[Establishment of Schatzker classification digital models of tibial plateau fractures and its application on virtual surgery].

OBJECTIVE: To explore the establishment of Schatzker classification digital model of tibial plateau fractures and its application in virtual surgery. METHODS: Proximal tibial of one healthy male volunteer was examined with 64-slice spiral computed tomography (CT). The data were processed by software Mimics 10.01 and a model of proximal tibia was reconstructed. According to the Schatzker classification criteria of tibial plateau fractures, each type of fracture model was simulated.Screen-captures of fracture model were saved from different directions.Each type of fracture model was exported as video mode.Fracture model was imported into FreeForm modeling system.With a force feedback device, a surgeon could conduct virtual fracture operation simulation.Utilizing the GHOST of FreeForm modeling system, the software of virtual cutting, fracture reduction and fixation was developed.With a force feedback device PHANTOM, a surgeon could manipulate virtual surgical instruments and fracture classification model and simulate surgical actions such as assembly of surgical instruments, drilling, implantation of screw, reduction of fracture, bone grafting and fracture fixation, etc. RESULTS: The digital fracture model was intuitive, three-dimensional and realistic and it had excellent visual effect.Fracture could be observed and charted from optional direction and angle.Fracture model could rotate 360 ° in the corresponding video mode. The virtual surgical environment had a strong sense of reality, immersion and telepresence as well as good interaction and force feedback function in the FreeForm modeling system. The user could make the corresponding decisions about surgical method and choice of internal fixation according to the specific type of tibial plateau fracture as well as repeated operational practice in virtual surgery system. CONCLUSION: The digital fracture model of Schatzker classification is intuitive, three-dimensional, realistic and dynamic. The virtual surgery systems of Schatzker classifications make the virtual surgery training more normalized, programmed and standardized.In addition, virtual surgery system can serve as a new tool for preoperative planning and surgeon-patient interactions.

[Surgical approaches for intertrochanteric fractures in elder patients].

OBJECTIVE: To conduct long-term follow-ups on the efficacies of surgical approaches for intertrochanteric fractures in elder patients. METHODS: The outcomes of intertrochanteric fractures in 402 elder patients undergoing different surgical procedures during 2005 to 2009 were reviewed. The modified classification of Singh index, detailed surgical contraindications and improved functional scoring system specialized for intertrochanteric fracture were included. Among these, type I to IV had 17 cases (4%), 49 cases (12%), 187 cases (72%), 48 cases (12%). The follow-up period was 1 - 5 years. The orthopedic complications, rehabilitation duration and functional scores were reviewed. RESULTS: Most patients achieved self-care at 1 month post-operation. The failure rate of internal fixation was 5% and infection rate 1.9% in hemiarthroplasty. type I to IV had 70.6% and 100.0%, 85.7% and 86.7%, 85.4% and 92.0%, 72.9% and 87.5% cases showed excellent or good outcomes at 3 month and 1 year. During a follow-up period of 5 years, there was no occurrence of prothetic loosening or excessive wear of acetabular. CONCLUSION: A rational selection of surgical approaches may markedly reduce the failure rate of internal post-operative fixation and shorten the rehabilitation period. And the long-term follow-up outcomes are satisfactory.