Intramedullary Fixation Techniques for the Anterior Pelvic Ring.

Abstract

The superior ramus is an irregularly shaped, undulating, and curvilinear osseous structure that can provide an osseous conduit for intramedullary screws. A wide spectrum of variability between the curve and obliquity of the superior ramus osseous fixation pathway (OFP) exists in both the anteroposterior and the coronal planes. A detailed understanding of the osseous topography and how it correlates with fluoroscopic imaging is mandatory. Obtaining the correct intraoperative inlet and combined obturator oblique-outlet fluoroscopic views specific to each patient's anatomy is necessary for safe implant insertion. Intramedullary screws can be inserted in either an antegrade or a retrograde direction depending on a number of variables, including fracture location, the proximity of patient's external genitalia to the skin insertion side, and the possible impact of thigh girth on the surgeons hand position. Multiple screw insertion techniques are possible, but a simple and reproducible technique is described. The size and number of screws that can be inserted is variable, differs between surgeons, but is ultimately dependent on the cortical limits of the superior ramus OFP. Standard screw insertion techniques are successful in most patients. If the osseous corridor or external anatomy impedes standard insertional techniques, several modifications exist that can allow successful screw insertion. A thorough understanding of each patient's anatomy, injury, and precise surgical technique with the appropriate fluoroscopic views are required to safely place intraosseous intramedullary implants into the superior ramus OFP.