To develop a reliable classification system based on the anatomical characteristics of distal femoral fractures combined with dislocations, thereby providing a reference for clinical management.

Patients with femoral condylar fractures and knee dislocations caused by trauma, who had complete imaging data (X-ray and CT), were included between August 2012 and January 2024. Those with pathological or old fractures, unclear or missing imaging data, or incomplete follow-up records were excluded. To establish the fracture-dislocation classification system, a research team consisting of one director and nine attending physicians in orthopedic trauma reviewed and discussed 90 cases, ultimately developing a new classification system. Inter- and intra-observer reliability was determined using Fleiss’ kappa and Cohen’s kappa tests by ten independent evaluators, leading to the proposal of a standardized clinical management protocol.

The newly established classification system categorized cases into three types. Type A: distal femoral fracture with patellofemoral joint dislocation; type B: distal femoral fracture with tibiofemoral joint dislocation; type C: distal femoral Hoffa fracture with knee joint dislocation.The mean intra-observer agreement was κ= 0.923 among the ten research team members, and the mean intra-observer agreement was κ=0.931 among the ten evaluators. Based on the new classification system, a standardized clinical diagnostic and treatment workflow was established.

The study demonstrates that the new classification system for distal femoral fracture-dislocations exhibits high inter-observer reliability. By integrating both fracture and dislocation components, this system effectively addresses injury patterns that traditional classifications fail to categorize, thereby assisting clinicians in optimizing workflow and selecting appropriate treatment strategies.