Objective To introduce a surgical protocol based on the location and orientation of the apex of the medial condylar fracture line for the treatment of Schatzker type Ⅳ tibial plateau fractures and report the preliminary effectiveness. Methods The clinical data of 18 patients with Schatzker type Ⅳ tibial plateau fractures underwent open reduction and internal fixation between March 2012 and April 2016 were retrospectively analysed. There were 6 males and 12 females, aged 36-74 years (mean, 45 years). The causes of injury included traffic accident in 2 cases, falling in 14 cases, bruise injury in 1 case, and crush injury of heavy object in 1 case. All cases were fresh closed fractures, without injury of nerves and blood vessels. According to sub type of Wahlquist tibial plateau type Ⅳ fracture classification, there were 1 case of type A, 5 cases of type B, and 12 cases of type C. The interval of injury and operation was 6-16 days (mean, 9.5 days). The location of the apex of the medial condylar fracture line was determined the surgical approach. After operation, reduction of tibial plateau fractures was evaluated by the DeCoster score evaluation criteria. The knee joint function was assessed by short Musculoskeletal Function Assessment (SMFA) score and Hospital for Special Surgery (HSS) score. Results The incisions all healed by first intension after operation without surgery related complications. All the patients obtained satisfactory exposure and reduction during operation. According to DeCoster score evaluation criteria, the results were excellent in 13 cases and fair in 5 cases. All the patients were followed up 12-30 months (mean, 18 months). X-ray films showed that all fractures healed at 10-16 weeks (mean, 12 weeks) after operation. There was no plate displacement, screw loosening, and other complications occurred during follow-up. At last follow-up, the SMFA score was 15-48 (mean, 28.5). The HSS score was 52-94 (mean, 81.1), and the results were excellent in 10 cases, good in 5 cases, fair in 2 cases, and poor in 1 case with an excellent and good rate of 83.3%; the main clinical manifestation was severe traumatic osteoarthritis symptom in 1 case with the fair result. Conclusion The surgical program should be developed based on the location and orientation of the apex of the medial condylar fracture line. Open reduction and internal fixation for treating Schatzker type Ⅳ fractures can achieve satisfactory effectiveness.