Effect of additional fixation in tibial plateau impression fractures treated with balloon reduction and cement augmentation

BackgroundIsolated tibial plateau impression fractures can be reduced through minimally invasive techniques using balloon inflation and cement augmentation. No evidence exists yet if an additional fixation at all and which method of fixation is necessary in the treatment of these fractures. The purpose of this study was to compare a locking plate and a screw raft for additional fixation after balloon reduction and cement augmentation in isolated tibial plateau impression fractures. Loss of reduction was subsequently analysed without additional fixation.MethodsLateral tibial plateau impression fractures were created in eight matched pairs of human cadaveric tibiae. Reduction was performed using a balloon inflation system, followed by cement augmentation. Additional fixation was performed with a lateral locking plate or a screw raft (four 3.5-mm screws). Specimens were cyclically loaded at 20-240 N, 20-360 N and 20-480 N. Subsequently, additional fixation was removed and the last cyclic interval (20-480 N) repeated. Loss of reduction was assessed by measuring subsidence of the subchondral bone.FindingsFractures treated with plate fixation exhibited less subsidence at higher loads compared with those treated with screw raft fixation (P < 0.05). Loss of reduction significantly increased after removal of the additional fixation.InterpretationThis experimental study suggests that loss of reduction can be minimised by using locking plate fixation after balloon reduction and cement augmentation in the treatment of isolated tibial plateau impression fractures.