Biomechanical Studies Of The Columbar Fractures With Transpedicular Grafting

Objective:To study the biomechanical effects on the fracture segment and adjacent segment of columbar vertebral compressive fracture with transpedicular grafting.Methods:18 cadaver thoracolumbar spine specimens were randomly divided into 6 group:Normal contral; Vertebral compressive fracture; Vertebral compressive fractures with interbody fusion via transpedicular self bone grafting ; Vertebral compressive fractures with transpedicular PMMA cement grafting ; Vertebral compressive fractures with self bone grafting and reduction fixation . Vertebral compressive fractures with PMMA cement grafting and reduction fixation . Four simulations (axial compression,flexion,extension and lateral bending) were applied in the biomechanical testing machine. Data of the rigidity and stress of the fracture segment and adjacent segment were recorded and analyzed.Result:Transpedicular self bone grafting and PMMA cement grafting could enhance the stability index of the fracture segment(P<0.05). Meanwhile they make the tiny tendency that the adjacent segment rigidity degrade and stress raise, but it is not significant difference(P>0.05);Internal fixation could enhance the stability index of the fracture segment more obviously(P<0.05), and make the adjacent segment rigidity degrade and stress raise significant(P<0.05).Conclusion:Transpedicular self bone grafting and PMMA cement grafting could enhance the stability of the fracture segment,and has little effect on the adjacent segment;Internal fixation could enhance the stability of the fracture segment more obviously,and has disadvantageous effect on the adjacent segment .