1 Preliminary remarks topenlarge
Fracture assessment and decision making
A3 type fractures are extraarticular but multifragmentary. They may often be associated with an ulnar styloid fracture.
In A3.3 fractures, because of extensive comminution, fixation should aim to restore length, axis and rotation. The function of the plate is bridging the comminution and promoting secondary healing with callus formation.
As these injuries are often associated with disruption of the DRUJ, before starting the operation, the uninjured side should be tested as a reference for the injured side.
Bridge plating of the distal radius - plate choice
In the presence of extensive metaphyseal comminution, conventional plates do not allow for enough purchase particularly in the proximal fragment. Specially designed, longer, angular stable plates have been developed in order to allow stable fixation of the distal fragment and metaphyseal bridging of the comminution.
2 Radial plate fixation topenlarge
Radial plate fixation
The radial shaft is approached using a classical Henry’s palmar (anterior) approach.
The plate is pre-contoured distally, so it is already adapted to the palmar curvature of the distal radius.
The plate is first positioned distally on the flat intact palmar surface of the distal radius and fixed with distal locking screws parallel to the articular surface. The distal end of the plate should end at the anatomic watershed zone of the distal radius.
The first screw inserted is in the hole on the ulnar side of the plate and its position should be checked under image intensification with the hand elevated 20-30° off the table – in lunate facet view.
The other distal screws should be inserted in a way that the radial inclination of approximately 20° is restored.
Restoring radial length
The correct length of the radius in relation to the ulna should be established preoperatively by taking radiograph of the opposite wrist. The length of the radius in relation to the ulna is then achieved by by inserting a unicortical screw just proximal to the proximal end of the plate, and then using a spreader, as illustrated, to move the plate gently distally.
Once the correct length is achieved, the plate is provisionally fixed proximally with standard screws.
The relationship of the radius to the distal ulna is checked under image intensification before the plate is fixed with additional proximal screws
3 Assessment of Distal Radioulnar Joint (DRUJ) top
Before starting the operation the uninjured side should be tested as a reference for the injured side.
After fixation, the distal radioulnar joint should be assessed for forearm rotation, as well as for stability. The forearm should be rotated completely to make certain there is no anatomical block.
The elbow is flexed 90° on the arm table and displacement in dorsal palmar direction is tested in a neutral rotation of the forearm with the wrist in neutral position.
This is repeated with the wrist in radial deviation, which stabilizes the DRUJ, if the ulnar collateral complex (TFCC) is not disrupted.
This is repeated with the wrist in full supination and full pronation.
In order to test the stability of the distal radioulnar joint, the ulna is compressed against the radius...
...while the forearm is passively put through full supination...
If there is a palpable “clunk”, then instability of the distal radioulnar joint should be considered. This would be an indication for internal fixation of an ulnar styloid fracture at its base. If the fracture is at the tip of the ulnar styloid consider TFCC stabilization.