The chosen 4.0 mm cancellous screw must lie with its threads completely beyond the fracture line and totally within the Volkmann's fragment, to achieve good interfragmentary compression. If possible, engage the posterior cortex. Use a washer.
If the thread of the 4.0 mm cancellous screw should come to lie on both sides of the fracture, insert a 3.5 mm cortex screw as a lag screw instead, overdrilling the anterior tibia as a gliding hole.
Insert the first screw
Remove one K-wire and drill a hole through both fragments parallel to the K-wire, using a 2.5 mm drill bit and protection sleeve.
Measure the depth of the hole and tap the near tibial cortex with the 4.0 mm cancellous tap and protection sleeve. Insert a 4.0 mm cancellous screw with a washer.
Insert the second screw
Remove the K-wire.
As a rule, a screw which is 5 mm longer than the measured size must be chosen for the second screw as the more medial portion of even a large Volkmann's fragment is often not deep enough to accommodate the whole of the threaded portion of the cancellous screw.
The screw tip may therefore protrude a little posteriorly.
If the thread of the 4.0 mm partially threaded screw would still come to lie on both sides of the fracture, or to prevent protrusion of the tip of the screw into the posterior soft tissues, insert a 3.5 mm cortex screw as a lag screw.