With the strategy of individualized surgical approach and manipulation of displaced fracture, based on the division into three zones based on the fibular head position, the accurate restoration of depressed articular surface could be achieved and the appropriate fixation could be attained with no reduction loss. The isolated posterolateral tibia plateau fractures show a rare incidence among the proximal tibia fractures, and can be easily overlooked. However, the accurate reduction of articular surfaced and the restoration of lower extremity alignment are important to avoid the progression of traumatic arthritis, thereby can require more complex treatment. Inadequate reduction of articular surface and tibial alignment result in functional deterioration and persisted pain at involved limb.
To date, there have been several studies that segmented the tibial plateau fractures and proposed perspective surgical approach and fixation techniques accordingly. Krause M et al. proposed the ten-compartment classification system, divided the entire tibial plateau into anterior and posterior compartments at first, then divided each anterior or posterior compartment into 5 sections . However, their segmentation was just to describe the fracture configuration, not to provide clinical assistance for operation. Luo et al. proposed a three-column classification that classifies the tibial plateau into medial, lateral, and posterior as the center point between the two tibial spines, and explained that surgical planning can be made according to the classification . However, they did not give more detailed explanations at posterolateral compartment.
Management of the tibial plateau fracture involving posterolateral compartment is technically challenging. There have been a few previous studies, suggested various surgical approaches and reduction techniques. Chih-Hsin et al. recommended the reduction and fixation using the anterior approach for posterolateral tibial plateau fracture because the posterior approach and fixation is risky to damage to the sural nerve, saphenous nerve, and popliteal arterial structures . And they reported that satisfactory articular reduction and postoperative functional results can be achieved without postoperative complications even with reduction and fixation using the anterior approach. On the other hand, Solomon et al. conducted a comparative study over the two-year follow-up period for the patients using the anterolateral approach and the patients using the trans-fibular posterolateral approach. The results showed that the patients who underwent surgery by visually identifying the fracture site using the trans-fibular posterolateral approach showed excellent postoperative results without formation of the articular step off in all patients compared to the patient group using the anterolateral approach with an average of 5.5 mm of large articular layer formation .
In this article, we proposed the sub-divided classification of the previous “three-column concept”  for the posterolateral tibial plateau fractures, and reported the clinical efficacy and safety of individualized approach and fixation according the classification. The posterolateral area of the tibial plateau is restricted by the fibula. Therefore, when surgeons make an attempt to access into most posterior area from anterior, they can encounter the difficulty to identify with direct vision and get to have troublesome to achieve the accurate articular reduction. Also, when surgeons consider the posterolateral portion of the plateau as a column, they can experience problems at the exposure of fracture site and fracture manipulation by fibular head and neurovascular structures around posterolateral knee.
We divided the posterolateral column to three zones based on fibular head position, and suggested different surgical approachs, patients’ position and fixation methods accordingly. Our strategy was effective in establishing the precise planning of the surgical approach and fixation methods. To apply the individualized approach, the entire tibial plateau should be identified in the axial or three-dimensionally reconstructed images of the preoperative CT scan. In the selected image, the anterior and posterior boundary of the fibula, tibial spine, and the posterior sulcus of tibia can be indicated. The initial impacted area and extended fracture line can be identified and it can be classified according to the three-zone classification. Surgeon can make a surgical planning using one or more individualized approaches according to the corresponding zone, not to be afraid of using additional approaches.
In this study, all posterolateral tibial plateau fractures were treated based on the three-zone classification, and different approaches were not applied for each zone. Merely, in the third zone, the most posterior part, the posteromedial approach was used [14–16]. The posterolateral approach presents the possibility of iatrogenic neurovascular damage such as the anterior tibialis artery , and venous bleeding during soft tissue exfoliation for fixation of distal screws often causes problems with hematoma and wound recovery . Also, later, it is difficult to remove the plate due to the formation of scar tissue and adhesion on the plate when the plate needs to be removed later. Meanwhile, the posteromedial approach can secure a sufficient surgical field and supply efficient buttressing force from the posterior fixation of the metal plate and screw. We kept to stand on that extended posteromedial approach would be more safe, easier and lesser burdensome than posterolateral approach to surgeon.
The postoperative results of the individualized approach to the posterolateral tibial plateau were excellent. In all patients, anatomical articular reduction was achieved and maintained without the reduction loss until the final follow-up. Postoperative imaging showed a good alignment within the normal range. In all patients, satisfactory clinical outcomes and no complication was observed during the follow-up period.
The findings of the present study are limited by its retrospective design with a limited number of samples. It was because that this study is designed only on the relatively rare isolated posterolateral tibial plateau fractures, which account for about 8% of patients with tibial plateau fractures. The surgical results can be influenced by operator experience and would be have an inter-operator technique variation. The current study also lacks a control group and further studies on posterolateral plateau fractures of the tibia may be required to elicit clinical results for a larger patient group.