1 Principles topenlarge
When ever possible because of the size of the fracture fragment, two-point fixation is recommended, to ensure interfragmentary fixation and rotational stability.
In lateral recumbency, the fragment should always be positioned uppermost.
2 Reduction topenlarge
Minimally displaced fractures may require no reduction prior to internal fixation.
Displaced fractures must be reduced appropriately.
Either small incisions or arthroscopic control are useful in assisting anatomic reduction.
Flexion and manipulation of the fetlock joint is often needed to obtain reduction.
Insertion of the screws is accomplished by means of stab incisions through the associated collateral ligament.
Prior to placement of the screws, temporary fixation using a 2 mm drill bit, a reduction forceps and/or radiodense markers is applied to radiographically identify the ideal position for the screw(s).
3 Fixation topenlarge
Insertion of the first screw
The ideal position of the first screw is perpendicular to the fracture plane and as close as possible to the joint surface.
A second, usually more distal screw should be used if the fragment is large enough to accommodate two screws.
Number and size of screws
Interfragmentary fixation is usually first achieved with a 4.5 mm cortex screw inserted in lag fashion.
Subsequently either a 4.5 mm or 3.5 mm screw are inserted, depending on the fracture fragment size. In some instances, two 3.5 mm screws will be more appropriate than a single 4.5 mm screw.