1 Principles topenlarge
Indication for ORIF is deformity, such as malrotation or malangulation.
Open reduction internal fixation with one or more lag screws may be performed.
When only one lag screw is used, the fixation should be protected with a plate. This enhances the degree of fixation and permits a greater degree of weight bearing which facilitates functional rehabilitation. If possible, insert the lag screw through the plate, as this increases the degree of stability.
Percutaneous K-wire fixation
Alternatively, closed reduction using fixation with two or more K-wires may be performed. This may be indicated in patients with poor soft tissue envelope or extensive medical comorbidities.
A minimum of two K-wires are required for rotational stability. K-wires may be placed parallel or crossed. For parallel placement, K-wires enter the distal phalanx and exit the first metatarsal proximal to the head.
If crossed K-wires are to be inserted, the fracture site should be proximal or distal to where the wires cross.
2 Reduction and preliminary fixation topenlarge
Diaphyseal fractures of the proximal phalanx of the hallux are best approached through a medial approach. (see Medial approach to the hallux).
Use a periosteal elevator as a lever to reduce the fracture.
Restore anatomical axial rotation, length and angulation.
Placement of the clamp
Apply the points of the reduction clamp so that the points are at right angles to the fracture line. This helps in reducing the fracture and in applying compression.
Once reduced and compressed, maintain the reduction with a K-wire.
The K-wire can be introduced through the same approach, but it must be positioned in such a way that it will not interfere with subsequent fixation.
3 Fixation topenlarge
Lag screw insertion
These fractures usually have inherent stability, which makes lag screw fixation sufficient. Rarely a plate must be used to protect the lag screw fixation.
Preparation and shaping of the plate
Cut the plate to the appropriate length.
Bend and twist the plate to contour it to fit the anatomy of the bone.
Application of the plate
Occasionally the middle screw has to be left out if it interferes with the lag screw.