Double plating
1. Introduction
Double plating should be used when a bridging plate alone is not strong enough to withstand the weight-bearing forces during healing. Double plating is also indicated when the main fragments are too short to get a stable fixation with one plate.
Locking screws give more stability than cortical screws. However, with cortical screws, the screw direction can be adapted to the other plate and the bone configuration. When using cortical screws, the contouring of the plate must be more exact.
In more distal fractures, the plates are applied to the medial and lateral surface of the bone. In more proximal fractures, they can be applied to the cranial and lateral surfaces.
2. Positioning and approach
Distal fractures
The positioning and approach depend on the fracture location.
A combination of a lateral approach and a medial approach may be necessary for more distal fractures. The patient should be placed in dorsal recumbency.
Proximal fractures
Both plates can be applied through a lateral approach extended cranially for more proximal fractures. The patient should be placed in lateral recumbency.
3. Reduction
Indirect reduction is achieved by distracting and aligning the major bone segments using bone-holding forceps or other distraction techniques.
4. First plate
Plate selection
The first plate to be applied should be relatively large and long. The length of the plate should allow the placement of at least three screws in each major fragment.
The first plate should preferably be applied to the medial surface for midshaft and distal fractures.
For proximal fractures, the first plate is applied to the lateral surface.
A locking plate is preferred to a plate with just cortical screws.
Plate preparation
The plate is contoured to the shape of the bone. Precise contouring is not as important when using locking plates.
Read more about plate preparation.
Temporary stabilization
If possible, the plate is secured to the bone with bone clamps or bone-holding forceps.
Plate application
5. Second plate
Plate selection
Depending on the stability of the first plate, the second plate can often be smaller.
The second plate is preferably applied on the lateral surface for midshaft and more distal fractures.
The second plate is most often applied on the cranial surface for proximal fractures.
Additional approach
For more distal fractures, two separate approaches are required. For the second plate, a lateral approach is used.
For proximal fractures, the lateral approach is extended cranially by moving the brachiocephalic muscle more medial or lateral for fixing the plate on the cranial surface of the humerus.
Plate preparation
The plate is contoured to the bone.
Note: If using cortical screws, the contouring of the plate must be more exact.
Plate application
The second plate should be positioned so that the holes are between the holes of the first plate. In this way, the screws from the two plates do not interfere with each other.
2–3 screws are inserted in each major fragment.
The screw holes in the plates can be on the same level when using two plates, leading to interference between two screws from different pates.
If locking screws are used, the interference can be avoided by using one monocortical screw. Alternatively, with cortical screws, interference can be avoided by angling the two screws away from each other.
6. Case example
Case example 1
1.5-year-old Domestic short-haired cat with a 12-C3 fracture.
The fracture was treated with double plating.
Follow-up radiographs were taken six months after surgery.
Case example 2
7-year-old dog with a 12-B1 fracture.
The fracture was treated with double plating.
7. Aftercare
Phase 1: 1–3 days after surgery
The aim is to reduce edema, inflammation, and pain.
Integrative medical therapies, anti-inflammatory medication, and analgesics are recommended.
For the first few days, a well-padded bandage on the whole leg helps to reduce edema and swelling of the distal limb.
Note: Animals carry 2/3 of their weight on the front limb. Therefore, strict leash confinement or cage rest and no jumping are recommended until radiographs show signs of bone healing.
Phase 2: 4–10 days after surgery
The aim is to resolve hematoma and edema and control pain.
Anti-inflammatory and analgesic medications may still be needed. Rehabilitation and integrative medical therapies can be used.
Passive movement of the elbow joint should be started early, not to lose range of motion.
A careful evaluation is recommended if the dog does not start to use the limb within a few days after surgery.
Early ambulation is aimed for.
Radial nerve neurapraxia may occur in some cases. This neurapraxia usually resolves within a few days.
Phase 3: > 10 days after surgery
10-14 days after surgery, the sutures are removed.
Radiographic assessment is performed every 4–8 weeks until bone healing is confirmed.
