A condylar blade plate is designed for fractures near the joint and as the blade is part of the plate, compression of a periarticular fracture is possible if the plate has a compression hole.
Principle
The blade on the condylar blade plate is an integral part of the plate which allows for transmission of forces applied across the blade to be fixed to the side of the shaft of bone. This permits axial loading and rigidity.
Special features of the condylar plate:
- The additional hole adjacent to the blade can be used for a screw so that condylar fracture fragments can be compressed together transversely using the lag screw principle.
- In addition to this, screws can be placed eccentrically in a plate to allow compression between the blade and the shaft if the plate design allows for this.
Note: Medartis blade plates don’t, but other fragment sets may offer this feature.
Tip: A similar effect to the condylar blade plate can be achieved with the use of the standard blue locking plates placed down the side of the bone with considerably more scope for flexibility. A locking screw that fixes into the end of the plate becomes one construct mechanically which simulates the blade as part of a plate.
Technique
Step 1 – Reduce the fragment.
Tip: In clinical cases an oblique k-wire may be used to hold the fragments.
Step 2 – Select an appropriately sized condylar blade plate and place it along the lateral aspect of the bone with the pin pointing away from the bone. Mark the position of the screw hole that is adjacent to the pin on the bone.
Step 3 – Drill accurately parallel to the articular surface and perpendicular to the edge of the bone. This is the track that the blade is going to take. Use the depth gauge to ascertain the depth, and trim the length of the blade accordingly.
Tip: Cut across the pin to prevent it spatulating and becoming difficult to insert.
Step 4 – Place the condylar blade down the hole and, using the plate benders, accurately contour the plate so that it fits snugly against the side of the bone along its length.
Step 5 – Only when you are happy that the blade plate is accurately contoured, then fix the most proximal screw to the shaft of the bone to provide correct alignment and orientation. Consider whether or not this needs to be a neutral or a compression screw. If it is to be used as a compression screw, consider whether the distal fixation of the distal fragment is adequately stabilised to take the load.
Step 6 – Apply the remaining screws, as needed, with consideration for whether lagging is required.
Note: Other fragment sets may have a blade plate with an oval hole as the first hole above the blade. This allows a screw either to be placed obliquely as a lag screw or transversely and off centre in the hole to allow compression as described in the previous chapter.
Condylar Blade Plate using Locking Plate
Technique
Step 1 – Reduce the fragment.
Step 2 – Select an appropriate plate and place it along the lateral aspect of the bone and ensure adequate number of holes both sides of the fragment. A ’T’ or ‘Y’ plate may be preferable.
Step 3 – Using the plate benders accurately contour the plate to the side of the bone. The plate benders are labelled up and down and should be used in adjacent holes.
Step 4 – Progress as shown. Don’t completely lock screws in place until satisfied with screw and plate position.
Step 5 – Apply the remaining screws, as needed, with consideration for whether lagging is required (use bronze screw). Further distal screw required in this last image.
