Frequency of tibial plateau fracture combined with dislocation and imaging features of medial or posteromedial fragments

Objective To evaluate the incidence and imaging features of tibial plateau fracture combined with dislocation. Methods A total of 298 patients with intact imaging data treated for tibial plateau fracture from December 2012 to June 2014 were analyzed retrospectively. Tilt angle of medial fragment fracture line, ratio of width of medial fragment to total plateau, surface area percentage, fragment height, and major displacement were measured on CT images using picture archiving and communication system (PACS). Results Eighteen patients (6.0%) had tibial plateau fractures combined with dislocation, with tilt angle of medial or posteromedial fragment fracture line of (62.1±14.1)°. Eleven patients (61%) had split of the medial tibial plateau with surface area percentage of (46.3±2.5)%, fragment height of (43.9±6.2)mm, and major displacement of (5.3±2.1)mm.Seven patients (39%) had posteromedial fragment fracture with surface area percentage of (25.1±5.7)%, fragment height of (40.0±10.1)mm, and major displacement of (4.8±6.45)mm. Conclusions Fracture line of fracture-dislocation tibial plateau fracture is much often through the eminence or located at the lateral eminence with large medial or posteromedial fragments. Surgical approaches and directions of nailing should be considered properly according to the morphological characteristics. Key words: Tibial fractures; Dislocations; Radiography