Position of the distal screw
The position of the distal screw depends on the geometry of the fracture
line which separates the condyles, and the size of the smaller fragment. This
screw has to be planned carefully.
Vertical fracture plane
If the intercondylar fracture line is vertical, the lag screw will have to
be inserted transversely, distal to the attachment of the collateral ligament,
in order to cross the intercondylar fracture plane as perpendicularly as
possible, and to secure the small fragment.
Oblique fracture plane
If the intercondylar fracture line is oblique, and the smaller fragment is
large enough, the distal lag screw will be inserted obliquely, perpendicular to
the intercondylar fracture plane, its point of entry being proximal to the
attachment of the collateral ligament, and extraarticular.