IMAGING AND ANATOMY

After appropriate radiographs, computed tomography (CT) is important in operative planning (Table 66-1). Tornetta and Gorup¹ have shown that their operative plan was altered in 64% of patients, with additional information about fracture pattern gained in 82%, underlining the importance of appropriate imaging. Understanding the anatomy of the fracture should allow the development of appropriate steps in fracture fragment approach and reduction, improving surgical technique and ultimately outcome.

Recent work from Bristol² documents 126 pilon fractures, and defines 6 distinct fracture fragments (anterior, posterior, medial, anterolateral, posterolateral, and die-punch) and 2 fracture families (sagittal and coronal). Within each fracture group there was progression from a simple to a more complex type with increasing transfer of energy. Interestingly, a pilon fracture with an intact distal fibula was eight times more likely to have a functional disruption of the tibiofibular joint (separated lateral tibial fragments), and if not recognized, resulted in continued instability and its associated complications. The reproducibility of this fracture description was found by Topliss and colleagues² to be superior to the AO and Ruedi and Allgower’s³ classification concerning interobserver and intraobserver agreement. The authors conclude that the sagittal family fractures occur after high energy, with varus angulation in young-er patients, whereas the coronal fractures occur with valgus angulation in older patients after less severe trauma. This work has implications for surgical approach, reduction of fracture fragments, and choice of implant.

TREATMENT OPTIONS

Pilon fractures, although not common, do cause considerable debate and controversy as to what surgical methods should be used and the timing of surgery in relation to soft-tissue status. The treating surgeon is faced with two competing priorities. The first priority is to achieve an anatomic reduction of the fracture with fixation sufficiently secure to allow early movement, and the second is to minimize iatrogenic disruption of the vulnerable soft-tissue envelope.

It has generally been accepted that for displaced pilon fractures, surgical management with reduction and fixation is appropriate as long as there is no contraindication to surgical intervention for the individual patient (Level IV).

The surgical strategies can be divided into three broad subsets:

The optimal management of these difficult injuries remains controversial. The staged protocol has shown acceptable results and has gained a substantial level of support. Indeed, we are aware that the faculties at some recent international conferences and instructional courses have suggested that it is the only acceptable treatment option.

EVIDENCE

Several studies have been published that aim to compare the differing treatment modalities for pilon fractures, but all have their limitations when conclusions are drawn from limited sample size and variable patient conditions (Table 66-2).

Blauth and colleagues⁴ retrospectively studied 51 patients. They had 3 treatment groups: primary ORIF (15 patients all with closed injuries), definitive ExFix with or without limited internal fixation (28 patients), and temporary ExFix with or without limited internal fixation followed by delayed minimally invasive medial plating (8 patients). The incidence of wound infections did not differ significantly among the three groups. The range of ankle movement was greater in the two-stage treated group compared with the others. These patients also had less pain, more frequently continued working in their previous profession, and had fewer limitations in their leisure activities. On the basis of these findings, the authors recommend a two-stage procedure. However, the sample size is small in this retrospective review, and the groups are not well matched; therefore, definitive conclusions cannot be made.

Similar work by Pugh and coauthors⁵ retrospectively assessed 60 pilon fractures. Again, there were 3 broad groups: 24 patients treated with ORIF, 21 patients treated with an ankle-spanning half-pin ExFix, and 15 patients with a single-ring hybrid ExFix. The severity of injuries was similar in all groups. No significant difference was reported in complications between groups, but a greater number of malunions occurred in fractures treated with ExFix compared with ORIF (P = 0.03). These findings were uninfluenced by whether the fracture was open or closed, was bone grafted, or had an associated fibula fracture stabilized. The authors conclude that external fixation had a lower risk for deep infection but a greater risk for malunion than did ORIF. No randomization, long-term follow-up, or functional outcome was performed in these patients.

A surgeon randomized, prospective study⁶ evaluated 39 patients. Nineteen patients underwent ORIF of both tibia and fibula, and 20 patients had ExFix with or without limited internal fixation. The authors aimed to compare the rates of complications, the radiologic results, and the functional results between the two groups. In the ORIF group, there were 28 additional operations in 7 patients with 15 major complications compared with 5 additional operations in 4 patients with 4 major complications in the ExFix group. They found that nonvalidated clinical score (pain and range of motion) did not correlate well with type of fracture, and there was also no significant difference between treatment groups. The conclusion was that ExFix is a satisfactory method of treatment associated with fewer complications than ORIF. However, of note is the timing of surgery in the ORIF group, and this point should be highlighted. Operating in the presence of severe intradermal edema or fracture blisters can further compromise damaged soft tissues. On average, patients were operated on days 3 to 5, when soft-tissue swelling was well established. Therefore, it may well not be technique related but timing dependent.

This point has been examined by work from Sirkin and colleagues.⁷ They retrospectively analyzed 56 pilon fractures (34 closed and 22 open fractures) from a single institution. All patients underwent immediate ORIF of the fibula and closed reduction with spanning ExFix for the distal tibia. Formal ORIF of the tibia was performed when soft-tissue swelling had subsided, on average, 14 days after injury. By following a staged protocol, they demonstrated that ORIF could be performed semielectively with a low risk for wound problem in both open and closed injuries. However, no functional outcome scoring of results with this effective soft-tissue–preserving procedure exists.

Similar retrospective work from Florida (Patterson and Cole⁸