Functional Outcomes of Patients Undergoing Anterolateral versus Anteromedial Approaches of the Ankle for Pilon Fractures Tyler J. Jenkins BS, Michael Khazzam MD, Gregory J. Della Rocca, MD, PhD, Allison M Wade MD, Yvonne M. Murtha MD, and Brett D. Crist MD Introduction: Pilon fractures involve the distal tibia and are often associated with a corresponding fibula fracture. These fractures mainly result from high energy accidents such as falling from a high surface or motor vehicle accidents. Pilon fractures continue to challenge even the most experienced orthopedic traumatologists. Many studies have been published showing the high incidence of complications as well as the difficulties in treating this fracture. The current treatment protocol for open reduction and internal fixation (ORIF) of pilon fractures uses a two-staged approach and has been shown to decrease the risk of complications compared to primary ORIF. This two-staged protocol involves external fixation of the tibia and usually ORIF of any fibula fracture (Fig 1B). Once the swelling and soft-tissue injury resolve (10-21 days) the second stage is completed with definitive open reduction and internal fixation of the tibia(Fig 1C). Careful preoperative planning is crucial to achieving desirable clinical outcomes, but currently the literature does not reach a consensus on which surgical approach is optimal. This study examines the functional outcomes of two of the most common surgical approaches for pilon fractures, the traditional anteromedial approach and the more recently described anterolateral approach. The anterolateral approach is thought to produce better outcomes because of the greater amount of visualization in the articular surface and greater soft-tissue coverage for the implant. Methods: 82 potential subjects were identified to have been treated for pilon fractures of the distal tibia between August 2005 and July 2009 at a level 1 trauma center. Of these patients 39 agreed to be subjects in our study and were asked to fill out the Musculoskeletal Functional Assessment (MFA) and Foot Function Index (FFI) by a telephone interview. This data was then analyzed according to guidelines for each survey. Both scales are assessed on a scale with 100 being maximum dysfunction and 0 being minimum dysfunction. Average scores for each group were obtained for the MFA and FFI. In addition the average duration of time from surgery to survey completion and the average pilon fracture classifications for each group were obtained. Table 1 explains how the numerical average of each group’s fracture classification was obtained. The results were then compared using a paired student t-test. Results: 23 of the 39 patients had undergone fixation using the anterolateral approach and had an average AO/OTA pilon fracture classification of C2-C3. 14 of the 39 patients had fracture fixation using the anteromedial approach and had an average AO/OTA pilon fracture classification of B3-C1. 2 of the 39 patients in the study had fracture fixation with both the anterolateral and anteromedial approach with an average fracture classification of C2-C3. The was no significant difference (p=0.9270) in MFA scores between the anterolateral and anteromedial groups (35.26 AL and AM) but the patients that had both approaches had a significantly worse outcome of 40. Likewise there was no significant difference (p=0.9170) for in FFI scores between the groups (45.56 and respectively) and the group that had both approaches had a higher value of AL (23)AM (14)AM & AL (2) Total MFA Score Patient Rating Subscore Move Stand. Score Fine Stand. Score Home Stand. Score ADL Stand. Score Sleep Stand. Score Leisure Stand. Score Relationship Stand. Score Cognition Stand. Score Emotion Stand. Score Job Stand. Score FFI Total Score FFI Pain Subscore FFI Disability Subscore FFI Activity Limitation Time From Surgery to Survey3.28 yr3.54 yr3.35 yr Average Fracture ClassificationC2-C3 (2.580)B3-C1 (1.90)C2-C3 (2.50) Table 2: Functional Outcome Comparison between the Anterolateral and Anteromedial Approaches to Pilon Fracture Fixation Pilon Fracture AO Morphological Classification Numerical Value A11/3 A22/3 A33/3 B14/3 B25/3 B36/3 C17/3 C28/3 C39/3 Discussion: The outcomes of the two different approaches did not produce a statistically different outcome (p-values of.9270 for MFA comparison and.9170 for FFI comparison). Yet the significantly higher fracture classification of the anterolateral approach patients (C2-C3 compared to B3-C1) would be expected to produce worse clinical outcomes than the anteromedial group. The improved long-term functional outcomes from the anterolateral incision may result from the greater amount of soft tissue coverage for the implant and better visualization of the articular surface. The improved soft- tissue coverage decreases the incidence of soft tissue complications. Visualization enhancement of the articular surface allows easy access to the distal tibia and tibiotalar joint where all class C fractures appear. It is also worth noting that a majority of AO/OTA classified C3 fractures occur on the anterolateral side of the tibia and therefore this approach will yield better visualization for the worst possible classified pilon fractures. Although the sample size may be relatively small and a larger series may prove significant differences, we can conclude that the anterolateral approach does improve long-term functional outcomes of patients with pilon fractures. Although fracture pattern and soft tissue coverage are the primary issues that determine surgical approach, it appears that in C-type pilon fractures that have anterolateral comminution, the anterolateral approach will produce functional outcomes similar to less complicated pilon fractures addressed through the traditional anteromedial approach.