1 Indications topenlarge
Fractures of the metaphysis can be transverse, oblique, or comminuted.
Reduction is achieved by traction and digital manipulation. When the fracture
is stable, it can be treated nonoperatively.
If the fracture is irreducible, ORIF is indicated.
Other indications for ORIF are open fractures or soft-tissue lacerations.
2 Reduction topenlarge
Indirect reduction by traction
Reduction can be obtained by traction and flexion exerted by the
Confirm reduction using image intensification.
Often, these fractures are stable after reduction, in which case nonoperative treatment is indicated.
Direct reduction is necessary when the fracture can not be reduced by
traction and flexion, or is unstable because of surrounding soft-tissue
When indirect reduction is not possible, this is usually due to interposition of parts of the extensor apparatus.
Use two pointed reduction forceps for direct reduction.
Insert a K-wire for provisional fixation.
At this stage, after provisional fixation, it is advisable to check the alignment and rotational correction by moving the finger through a range of motion.
Rotational alignment can only be judged with the fingers in a degree of flexion, and never in full extension. Malrotation may manifest itself by overlap of the flexed finger over its neighbor. Subtle rotational malalignments can often be judged by tilting of the leading edge of the fingernail, when the fingers are viewed end-on.
If the patient is conscious and the regional anesthesia still allows active movement, the patient can be asked to extend and flex the finger.
Any malrotation is corrected by direct manipulation and later fixed.
Using the tenodesis effect when under anesthesia
Under general anesthesia, the tenodesis effect is used, the surgeon fully flexing the wrist to produce extension of the fingers, and fully extending the wrist to cause flexion of the fingers.
Alternatively, the surgeon can exert pressure against the muscle bellies of the proximal forearm to cause passive flexion of the fingers.
3 Plate preparation topenlarge
Two types of plate are available for treatment of this fracture:
- 1.5 Minicondylar plate
- 1.3 or 1.5 T-plate (adaption plate)
Select a plate according to fragment size, fracture geometry, and surgeon‘s preference.
Measure for length of the blade
Measure the length of the drill hole using a measuring device.
Cut the blade to the determined length, so that it just fills the drill hole.
Avoid protrusion from the opposite cortex, as friction during movement and eventual ligament injury may result.
Trim the plate
Adapt the plate length to fit the length of the proximal phalanx. Avoid
sharp edges which may be injurious to the tendons. There should be at least 3
plate holes distal to the fracture available for fixation in the diaphysis. At
least two screws need to be inserted into the diaphysis.
Pearl: Cut the blade transversely
If you cut the blade on the flat, it will compress and widen very slightly as it is cut. This makes its maximal width very slightly larger than 1.5 mm. It may not fit in the 1.5 mm hole that you have drilled.
Therefore, cut the blade on edge (to deform it through its narrower dimension) to the correct length. The resultant tip is somewhat arrow-shaped.
Contouring of the plate
Use pliers to contour the plate so that it fits exactly the anatomy of the
base of the proximal phalanx.
The plate was designed for condylar fractures and is precontoured to fit around a condyle. It has to be adapted for the less curved shape of the base of the proximal phalanx.
4 Fixation topenlarge
Determine location of drill hole
In order to determine the position of the first drill hole, it can be very helpful to turn the plate over and use it as a template ...
... as shown in this photo.
Drill a 1.5 mm transverse hole through the base of the proximal phalanx adjacent to the subchondral bone.
The drill hole needs to be dorsal enough as to leave enough space for the plate’s most proximal screw hole.
Introduce the blade into the drill hole. Gently push with the thumb until the plate is fully seated.
Align the plate with the diaphysis
Before inserting the first (distal) screw, ensure that the plate is in line with the phalangeal diaphysis in the sagittal plane by rotating it around the long axis of the blade.
Drill eccentric distal hole
Use a 1.1 mm drill bit to prepare the first screw hole at the distal end of the plate.
This hole must be drilled eccentrically in order to produce axial compression.
Measure the screw length and insert a self-tapping 1.5 mm screw as a load screw.
Tightening this screw will compress the fracture axially.
Insert proximal screw
The proximal screw is inserted next in a neutral position.
The screw should engage the far cortex.
Be careful to avoid screw protrusion through the far cortex, as ligament injury may result from friction during movement.
Insert a third screw into one of the diaphyseal holes in a neutral position in order to complete the fixation.