending to the subtrochanteric area.

Proximal femoral locking plate as used in unstable pertrochanteric fracture has a high complication rate. In one study in 2014, there is up to 41.4% failure rate due to the proud plate, screw malposition, too rigid construct when used as a bridge plate.

Intramedullary implants specifically cephalomedullary nails has been the mainstay of treatment in unstable pertrochanteric fractures primarily because of the short moment arm and load-sharing properties. It employs relative stability and can be applied in a minimally invasive manner.

In 1997, the AO/ASIF group developed the proximal femoral nail. The proximal femoral nail has two proximal screws that traverse the neck to the femoral head. The inferior screw is the load-bearing screw, and the superior screw is the anti-rotation screw. Good to excellent results were observed using this implant compared to previous implant designs, but complications still exist.