Use of the Medoff sliding plate for subtrochanteric hip fractures

To evaluate the effects of dynamization of a sliding hip screw plate on the fixation stability for several types of subtrochanteric fractures. Clinical results of treating reverse oblique fractures occasionally show medialization of the femoral shaft.

Two types of plate dynamization were compared using the same test protocol in identically prepared groups of uniform, artificial femurs.

Sawbones composite femurs (Pacific Research Labs, Vashon, WA) having five orientations of simulated subtrochanteric fractures were used with the Medoff plate (Medpac, Inc., Valencia, CA) either fully dynamized or with the sliding lag screw locked. These specimens were physiologically loaded and cycled and displacements of the proximal femur determined.

Significantly more shaft medialization occurred with reverse oblique fracture patterns when the Medoff plate was fully dynamized.

Clinical treatment of reverse oblique fractures with the Medoff plate should be performed using the lag screw locked and only the plate dynamized.