1 Choice of surgical procedure top
The soft-tissue conditions usually dictate the choice of procedure: early single-stage, or multiple-stage surgery. The decision is based rather on the individual situation than on general principles.
Displaced fractures with minimal closed soft-tissue injury
(Tscherne classification, closed fracture grade 0, rarely grade 1)
Reconstruction may be achieved by a single-stage open procedure, embracing the classical four steps of Rüedi and Allgöwer: Reconstruction of a fractured fibula followed by reconstruction of the tibial joint surface, use of autogenous cancellous or corticocancellous bone graft (if necessary) and support by a buttress plate.
Grossly displaced fractures and / or fractures with moderate to severe closed soft-tissue injury
(Tscherne classification, closed fracture grade 2 or 3)
It is generally advisable to proceed in two or more stages:
First stage: Closed reduction, fibular reduction and stabilization, and joint bridging external fixation. Accurate reduction and stabilization of the fibula re-establishes its proper length, alignment and rotation. If fibular comminution prevents an accurate reduction, it may be better not to fix the fibula in the first stage. Joint spanning external fixation should be remote from the fracture. External fixation pins should avoid the planned future surgical approaches including the neck of the talus.
Second stage: Definitive open reconstruction after 5-21 days. Definitive operative treatment of the articular surface should be delayed until the soft tissues have recovered sufficiently to allow definitive reconstruction. Return of skin wrinkles is a good sign of soft-tissue recovery.
Open pilon fractures
These are very severe injuries often requiring plastic surgery for soft-tissue reconstruction. The management includes the following stages:
1. Wound debridement and lavage. Fibular stabilization and fixation (if needed and the soft tissues allow). Joint-bridging external fixation.
2. At 48 hours: Second look with repeated lavage (redislocation of fracture/joint!) and redebridement if necessary. Soft-tissue coverage (local or free flap). Reconstruction of the tibial articular surface may be possible at the same time and should be considered if the exposure for flap coverage allows.
3. Third stage: Definitive stabilization between the articular segment (joint block) and tibial shaft by internal fixation (or external fixator) is typically delayed until soft-tissue recovery has occurred. However, this may be performed at the time of flap coverage in certain circumstances.
2 Sequence of bone stabilization - fibula or tibia first? topenlarge
Sequence of bone stabilization - fibula or tibia first?
In type 43-C3 fractures, the fibula may be fractured as well and needs to be stabilized.
Simple fracture of the fibula
If the fibular fracture is simple, this fracture is addressed as first step by open reduction and stable plate fixation. This indirectly reduces the antero- and posterolateral fragments of the articular surface of the tibia by the usually intact syndesmotic ligaments. Reconstruction of the articular surface of the tibia and stable plate fixation then follow the fixation of the fibula.
Complex fibular fracture
A complex fibular fracture (a) is preferably addressed after reconstruction of the tibia. The syndesmotic ligaments are usually intact, so gross realignment of the fibula occurs with reduction and fixation of the tibia (especially of the anterolateral and posterolateral fragments) as shown in figure (b).
However, it is essential to achieve correct length, rotation, and axial alignment of the fibula. This may be achieved with a MIPO technique (c) using a long bridging plate (d).
3 Planning of reduction and fixation top
Planning of reduction techniques
Preoperative planning is an essential part of treatment of all pilon fractures. It consists of:
- obtaining good AP and lateral x-rays of both injured and uninjured side; CT if needed
- careful study of the x-rays and CT scan
- tracing AP and lateral x-rays of normal side
- identifying the individual fracture fragments
- drawing the fracture fragments, reduced, onto the normal tracing
- considering reduction techniques
- choosing and drawing in fixation implants
- choice of surgical approach
- preparing a list of operative steps
Planning of reduction techniques
For the reduction of all type B and C pilon fractures with displaced central fragments and/or impaction the exact approach is planned from the CT scan (see enlarged image). The approach is selected based on fracture location and type. Usually, it is either anteromedial or anterolateral, but occasionally posteromedial or posterolateral approaches are necessary.
These fractures cannot be reduced by ligamentotaxis alone and always need some direct manipulation and inspection of the joint. Therefore, a limited open approach is required at least for the reduction of the articular surface.
The illustrated case is a type 3A open fracture. The wound is posterior, with partial rupture of the Achilles tendon. One large posterior metaphyseal fragment had to be removed at the first operation (debridement, wash-out and joint bridging external fixation). 48 hours after injury, the traumatic wound was re-debrided and closed. A subsequent CT scan clarifies the comminution of the articular block.
4 Application of a distractor topenlarge
A distractor (or external fixator) is a very helpful tool for reduction. Distraction is used for the open reduction and plate fixation of the fibula as first step (if not yet already fixed) and for the reduction of the articular surface of the tibia as a second step.
Schanz screws are positioned in safe zones of the tibial shaft and talar neck (or the calcaneal tuberosity). In case of previously applied joint-bridging fixator, the already existing Schanz screws can be used. Pull the talus (or calcaneus) in a caudal direction under distraction to allow a good view into the ankle joint. A new distal pin in the talus may provide the best fracture control and visualization.
5 Plating of the fibula topenlarge
Through a posterolateral straight approach, the fibula is stabilized with a plate. In the illustrated case a LCP 3.5, with locking head screws, is used as a bridge plate because of the somewhat comminuted fracture. It is essential to achieve correct alignment for length, axis and rotation.
6 Reduction of articular segments top
Exposure and cleaning of the fracture area
An anteromedial approach to the distal tibia is performed. Avoid extending this more proximally than necessary for articular exposure. Open the fracture zone by separating the anterior fragments through the sagittal fracture line. The fracture and joint is irrigated and cleansed of clotted blood and small osteochondral fragments.
In the illustrated case with type III A open soft-tissue injury (posterior), all avascular metaphyseal fragments must be removed, leaving a large proximal metaphyseal defect. Inspect and document any cartilage damage on the talar dome. Now the central part of the fracture with several articular fragments is visible.
Reduction of the central fragment
First, realign the central fragment with the posterolateral part of the articular block.
This preliminary reduction is stabilized with a small K-wire inserted from anteriorly. This wire will become part of the fragment’s definitive fixation when it is cut and buried inside the completely reduced fracture (“lost” K-wire).
Cutting the buried K-wire requires sufficient access. This may be easier before the other fracture fragments are reduced.
Reduction of the anterolateral fragment
Reduce the anterolateral fragment now under visual control anatomically to the posterocentral block. Reduction is retained by a small K-wire, inserted percutaneously through a separate small anterolateral incision.
Reduction of the medial fragment
Finally, reduce the medial fragment, with attached malleolus, to the lateral articular block. Stabilize it with a Weber clamp, which is then replaced with two K-wires.
Burying the K-wire
First, cut the K-wire in the central piece as close to the bone as possible. Then, impact the wire to bone level, as shown in the illustration. This will allow the anterior metaphyseal fragment to be reduced anatomically into the remaining defect.
Alternatively, this K-wire could have been replaced by a resorbable pin.
Reduction of the metaphyseal fragment
Next, close the anterior cortical defect just above the subchondral bone.
The illustration shows the defect filled with the large anterior metaphyseal fragment which has remained attached to the lateral periosteum. This fragment is fixed preliminarily with a K-wire.
Correct reduction is confirmed and documented by fluoroscopy. (See also assessment of reduction.)
7 Screw fixation of the articular block topenlarge
Stabilize the reduced articular block with several 3.5 mm lag screws, one inserted from anterolateral to posteromedial, another one inserted from anteromedial to posterolateral.
The large, anterior metaphyseal fragment is also fixed with two 3.5 mm lag screws, one directed to the posterolateral, the other one to the posteromedial metaphysis. If the screws provide adequate stability, the anterior K-wires can now be removed.
8 Implant choice top
Plates are under constant development. A variety of anatomical plates are available from different manufacturers.
In case of a large meta-diaphyseal defect, a stronger plate should be used. The LCP distal medial tibia plate is thicker than the distal part of the LCP distal tibial metaphyseal plate. Therefore it was used for the illustrated case.
The selected plate is anatomically preformed and usually has not to be contoured. Alternatively, a cloverleaf plate or two small (eg, one-third tubular) plates could be used.
9 Plate fixation topenlarge
The plate is inserted epiperiosteally on the anteromedial aspect of the distal tibia, after developing a subcutaneous tunnel.
First shorten the K-wires (to 5-10 mm above the bone surface) so that the K-wires can pass through screw holes. If this is not possible, change the position of the K-wires to allow placement of the plate.
Definitive stabilization of the articular block
Position the plate at the correct level to allow the application of two lag screws from medial to lateral through the plate, close to the articular surface. Inserted one at a time, they replace the K-wires. The screws pass below the previously placed AP screws. One is directed into the anterolateral, and the other one into the posterolateral fragment.
With this step, the articular block is definitively stabilized.
Secure fixation of the plate to the articular block is important for bridging the large metaphyseal defect. Locking head screws may be optimal for this purpose. This justifies selection of a locking plate, if it is available.
Proximal plate fixation
In the illustrated case, proximal fixation of the plate to the diaphysis is achieved with locking head screws inserted close to the defect and at the proximal end of the plate. Additional plate length improves proximal fixation. With good bone quality, non-locking cortical screws can be used.
It is essential to obtain correct length, axis and rotation before the first screw is applied in the diaphysis. Careful use of fluoroscopy and physical exam are essential for assessing alignment.
The whole fracture zone is now stabilized. When the soft tissues are healed (4-6 weeks), the large lateral bone defect will be filled with an extensive cancellous bone graft from the posterior iliac crest.
10 Assessment topenlarge
The x-ray control at the end of the operation confirms the anatomical reduction of the joint block and correct alignment of the distal fibula and tibia. Note the “lost K-wire” which is slightly overlapping the posterior bone border. Before wound closure, radiographic confirmation of joint congruity, length, and axial alignment is mandatory (see also assessment of reduction).
In the illustrated case, the dead space (bone defect) was not initially filled. Alternatively, antibiotic bone cement, as a block or beads, can be used to fill the defect temporarily.
11 Bone grafting topenlarge
After six weeks, the soft tissues have healed uneventfully, allowing the planned bone grafting of this large defect. The consolidation of the fibula and articular block has already started with a still stable fixation.
12 X-ray follow-up topenlarge
X-ray follow-up at 3 months after bone grafting
The entire bone graft has healed in nicely. The fibula and also the distal tibia seem to be united. Therefore, full weight bearing was started at that time.
13 Pearl - Fixation with traditional plates topenlarge
If locking plates are not available, traditional plates can be used for ORIF of C-type fractures of the distal tibia. The standard traditional plate is the cloverleaf plate 3.5, which can be placed medially, anteromedially or anteriorly, depending on the fracture pattern.
The enlarged illustration, showing injury, preoperative plan, and end result demonstrates an alternative fixation technique. Double plating, with two one-third tubular plates (or others), can be used instead of locking plates. However, the latter may offer greater stability, particularly in osteoporotic bone.