Pilon fractures: A new classification system based on CT-scan

Abstract

Actually, pilon fractures are classified according to AO and Ruedi Allgower classification systems based on X-rays. These classifications are less reproducible and do not provide necessary information for proper surgical planning. Aim of the study is to (1) propose a new classification system based on CT scan; (2) to check the prognostic value of this classification and (3) to evaluate its reliability and (4) reproducibility. We retrospectively reviewed 71 cases of pilon fracture. All fractures were classified according to AO, Ruedi Allgower and new proposed classification system by 5 surgeons. Clinical and radiographic evaluation were performed at a mean follow-up of 36 months. Cohen's K value was calculated in order to evaluate the interobserver and intraobserver agreement. Sixty-four of 71 fractures healed. Average AOFAS score was 91,7±7,8 in the Type I of new classification proposed, 87,7±7,8 in the Type II, 82±18,6 in type III, and 67,2±20,9 in type IV. Using the AO classification system the average K weighted value among the five reviewers was 0,51; using Ruedi Allgower classification it was 0,50 and using the new classification system it was 0,88 (p<0.0005). This study demonstrated that the new classification system is prognostic, reliable and reproducible. Moreover it provides a new treatment-oriented classification for this challenging fracture which affect the quality of life of the patients more than chronic diseases like diabetes and coronaropathy or pelvic fractures.

Keywords: CT scan classification; Interobserver agreement; Pilon fractures; Reliability; Treatment-oriented classification.