1 Introduction topenlarge
Trochlea fractures are difficult to see on radiographs. Computed tomography - with 3D reconstruction in particular - is especially useful for understanding the fracture anatomy.
There is often complex articular comminution.
2 Open reduction topenlarge
Clean the fracture site
An olecranon osteotomy is used for exposure.
Clean out the fracture by removing blood clots, unfixable loose pieces of bone, and any interposed tissue. Inspect the joint to ensure that no additional intraarticular fracture component is missed.
Disimpact fracture fragments
Many of the displaced fracture fragments are stable, which may suggest that they are appropriately aligned; however, these are often impacted into incorrect alignment. Using controlled force, these fragments must be disimpacted gently and brought into alignment with intact parts of the bone.
Reduce the fracture.
Monitor fracture reduction by realigning the articular fracture lines.
Provisionally fix the fragments with small, smooth K-wires.
3 Internal fixation topenlarge
Headless screws, cannulated or non-cannulated, can be used to secure articular fragments that are large enough and have adequate bone quality.
Small threaded K-wires or absorbable pins
Smaller articular fragments are secured with small threaded K-wires or absorbable pins.
4 Osteosynthesis of the olecranon osteotomy topenlarge
Drill hole for wire
Using a 2.5 mm drill, make a coronal hole in the proximal ulna from ulnar to radial side, to pass the figure-of-eight wire.
Prepare a 0.8 mm wire by making a loop approximately one third along its length. Insert the shorter segment of the wire through this drill hole.
Reduction of the olecranon
Reduce the olecranon osteotomy with pointed reduction forceps.
Use the figure-of-eight tension band wiring technique to obtain stable fixation. Two K-wires are drilled parallel across the osteotomy.
The K-wires can be directed down the shaft of the ulna, or alternatively aimed anterior so that they engage the anterior ulnar cortex, just distal to the coronoid process: this may help to limit the potential for wire migration.
Obtain correct K-wire tension
The wire loop has to go underneath the triceps tendon.
Double twist the wire loop to obtain equal tension on both sides. The cut wire loops are then impacted firmly onto the bony cortex of the ulna.
Cut the wires to the appropriate length and bend them. Impact the bend K-wire tip into the olecranon, being sure to bury them beneath the triceps tendon.
Completed osteosynthesis of olecranon
The illustration shows the completed osteosynthesis of the olecranon.