The intra- and interobserver reliability of the Tile AO, the Young and Burgess, and FFP classifications in pelvic trauma

INTRODUCTION: Several different systems of classification have been developed to understand the complexity of pelvic ring fractures, to facilitate communication between physicians and to support the selection of appropriate therapeutic measures. The purpose of this study was to measure the inter- and intraobserver reliability of Tile AO, Young and Burgess, and FFP classification in pelvic ring fractures. The Rommens classification system (FFP) is analyzed for the first time.

MATERIALS AND METHODS: Four reviewers (2 × senior pelvic trauma surgeon, 1 × resident, 1 × medical student) separately analyzed and classified 154 CT scans of patients with pelvic fracture. The Tile AO, the Young and Burgess, and the FFP classifications (subgroup with patients ≥ 60 years) were compared. Another blinded re-evaluation was carried out after 2 months to determine intraobserver reliability.

RESULTS: The overall interobserver agreement was fair for all classification systems (ICC: OTA 0.55, Young and Burgess 0.42, FFP 0.54). For specific categories, (e.g. type B or C fractures), there was a substantial agreement between the experienced surgeons (kappa: OTA 0.64, Young and Burgess 0.62, FFP 0.68). For inexperienced observers, there was a fair agreement in all systems (kappa: OTA 0.23, Young and Burgess 0.23, FFP 0.36).

CONCLUSIONS: All three classifications reach their maximum reliability with advanced expertise in the surgery of pelvic fractures. The novel FFP classification has proved to be at least equivalent when directly compared to the established systems. The FFP classification system showed substantial reliability in patients older than 60 years.