All cases of displaced tibial plateau fractures treated by open reduction and internal fixation at two university hospitals over a 3-year period were retrospectively reviewed. There were 47 fractures in 45 patients. Rigid fixation to allow early motion was the goal in all cases. There were 3 AO type I (wedge) fractures, 20 AO type III (wedge/depression) fractures, and 24 AO type IV (comminuted/bicondylar) fractures. Cases were classified into three groups depending on the amount of hardware used to obtain fixation (a single buttress plate, group 1; a buttress plate and interfragmentary lag screws, group 2; or medial and lateral buttress plates with or without lag screws, group 3). In group 1, there were 20 fractures and no instances of deep-wound infection or postoperative ankylosis. In group 2, infection occurred in 6 of 19 fractures (32%), all of which also developed significant ankylosis including 1 patient who underwent arthrodesis. In group 3, 7 of 8 (87.5%) knees became infected, and the patients experienced other devastating complications, including ankylosis (n = 3), arthrodesis (n = 2), knee disarticulation (n = 1), and above-knee amputation (n = 1). Patients whose knees became infected underwent an average of five subsequent surgical procedures. These results suggest that patients with comminuted tibial plateau fractures requiring either two buttress plates or a single plate with additional interfragmentary lag screws would probably be better managed by either non-operative treatment or limited internal fixation.