How much is too much? A guide to appropriately bending ball tip guide wires when using intramedullary nails for the treatment of lower extremity long bone fractures

IntroductionThis study was to determine the angle of bend that can be placed in a ball-tip guide wire while still allowing passage of reamers and nails of several commonly utilized nailing systems.MethodsBall-tip guide wires, opening reamer tips, femoral nails, and tibial nails were collected from several manufacturers. Guide wires were incrementally bent 3 cm from the tip and passed through the reamer tip, tibial nail, and femoral nail until unable to pass.ResultsAll systems tested demonstrated that the reamer, with its relative smaller diameter cannula as compared to the nails themselves, determined the smallest tolerable bend to be able to pass the bent guide wire. The bend angle tolerated by reamer tips was on average 7° (4–9°). The bend angle tolerated by femoral nails was more consistent between the tested systems and was on average 15.5° (12–18°). The bend angle tolerated by tibial nails had the most variability between manufacturers and was on average 16° (13–21°).DiscussionKnowing the degree of guide wire bend which is tolerated can save time in equipment preparation as well as allow one to pre-bend the guide wire and know the intramedullary nail and/or reamers will likely pass. We hope the information provided in this work increases awareness of the potential technical issues with guide wire over-bending and that surgeons may err on the side of minimizing the bend in order to save time in the OR, decrease frustration and eliminate intraoperative complications that can occur.