Throughout this treatment option illustrations of generic fracture patterns are shown, as four different types:
A) Unreduced fracture
B) Reduced fracture
C) Fracture reduced and fixed provisionally
D) Fracture fixed definitively
The modular external fixator is optimal for temporary use. It is rapidly applied without need for intraoperative x-rays and can be adjusted later.
The joint-bridging modular external fixator for distal tibial fractures consists of two partial frames, one along the tibia and one medial on the calcaneus or calcaneus and talus.
Details of external fixation are described in the basic technique for application of modular external fixator.
Specific considerations for joint-bridging modular external fixation, the distal tibia and the foot are given below.
Knowledge of safe zones and anatomy of the lower leg and the foot is essential for safe pin placement.
Drilling a hole in the thick tibial crest may be associated with excessive heat generation and there is a risk the drill bit may slip medially or laterally damaging the soft tissues. As the anteromedial tibial wall provides adequate thickness for the placement of pins, this trajectory is preferable. A trajectory angle (relative to the sagittal plane) of 20-60° for the proximal fragment and of 30-90° for the distal fragment is recommended.
Alternatively, to avoid the frame catching on the opposite leg, the pins may be placed more anteriorly. The drill bit is started with the tip just medial to the anterior crest, and with the drill bit perpendicular to the anteromedial surface (A). As the drill bit starts to penetrate the surface, the drill is gradually moved more anteriorly until the drill bit is in the desired plane (B). This should prevent the tip from sliding down the medial or lateral surface.
For the construction of the partial frame of the foot the following three options are used most frequently:
The fracture is reduced by manipulating the partial frame of the foot and ligamentotaxis. After checking correct reduction with image intensification, the reduced position is fixed by tightening all clamps.
Fixation of an associated fibular fracture adds stability and contributes to overall reconstruction. However, the possibility of additional soft-tissue injury must be considered before undertaking this step.
External fixation of distal tibial fractures is often extended to include the foot, to avoid an equino-varus deformity. Otherwise consider a splint to support the foot and ankle.
Proper pin insertion
To prevent postoperative complications, pin-insertion technique is more important than any pin-care protocol:
Various aftercare protocols to prevent pin tract infection have been established by experts worldwide. Therefore, no standard protocol for pin-site care can be stated here. Nevertheless, the following points are recommended:
Pin loosening or pin tract infection
In case of pin loosening or pin tract infection, the following steps need to be taken:
Before changing to a definitive internal fixation an infected pin tract needs to heal. Otherwise infection will result.
See patient 7-10 days after surgery for a wound check and for consideration to transition to definitive fixation to nail or plate internal fixation. X-rays are often taken to check the reduction.