Authors of section

Authors

Derek Donegan, Michael Huo, Michael Leslie

Executive editor

Michael Baumgaertner

Open all credits

Adjunct plate options

1. Introduction

If there is no room for bicortical screw fixation, different options may be used around the femoral stem to secure the plate:

  • Unicortical locking screw fixation
  • Cerclage cables integrated into the plate
  • Locking attachment plate
  • Alternative plate systems
Note: Attachment plates require small fragment locking screw fixation.

2. Unicortical locking screw

Limited options are available for unicortical screws. These are often blunt tip screws that will abut the femoral stem. The addition of unicortical locking screws creates a length stable construct. These screws should not be used in isolation and must have either bicortical screws or cerclage fixation for adequate lasting stability.

Unicortical locking screw

3. Cerclage cables integrated into the plate

Cable anchoring devices are inserted into unused plate holes or the drive recess of screws. The cerclage cable can be passed through the anchor.

Cerclage buttons

Sit in screwhead recess to resist pullout of the screw plate construct.

Cerclage buttons

Cerclage positioning pins

Seat directly into empty plate hole to maintain position of the cable relative to the plate.

Cerclage positioning pins

Crimp positioning pins

Combine a cable crimp and positioning pin in one piece. They seat directly into locking holes to maintain the position of the cable relative to the plate.

Crimp positioning pins

4. Locking attachment plate

The arms on each side of the plate offer the possibility to avoid the prosthetic stem with 3.5 mm locking or cortex screws. The arms of the attachment plate are usually contoured. However, attention must be paid to the integrity of the locking threads in the plate.

Locking attachment plate

Connection screw

The locking attachment plate is secured to the plate through the connection screw.

The connection screw consists of two parts:

  • Upper part
  • Conical part
Connection screw

Screw the conical part to the plate with a torque-limiting screwdriver.

Screw the conical part to the plate

Option: locking attachment plate prebending

The locking attachment plate can be prebent with a bending pin to adapt to the femur anatomy.

Locking attachment plate prebending

Locking attachment plate positioning

The locking attachment plate is positioned over the selected plate hole and secured into the conical part with the upper part.

Drill sleeves can be screwed in to be used as handles.

Implants position is verified under image intensification.

Locking attachment plate positioning

A screw hole is drilled with a drill bit. The hole direction should be checked with image intensification.

A screw hole is drilled with a drill bit

3.5 mm locking screw is inserted and screwed in the prepared hole.

3.5 mm locking screw is inserted and screwed

The locking attachment plate is stabilized with additional locking screws.

Additional locking screws

5. Alternative plate systems

Many different plate designs exist. Some plates offer multiple screw options at each level, utilizing a wider plate.

Alternative plate options

In addition, variable angle screw fixation can provide greater access to intact bone. This can be done by placing a cortex screw that is converted to a locking screw with a locking cap in some systems. Other plating systems have variability in the locking mechanism that can be used to create a locked screw in a nonstandard plane.

Variable angle screw fixation

Screw diameter can also be variable within the same plate hole.

Screw diameter can be variable

Addition of greater trochanteric specific plate and screw stabilization can be integrated into standard plates.

greater trochanteric specific plate