1 Principles topenlarge
Triangle of stability-concept
The mechanical properties of the distal humerus are based on a triangle of stability, comprising the medial and lateral columns, and the articular surface.
In complete articular fractures, all 3 columns have to be restored.
2 Opening the joint topenlarge
Cleaning of the fracture site
Clean out the fracture by removing blood clots, loose pieces of bone, and any interposed tissue.
3 Reconstruction of the articular surface topenlarge
Reduce the articular fragments. In good quality bone, use pointed reduction forceps.
In poor quality bone, use temporary fixation with a K-wire.
Use a lag screw (a partially threaded screw, or a fully threaded screw with
overdrilling the near fragment) to obtain
In osteoporotic bone, use a position screw.
Try to use two screws to avoid rotational instability.
In very distal fractures, generally only one screw can be inserted.
An additional K-wire can be used to obtain rotational stability.
4 Condylar reattachment topenlarge
Reduce the reconstituted articular (condylar) block to the metaphysis and use K-wires for preliminary fixation.
The plates must be carefully contoured using an appropriate malleable template.
Place the lateral column plate dorsally and the medial column plate medially. In this position they form an angle of approximately 90 degrees to each other.
First place a 3.5 mm reconstruction plate posterolaterally. It may curve around the capitellum which is non-articular posteriorly.
In distal fractures, the reconstruction plate can be bent all the way to the edge of the articular surface. It will not interfere with the radial head during extension of the joint. The more bone is covered by the plate, the more the stability that can be achieved.
Placement of the lateral plate
Place a K-wire through the distal hole. Now insert the proximal screw as a load screw. As the plate is pulled proximally, stable contact with the bone is obtained.
Fix the plate to the bone by inserting the remaining screws.
Place another plate medially on the crest of the medial supracondylar ridge, at a right angle to the plane of the lateral plate to increase stability.
It is recommended to insert the distal screw into the trochlea below the medial epicondyle.