Experimental study on treatment of acetabular anterior column fractures: applyment of a minimally invasive percutaneous lag screw guide apparatus

The aim of this study was to design a new minimally invasive percutaneous lag screw guide apparatus and to verify its adjuvant treatment of acetabular anterior column fracture on pelvis specimens. This guide apparatus was self-developed based on the principles of "two points form a line" and "Rectangle". Using C-arm fluoroscopy, this guide apparatus was used to conduct minimally invasive percutaneous lag screw internal fixation of acetabular anterior column fractures. Ten hollow lag screws were placed into 5 pelvis specimens. Result showed no sign of any screws puncturing the cortex or entering into the hip joint on radiological assessment. The cross-section reconstructed vertical distance to the screw, on the cross-section acetabular notch and the cross-section of the screw where the distance of between the screw and the iliopectineal line's arc roof was at its shortest, indicate that at all points (T, R-r) under the line with an inclination of 1 (namely T = R-r) the screw is within the cortex and does not puncture the acetabula anterior column or enter into the hip joint. We may conclude that this self-developed guide apparatus solves the screw precision problem during the treatment of acetabular anterior column fractures through a minimally invasive percutaneous lag screw.