This is the first prospective study of combined lateral peripatellar and posteromedial approaches in the treatment of Schatzker type IV tibial plateau fractures involving posteromedial plane. The present study showed that the approach acquired satisfying clinical outcomes. All patients had clinical outcomes rated as excellent or good. The motion ranges of the knee joint were nearly normal levels. All patients achieved bone union on time.
The main goals in the treatment of tibia plateau fractures include anatomic reduction of articular surface, maintenance of normal knee alignment, provision of knee stability and restoration of a painless range of motion and function [4, 11-13]. Schatzker type IV tibial plateau fractures involving posteromedial plane remain difficult, because they usually accompany with meniscus and ligaments injuries. Two approaches have been applied to expose the type of fracture. However, either of them has its limitations. The medial approach with a medial parapatellar hasn’t given an adequate exposure of medial plateau, and it is very difficult to fix the posteromedial fragment if we don’t make an extensive dissection of the soft tissue. The posteromedial approach allows an wider exposure of posteromedial fragment for the fixation of the buttress plate[14-16]. However, it is unable to elevate and repair the lateral meniscus that trapped in the fracture line due to the limited visualization. Stannard et al reported that there was a 49% meniscus injury during high-energy tibial plateau fractures, and the incidence of lateral meniscus injury was more than medial meniscus injury . Barrow et al reported the incidence of meniscus injury was 25% in Schatzker type IV tibial plateau fractures of their study. Therefore, in order to solve the limitation of the two approaches, we designed the combined lateral peripatellar and posteromedial approaches. It could not only aid in the anatomic reduction of articular surface, but also repair the injured meniscus.
The incidence of injured meniscus was 44.44% (8/18) in our study. We repaired all the injured meniscuses when we achieved the adequate fixation of the fracture by dual plates. We believed that it was very important to repair these injured meniscuses, because they could allow patients to perform the early functional exercises and be beneficial to restore the normal ranges of knee motion. There were no serious complications in our study. Only 5.56% (1/18) patients had transient palsy of saphenous nerve and 5.56% (1/18) patients had superficial wound infection, and finally they were all cured. We thought we could overcome these complications as long as we pay more attention to them. The main advantage of our approach was that it could overcome the limited visualization to aid in the anatomic reduction of articular surface and repair associated injured menisci at the same time. Especially in the case of failure of restoring the width of plateau through the medial or posteromedial approach (Figure 3), we should consider if the injured meniscus is trapped in the fracture line or not and add a lateral peripatellar approach as viewing window to aid in congruent joint reduction. However, the view of medial tibial plateau through the lateral window is very limited for the middle and posterior third of the medial meniscus.
In our experience, some important aspects should be paid. (1) We should evaluate carefully the fracture and the soft tissue envelope based on specific conditions of the patient. Handing the soft tissue properly in this region is critical to successful treatment. (2) Computed tomography (CT) is necessary before the operation. Magnetic resonance imaging (MRI) is recommended, because it can provide information with regard to associated meniscus and ligaments injuries that may affect the treatment plan. (3)We should try our best to repair the injured meniscuses. There are two types of fracture combined with cruciate ligament injury. The first is the avulsion of cruciate ligament. Ligament's bony avulsions should be repaired at the time of the internal fixation, acutely, thus promoting better prognosis due to direct bone to bone healing. The second is the rupture of the cruciate ligament. We should repair it through arthroscopy after the healing of fracture. As for MCL (medial collateral ligament, MCL) or LCL (lateral collateral ligament, LCL) injury, we also shouldn't add an additional to repair the injured MCL or LCL, and we need add a knee plaster to protect the injured ligaments, because MCL or LCL damage is often incomplete. (4) In our approaches, the distance between the two skin incisions should be more than 7cm in order to avoid the necrosis of the skin. (5) The incision of the lateral peripatellar approach should be small, because it just is a viewing window to aid in the treatment of the fracture.
The main strength of our study is that all the operations were performed by the same orthopaedic surgeon, and it can avoid the differences caused by different surgeons' preference and experience. The type of the study is prospective. However, there are some limitations. The number of patients is relatively small, and control group isn’t included in our study. Therefore, the potential biased on our outcomes may be exist, and more patients need to be included in the future study to verify the effectiveness of this procedure and overcome the limitations of our current outcomes.