“…have previously established that the posterior quadrants are relatively safe when compared to the anterior quadrants where the external iliac and obturator neurovascular bundle are at risk in the superior and inferior quadrants, respectively [ 8 , 17 , 28 , 29 ]. Injury to these vessels, particularly the external iliac, are known to occur [ 7 , 9 , 11 , 17 , 20 , 21 , [30] , [31] , [32] , [33] , [34] , [35] , [36] ]. Other authors have characterized the distance to danger from the acetabular surface, and in the anterior acetabulum, this distance is nearly universally <20 mm [ 28 ].…”