Pilon Fractures Treatment & Management

Pain relief is necessary. Antibiotic prophylaxis is used for open fractures and for internal fixation. Conservative treatment may be indicated in undisplaced fractures, which can be managed with cast immobilization.

Prehospital care

Prehospital care depends on other associated injuries, but if an isolated lower limb fracture is suspected, the following steps are important:

• Check for any neurovascular compromise.
• Correct any grossly deformed limb.
• Elevate and support the limb in a temporary splint.
• Cover open fractures with sterile dressings.
• Apply local pressure to control any active bleeding.
• Administer pain-relieving medication.

Emergency department care

• Prehospital care is administered if not previously instituted.
• Antibiotic prophylaxis includes cephalexin for mildly to moderately contaminated wounds, with the addition of an aminoglycoside for highly contaminated wounds. Administer vancomycin and gentamicin if the patient is allergic to penicillin.
• Leave fracture blisters intact. Once ruptured, blisters are more likely to become contaminated by skin flora.
• For open fractures, obtain a digital photograph for the record before sterile dressings are applied to help minimize the number of times the dressings are taken down before definitive debridement.
• Tetanus immunization status should be checked. If the patient has not been immunized or if there is gross contamination, tetanus immunoglobulin should be administered.
• Radiographs are obtained and consultations requested.

Consultations

• Consult an orthopedist.
• Consult a plastic surgeon when soft tissues are lost, compromising cover over exposed bone and/or tendons.
• Consult a vascular surgeon. Blood flow to the foot may be compromised in the case of severe deformity. If it is not restored and/or if an open wound with vascular injury is present, angiography may be necessary along with involvement of the vascular surgeon.

Timing of surgery

• Poor timing is associated with poor outcomes. Soft tissues must be ready for the second insult dealt by surgery.^[8]
• The nature and timing of surgery is based on the following:

  • Duration elapsed from the time of injury
  • Condition of the soft tissues
  • Presence of any other additional injuries
  • Presence of open wound and/or vascular compromise
• Open fractures require urgent and thorough debridement. In the case of vascular injury or compromise, vascular surgery is needed to restore blood flow. If adequate soft-tissue cover cannot be achieved, plastic surgery is required.

Stabilization of fracture

Definitive surgery to restore the fragments and stabilize the fracture is delayed to allow soft tissues to recover from the traumatic injury. Adding surgical insult to already injured or compromised soft tissues leads to a higher incidence of wound complications and poor outcomes; therefore, surgical intervention is staged.^{[9, 10, 11, 12]}

• Preliminary stabilization is usually achieved with an external fixator, with or without fixation of the fibular fracture.^[13] This is performed in the presence of soft-tissue swelling (see image below). External fixator stabilizing the pilon fracture. Swelling has resolved, and blisters have healed.

  • It helps with pain relief and in the resolution of soft-tissue swelling.
  • It helps dressing changes and wound healing in open fractures.
  • It prevents length-countering contractures in soft tissue, which can make subsequent surgery difficult.
  • The aim is to maintain alignment, not necessarily at this stage itself, to accurately reduce the articular surface.
  • When pin-site placement is considered, further surgery, such as rotational flaps or incisions for open reduction and internal fixation, must be considered.
  • Excessive distraction at the ankle joint is avoided because it can cause traction neuropathy and compartment syndrome.
• Definitive surgery is undertaken when the condition of soft tissues is optimized. This is usually when the blisters have epithelized or healed and the skin is wrinkled. Many options for definitive surgery are available; these include the following^{[14, 15]} :

  • Open reduction and internal fixation
  • External fixation (either spanning the ankle or not)
  • Limited internal fixation with external fixation
  • Percutaneous plating

Consent is essential and includes a fully informed discussion to explain the nature of the injury; the options, risks, and benefits; the need for bone grafting; the likely rehabilitation plan; the potential for amputation, either acutely or in the future; and the prognosis.

Careful and detailed planning of the procedure, based on findings from radiography and CT scanning, is necessary to anticipate any difficulties and save time. Determine (1) the sequence and strategy to reduce and stabilize the fragments, and (2) the choice of implants and alternatives.

The surgery is performed on a radiolucent table with a fluoroscope and portable radiograph machine available. Antibiotic prophylaxis is administered at the time of anesthesia induction.

Positioning

The surgery is performed with the patient placed supine with a bump under the ipsilateral hip; this allows access to both sides of the ankle. The opposite leg heel is elevated to relieve pressure on the calf and prevent deep vein thrombosis. All bony prominences are padded.

A thigh tourniquet placed after elevation helps achieve exsanguination for a bloodless field. In addition to the extremity, the iliac crest area should be prepared and draped in a sterile fashion in case a bone graft is required.

Approach

The surgical approach depends on the fracture pattern, the method of stabilization, and the implant choice. Essentially, the aim is to restore the tibial articular surface and stabilize the articular block to the metaphysis in an anatomic alignment. Restoration of fibular length may aid in this process.^[16]

Percutaneous or minimally invasive fixation

The articular fragments can be reduced by closed techniques or through minimally invasive methods using Kirschner wires (K-wires) to "joystick" them into position. Once they are aligned, cannulated screws can be inserted under fluoroscopic guidance. This percutaneous technique, as described by Syed and Panchbhavi, can be used in minimally displaced fractures.^[17] An arthroscope may also be used to visualize that reduction is satisfactory.

If a satisfactory reduction of the articular surface is obtained, the articular block can be stabilized to the metaphysis and held in acceptable anatomic alignment using external fixation. However, this method of percutaneous reduction and stabilization is not suitable for fractures with significant comminution or die-punched articular fragments; this would require open reduction (see images below).

A cadaver study by Graves et al evaluated the validity of using lateral intraoperative fluoroscopic imaging to assess reduction of the tibial plafond articular surface after malreductions were created by displacing a 5-mm osteochondral segment in 6 specimens. This study showed that even on a perfectly lateral fluoroscopic image, it was difficult to discern rotational or translational displacement of a 5-mm osteochondral fragment on a perfect lateral fluoroscopic view of the ankle. Therefore, even with what appears to be a perfect lateral fluoroscopic view intraoperatively, displacement may still be present. When small osteochondral fragments are present, direct visualization of the articular surface is necessary to confidently establish that an anatomic reduction has been achieved.^[18]

Open approach

The location and number of incisions for an open approach is best decided based on the fracture pattern. However, most often, an anteromedial incision overlying the distal tibia just lateral to the tibial crest and following the tibialis anterior tendon provides adequate exposure for open reduction of the tibial articular fragments. Do not create skin flaps, but dissect down to the bone, staying medial to the tibialis anterior and in the fracture plane.

This incision is similar to the incision used in total ankle replacement, and, if reasonable restoration of the ankle is achieved and the ankle becomes arthritic at some point in the future, ankle replacement remains an option. Similarly, just as in total ankle replacement, avoid any tension on the skin. Place 1-2 deep retractors to open up the deep soft tissue for visualization, but, very importantly, ensure the retractors do not rest against or apply tension to the skin.

A pilon fracture with a large posterior fragment deserves special attention. Accurate reduction of the posterior fragment, especially the proximally displacement and rotation, can be difficult through anteriorly placed approaches. In such situations, a posteromedial approach between the posterior tibialis and flexor digitorum longus tendons or a posterolateral approach in between the peroneal and the Achilles tendon provides direct visualization not only for anatomic reduction but also posterior plate application, which serves as a buttress.

Reduction of fracture fragments

The anterior lateral and medial fracture fragments are held apart to visualize the impacted central fragments and the posterior fragment. Sometimes, the posterior fragment must be derotated in the sagittal plane and held temporarily with K-wires. If any central fragments are impacted, they need to be disimpacted, and the resulting cavity in the metaphysis is grafted with bone using an autogenous graft. This can be augmented with synthetic substances such as calcium sulfate, which will set fast and provide some immediate stability for the screw fixation. Then, the anterolateral fragment and medial fragment are restored and held temporarily with K-wires.

Internal fixation

Cannulated screws over washers can be inserted in the appropriate direction in a lag-screw fashion using fluoroscopic guidance in different planes to assess proper placement across fracture planes and into intact bone. Once adequate reduction of the articular block is achieved, it is stabilized to the metaphysis.

Stability of both the medial and lateral columns is important to prevent a varus or valgus deformity. Also important is stability in the sagittal plane. Often, comminution is present in the anterior cortex of the distal tibial metaphysis and at the junction of the metaphysis and diaphysis. Collapse of the anterior column can result in recurvatum deformity.

Internal fixation, external fixation, or both can be used to provide stability to the medial, lateral, anterior, and posterior columns of the tibia.^{[19, 20]} The choice of fixation depends on the condition of the soft tissues and the experience of the surgeon.^[21]

For internal fixation, a low-profile contoured plate can be introduced over the medial aspect of the tibia through the existing exposure and advanced percutaneously proximally into the metaphysis, thus limiting the soft-tissue stripping over the bone and limiting soft-tissue injury (see images below). A smaller anterolateral tibial plate may also be necessary to reduce and hold the anterolateral column out to length.

Distal tibia extra-articular fractures stabilized with anterolateral or medial locking plate constructs demonstrated no statistically significant difference in biomechanical stiffness in compression and torsion testing in a saw-bone pilon fracture model in a study by Yenna et al.^[22]

Locking contoured plates have threads within the screw holes that engage heads of screws to create a fixed-angle construct that improves fixation in osteopenic bone and multifragment fractures. They also have a broader distal end, providing more than a single hole along the width of the plate and thus providing additional purchase in the shorter distal cancellous metaphyseal fragment.

External fixation

An external fixator can also be used to stabilize and align the reconstructed articular block to the metaphysis. The fixator may span the ankle joint and incorporate the foot to give additional stability to the reconstruction, but this limits ankle movement.

A nonspanning fixator allows for early range of motion and cartilage nutrition, and it limits arthrofibrosis. A variety of external fixator frames are available, but a hybrid fixator is commonly used.^{[23, 24]}

The wires used should be inserted carefully so as not to damage any tendons or neurovascular structures.^[25] Usually, one wire is passed through the articular block from posterolateral to anteromedial, starting just anterior to the fibula or through the fibula if the fibula is not plated. To avoid injury to peroneal tendons and the sural nerve, it should not be started posterior to the fibula. A second wire is passed in a posteromedial-to-anterolateral direction, starting in the posteromedial aspect of the tibia anterior to the neurovascular bundle. The wires are placed parallel to and approximately 20 mm proximal to the ankle joint. Olive wires can be used to aid compression across fracture planes or to hold alignment. A ring is attached to the proximal aspect of these wires.

Two 5-mm half pins are inserted in the tibia proximal to the fracture in a sagittal plane. Carbon fiber rods link the half pins to the ring, and the attachments are tightened after reduction of any malalignment, which is checked using fluoroscopy and confirmed with plain radiography.

Fibular plating

Fibular fracture fixation is also important. It may be used to restore the length of the lateral column of the tibia indirectly via ligament taxis on the Chaput fragment anterolaterally and the Wagstaffe fragment posteriorly. It also provides additional strength to the entire reconstruction, especially if some screws are directed into the tibia and through the fibular plate. It helps to prevent valgus deformity.^[26]

The incision to fix the fibula should be positioned slightly posterior to the lateral aspect in order to maximize the width of the skin bridge between this incision and the one on the tibia.

Problems can arise with the fibular plating. A straight or noncontoured plate can push the tibial articular fragment medially and can resist reduction.

Anatomic restoration of length, contour, and axial rotation of the fibula can be challenging in cases of severe comminution and/or segmentation of the fibula. Restoration of fibular length is difficult without plating the fibula. However, when an external fixator is used in such a way that it incorporates and distracts the talus, it can indirectly restore fibular length by applying traction on the fibula through the intact talofibular ligaments.

Also, some overall symmetrical shortening of both the tibia and fibula is acceptable. In fact, shortening is preferred if restoration of the leg length by just a few centimeters means a more extensive surgery with devitalization of fracture fragments.

Wound closure

Meticulous soft-tissue handling is important throughout the surgery. The anterior joint capsule is closed, but the anterior tibial fascia is left open to prevent postoperative compartment syndrome.

Skin should be closed under no tension. The tibial wound is closed first. The preferred technique is an Allgöwer modification of the Donati stitch using nylon or Prolene suture and with the knots on the lateral flap of the tibial wound.

If necessary, the fibular wound can be left open and closed after a few days. Sterile dressings are used to cover incisions and wounds, but the pin sites for a frame are left open.

A well-padded, below-knee, posterior splint reinforced with 2 side splints is applied with the ankle held at 90°.

• Vascularity and sensation in the toes is documented in the immediate postoperative period.
• Postoperative analgesia is administered as required, usually with a patient-controlled device. Another alternative is the continuous popliteal block, which is also used for anesthesia at the time of surgery.
• The leg is kept elevated.
• Regular observations are made to ensure early detection of a compartment syndrome.
• Active exercises are encouraged, and antithrombotic measures are instituted as necessary.
• Patients are discharged home when comfortable.
• Patients should not bear weight on the operated leg until advised to do so.

Pin-site care requires daily irrigation and regular removal of any crust to prevent pin-site infection.

The incision sites are inspected at 1 week, and sutures are removed when incisions have healed, in approximately 2 weeks. The temporary splint is changed to a cast at this stage.

Depending on the stability and type of fixation, ankle range-of-motion exercises are started as soon as feasible.

Fracture alignment and healing are checked with serial radiography.

Weight bearing is not commenced until plain radiography demonstrates evidence of bony healing.

In patients with preexisting peripheral neuropathy, such as patients with diabetes mellitus for more than 10 years, prolonged protection in a removable cast or a boot is necessary to prevent late displacement, refracture, or both.

The rate of severe complications following open reduction and internal fixation of tibial plafond fractures ranges from 10-55%; some can lead to amputation.^{[8, 27]}

Soft-tissue complications include the following:

• Wound dehiscence
• Superficial skin necrosis at suture line
• Full-thickness skin loss
• Wound infection
• Damage to superficial nerves, neuroma, hypersensitivity, or chronic regional pain syndrome

Bony complications include the following:

• Pin-track infection
• Osteomyelitis
• Avascular necrosis of fragments devitalized by injury or surgery
• Malunion leading to deformities; these can be in single or multiple planes such as a varus, valgus, recurvatum, procurvatum, rotation, or shortening of the tibia and/or the fibula
• Articular incongruity
• Posttraumatic arthritis

Implant-related complications include the following:

• Loosening
• Failure or breakage of metal
• Infection

The outcome varies depending on the following factors:

• The severity of the injury to bone and soft tissues
• Delay from injury to presentation, especially in open fractures
• The patient's general condition and compliance
• Other associated injuries
• The surgeon's experience

Low-impact pilon fractures have better outcomes than high-impact pilon fractures. In general, good outcomes can be expected in approximately 60-80% of patients.^{[27, 28, 29, 30, 31]}

Many patients continue to improve for many years after the injury. The severity of the injury and the quality of the articular reduction frequently correlate with the development of arthrosis, but radiographic signs of arthrosis have only a weak correlation with clinical outcome^[32] .

Ankle fusions may be required in approximately 3-27% of patients with posttraumatic arthritis. Nonunion in the distal tibia can be treated with a fibula-pro-tibia plating and bone grafting procedure, as described by DeOrio and Ware.^[33] Ankle replacement is an option in selected individuals.

Minimally invasive plating techniques have been introduced in the past few years, and these help to minimize soft-tissue trauma and periosteal stripping.

Use of a CT C-arm intraoperatively may increase the accuracy of articular reduction.

Arthroscopy may be used intraoperatively to aid visualization of the reduction.^{[34, 35]}

Plating of the fibula is controversial (see Fibular plating in the Treatment, Intraoperative details section, above).

Outcomes following an innovative approach using staged posterior tibial plating for the treatment of Orthopaedic Trauma Association 43C2 and 43C3 pilon fractures in 9 patients with a separate, displaced, posterior malleolar fragment were compared by Ketz and Sanders to 10 patients with similar fracture patterns treated using standard anterior or anteromedial incisions with indirect reduction of the posterior fragment. All 19 patients were available for follow-up at an average of 40 months (range, 28-54 months). The average Maryland Foot Score and American Orthopaedic Foot and Ankle Society/Ankle & Hindfoot score for the first group was 86.4/85.2 compared with 69.4/76.4 for the later group.

The authors concluded that the addition of a posterior lateral approach offers direct visualization for reduction of the posterior distal fragment of the tibial pilon. Although the joint surface itself cannot be visualized, this reduction allows the anterior components to be secured to a stable posterior fragmentat a later date. This technique improved ability to subsequently obtain an anatomic articular reduction based on computed tomography scans and preservation of the tibiotalar joint space at a minimum 1-year follow-up.^[36]