Open reduction, internal fixation (ORIF)

Perilunar fracture dislocations present an extensive spectrum of injury. Fractures of carpal bones around the lunate may occur, instead of pure ligamentous ruptures, when the disrupting force propagates around the midcarpal joint: 95% of all perilunar fractures are trans-scaphoid.
Recognition and repair of all bony and soft-tissue components are essential in order to restore carpal stability, and to prevent posttraumatic degenerative joint disease (DJD).

There are many combinations of injury patterns.
Concurrent bony and soft-tissue lesions of the carpus are not mutually exclusive (e.g. concomittant scaphoid fracture and scapholunate rupture).
The radiograph shows a transscaphoid perilunar fracture dislocation, associated with a fracture of the ulnar styloid.

The proximal pole of the scaphoid was displaced deeply into the second extensor compartment.

For this procedure a combined approach to the perilunate is normally used.

Osteochondral fragments are either fixed, or removed, depending on their size.
Small fragments must be removed, as in this case of an osteochondral fragment from the head of the capitate.

The transscaphoid perilunar fracture dislocation is the most common of all perilunar displacements.

Reduction of the the displaced scaphoid is the first step prior to screw fixation, using a double-pitch headless screw. Preserve the vascular supply that enters through the dorsoradial ridge.

The orientation of the shaft of the first metacarpal should act as an alignment guide for K-wire insertion.

The entry point is at the proximal pole, directly adjacent to the scapholunate ligament insertion.
Image intensification is used to confirm accurate wire placement along the scaphoid axis, and as perpendicular as possible to the fracture plane.
Do not penetrate the scaphotrapezial joint with the guide wire.

Two methods can be employed for measuring the required screw length:

1. Insert a measuring device over the guide wire, through the dedicated drill guide which must be firmly positioned on the proximal pole for a reliable measurement.
2. If no drill guide was used, take another guide wire of the same length and place its tip onto the insertion point. The length that protrudes beyond the end of the first guide wire indicates the length of the drill hole for the screw.

In most cases, a 16-20 mm screw is the appropriate size.

Using a power drill will exert less force on the fragments than manual drilling, and reduces the risk of displacement. A small power drill with slow rotation is preferred.
Use Ringer lactate to cool the drill bit, in order to minimize thermal damage.
Then tap the drill hole manually if no self-tapping screws are used.

The proximal end of the screw should be advanced until it is buried under the subchondral bone.

Caution
The distal thread must not lie within the fracture plane as this would prevent compression and risk fracture separation.

From the plain radiographs, it is not always possible to recognize the presence of comminution. Post-reduction CT scans are always advisable.

In cases of extensive comminution, or scaphoid bone defects, fixation with a headless screw alone is unlikely to give enough stability.

In cases of comminution, a combination of two screws, or a screw and a K-wire, may be necessary to achieve the required stability.
Before the final fixation, reduce all displaced fragments.

The goal of final scaphoid fixation is to achieve sufficient stability. Insert the screws and/or K-wires in such a way that this goal is achieved. Use bone graft from the distal radius for scaphoid bone defects, in order to assist fracture healing.

The accompanying illustrations show a comminuted scaphoid fracture fixed with two headless screws. The second screw was needed to improve stability of the construct.

In transscaphoid perilunar injuries, the lunotriquetral ligament can be torn from the lunate (in most cases), from the triquetrum, in its mid-substance, or as a bony avulsion from either bone. There must be sufficient ligament remnant for repair with bone anchors. Otherwise, it is repaired by direct suture.

A suture anchor is inserted into the debrided area of the avulsion.

The LT joint is reduced, and two 1.4 mm K-wires are inserted percutaneously from the ulnar side of the triquetrum across the LT joint into the lunate. Confirm the position of the wires using image intensification.
The suture of the ligament can now be completed.

A palmar approach will reveal the characteristic disruptions of the extrinsic palmar ligaments, which occur through the space of Poirier. A rent in the palmar capsule, between proximal and distal ligament arches, exposes the midcarpal joint.

The midcarpal joint is irrigated. Loose bodies or subchondral flakes are removed, and the rent is repaired anatomically using interrupted resorbable sutures.

In cases of larger osteochondral defects (as in this illustration of a defect of the articular surface of the head of the capitate), aftertreatment with an external fixator is advisable.

Gentle distraction during healing offloads the damaged joint and facilitates the formation of fibrocartilage.

A palmar approach will reveal the characteristic disruptions of the extrinsic palmar ligaments, which occur through the space of Poirier. A rent in the palmar capsule, between proximal and distal ligament arches, exposes the midcarpal joint.

The midcarpal joint is irrigated. Loose bodies, or subchondral flakes, are removed,...

... and the rent is repaired anatomically using interrupted resorbable sutures.

Immobilize the wrist with a well-padded below-elbow splint for 2 weeks.

While the patient is in bed, use pillows to keep the hand elevated above the level of the heart to reduce swelling.

For ambulant patients, put the arm in a sling and elevate to above the heart.

After 14 days remove the sutures, check the skin over the K-wires, and apply a below-elbow scaphoid cast.

Immediately postoperatively begin active, controlled digital range-of-motion exercises.

Load bearing through the splinted wrist must be avoided. The cast is changed and the skin regularly checked every 2 weeks in the outpatient clinic.

Cast immobilization is usually continued until 8 weeks postoperatively. At that time, an x-ray of the wrist is mandatory to assess bony healing and the position of the carpal bones. If bony healing can not be assessed from the plain radiographs, a CT scan is recommended.

The K-wires that are securing additional ligament lesions are removed at 8 weeks with appropriate pain control.

When bony union is confirmed, the patient can start with range-of-motion exercises of the wrist. A removable wrist splint may be used for patient comfort for a few more weeks.

The importance of mobilization must be emphasized to the patient and rehabilitation should be supervised by a physical therapist.