Authors of section

Author

Tomas Guerrero

Executive Editor

Amy Kapatkin

General Editor

Noel Moens

Open all credits

Plate fixation with lag screws and pins

1. Principles

Reducible A3 fractures should be anatomically reduced with lag screws to reconstruct the bone column. Pins may be used to provide temporary stabilization.

A plate is used in a neutralization fashion.

Note: If anatomical reconstruction cannot be accomplished, a bridging technique should be used.

Read more about lag screw fixation.

31 A3

2. Patient positioning

This procedure is performed with the patient in lateral recumbency.

lateral recumbency position

3. Approach

A craniolateral approach is performed in combination with the lateral approach to the femoral shaft.

The length of the incision will depend on the extent of the fracture.

lag screw and k wire

4. Surgical technique

Reduction

The main fracture fragments are reduced with the help of bone holding forceps, starting from proximal to distal.

plate fixation with lag screws and pins

Preliminary fixation

K-wires or bone holding forceps may be used to provide temporary stabilization.

plate fixation with lag screws and pins

Fixation of the fragments

The fragments are secured with lag or position screws.

plate fixation with lag screws and pins

Plate selection

The plate is perfectly contoured over the lateral aspect of the greater trochanter to allow placement of at least three screws in the proximal fragment.

Read more about plate preparation.

plate fixation with lag screws and pins

Plate placement

The plate is positioned as proximal as possible to maximize the number of screws in the short proximal fragments.

plate fixation with lag screws and pins

Plate application

Following contouring, the plate is applied to the lateral surface of the reconstructed bone.

The plate position and contouring to the bone is checked thoroughly, and adjusted if required.

plate fixation with lag screws and pins

Plate fixation

The plate is fixed in a neutralization fashion. The first screw is inserted in the second or third plate hole engaging the femoral neck and head. The largest diameter screw that will fit the plate should be used for that purpose.

plate fixation with lag screws and pins

A second neutral screw is inserted on the distal part of the bone.

plate fixation with lag screws and pins

Additional lag screws may be inserted through the plate holes where needed. All remaining plate screws are inserted in a neutral mode.

plate fixation with lag screws and pins

Validation of fixation

Postoperative orthogonal radiographs are taken to assess fixation.

31 A3

Fixation with a locking plate

If a locking plate is used, only 2-3 locking bicortical screws are needed per main fragment. One advantage of using a locking plate is that precise contouring to the surface of the bone is not necessary; however, contouring and perfect positioning is required to ensure that the screws adequately engage the femoral neck and head as the orientation of the screws is dictated by the plate and cannot be altered.

Note: If a combination of cortex and locking screws is used, the plate must be anatomically contoured at the sites of non-locking screw insertion. The cortex screws must be inserted and tightened before any locking screws are placed.

plate fixation with lag screws and pins

5. Case example A3

4-year-old Corgi with an A3 fracture from being hit by a car.

definition

The fracture was repaired using a 9 hole 2.7mm LCP with locking screws.

plate fixation with lag screws and pins

Postoperative radiographs at 4 months.

plate fixation with lag screws and pins

Postoperative radiographs at 6 months.

plate fixation with lag screws and pins

Postoperative radiographs at 9 months.

plate fixation with lag screws and pins

6. Aftercare

Activity restriction is indicated until evidence of bone union is detected on radiographic examinations.

Implants may cause discomfort of the adjacent soft tissue. If this occurs, implants are removed after radiographic evidence of bone healing is complete. In case of infection, implants must be removed after complete bone healing.

Phase 1: 1-3 day after surgery

Aim is to reduce the edema, inflammation, and pain.

Integrative medical therapies, anti-inflammatory and analgesic medications.

Phase 2: 4-10 days after surgery

Aim is to resolve the hematoma, edema and control pain, and prevent muscle contracture.

Anti-inflammatory and analgesic medications may still be needed. Rehabilitation and integrative medical therapies can be used.

Special attention should be given to patients less than 1 year of age with a femoral fracture. Rehabilitation is strongly recommended to help prevent quadriceps muscle contracture.

If the dog is not starting to use the limb within a few days after surgery, a careful evaluation is recommended.

10-14 days after surgery the sutures are removed.

Radiographic assessment is performed every 4-8 weeks until complete bone healing is confirmed.

Implant removal

If there is no implant failure or infection, there is no need for implant removal.