ORIF - Bridge plating (Locking plate)

Throughout this treatment option illustrations of generic fracture patterns are shown, as four different types:

A) Unreduced fracture

B) Reduced fracture

C) Fracture reduced and fixed provisionally

D) Fracture fixed definitively

Bridge plating uses the plate as an extramedullary splint, fixed to the two main fragments, leaving the intermediate fracture zone untouched. Anatomical reduction of intermediate fragments is not necessary. Furthermore, their direct manipulation would risk disturbing their blood supply. If the soft tissue attachments are preserved, and the fragments are relatively well aligned, healing is enhanced.

Alignment of the main shaft fragments can be achieved indirectly with the use of traction and the support of indirect reduction tools, or indirectly via the implant.

Mechanical stability, provided by the bridging plate, is adequate for gentle functional rehabilitation and results in satisfactory indirect healing (callus formation). Occasionally, a larger wedge fragment needs to be approximated to the main fragments with a lag screw.

• Basic technique: insertion of cortical lag screws

It is important to restore axial alignment, length, and rotation.

Reduction can be performed with a single reduction tool (eg, large distractor) or by combining several steps (for example fracture table +/- external fixator, +/- reduction via the implant, etc.) to achieve the final reduction.

The preferred method depends on the fracture and soft-tissue injury patterns, the chosen fixation device, and the experience and skills of the surgeon.

If a large fragment has separated from the fracture and impaled the adjacent muscle, direct reduction may be required through a separate limited approach.

The patient may be placed in one of the following positions:

• Supine position with manual traction
• Lateral decubitus position
• Supine knee flexed 30°
• Scissor position

For this procedure a MIO approach is used.

Subtrochanteric fractures present a particular problem in terms of fracture reduction and alignment. Due to the strong pull of the iliopsoas muscle, the proximal fragment is flexed and externally rotated and therefore difficult to control.

Preliminary reduction should be undertaken before the plate is applied. Once the plate is attached to the proximal fragment the definitive reduction with respect to length, rotation and axis can then be achieved.

Reduction clamps are often required to achieve proper alignment. Pointed reduction forceps may be used, but may not provide enough force.

After the placement of two pins - one in the greater trochanter and the second one in the shaft - the large distractor is attached.

Attention has to be paid so that the pins do not conflict with the later plate position.

The preliminary reduction is held by tightening the clamps of the large distractor.

AO teaching video: Application of the large distractor

A dedicated locking plate, pre-shaped for the proximal femur, is the implant of choice for this technique.

Depending on the extent of the zone of fracture comminution and the underlying bone stock (osteoporosis), the appropriate plate length is chosen. Sufficient bicortical screws (a minimum of three up to six) should be inserted in each fracture fragment. The relative stability results from leaving plate holes empty over the fracture zone.

The proximal femoral plate is anatomically shaped to match the profile of the upper femur. First, the plate is adjusted optimally to fit the proximal fragment. Through the two attached wire guides, the proximal 2.5 mm guide wires are inserted into the proximal fragment.

The positions of the guide wires are verified under image intensification in both planes (AP and lateral).

The correct screw lengths are determined by measuring the remaining guide wire length, using the dedicated measuring device.

Cannulated 7.3 mm screws (locking or non-locking) are inserted over the guide wires into the proximal fragment.

Under image intensifier control, the preliminary reduction is again checked in respect to axial alignment and length and, to a degree the rotation (in more complex fractures the clinical judgment of the rotation becomes more important while the radiological findings in that respect is challenging to interpret).

Two blunt Hohmann retractors placed ventrally and dorsally around the femoral shaft can help to control the lateral position of the plate.

If the overall reduction is found to be satisfactory, the first cortical non-locking screw in the distal fragment is inserted. This screw helps to reduce the bone to the anatomically shaped implant. Nevertheless, this screw should not fully be tightened, still allowing fine tuning of the plate position on the lateral surface of the femur.

In case the lateral position, prior to the placement of the second screw, is not correct the use of sterile bolsters is helpful.

Once the most distal screw has been inserted, the first screw is now fully tightened.

In case the lateral position, prior to the placement of the second screw, is not correct the use of sterile bolsters is helpful.

In case of osteoporotic bone the usage of bi-cortical locking screws is advantageous.

In accordance with preoperative planning, additional screws are inserted into the proximal and distal main fragments.

Close monitoring of the femoral muscle compartments should be carried out especially during the first 48 hours, in order to rule out compartment syndrome.

In all cases in which radiological control has not been used during the procedure, a check x-ray to determine the correct placement of the implant and fracture reduction should be taken within 24 hours.

Unless there are other injuries or complications, mobilization may be started on postoperative day 1. Static quadriceps exercises with passive range of motion of the knee should be encouraged. If a continuous passive motion device is used, this must be discontinued at regular intervals for the essential static muscle exercises. Afterwards special emphasis should be placed on active knee and hip movement.

Full weight bearing may be performed with crutches or a walker.

Wound healing should be assessed regularly within the first two weeks. Subsequently a 6 and 12 week clinical and radiological follow-up is usually made. A longer period may be required if the fracture healing is delayed.

Implant removal is not mandatory and should be discussed with the patient, if there are implant-related symptoms after consolidated fracture healing.