Computer-Assisted Navigation for Intramedullary Nail Fixation of Intertrochanteric Femur Fractures

There are approximately 250,000 hip fractures in the US every year, and intertrochanteric (IT) fractures (fractures that occur just below the femoral head) account for nearly half of these fractures. The use of intramedullary (IM) nails for fixation of IT femur fractures has become a well-accepted and increasingly more common procedure among orthopaedic traumatologists, and is standard of care at our institution. While advancements in intramedullary nail fixation have made it a relatively efficient procedure, the placement of the lag screw into the femoral head still remains a challenging step in the procedure. Inaccurate placement can lead to screw cut-out, one of the most commonly reported complications with IM nail fixation. Previous work has shown that the lag screw position is an important factor in reducing screw cut-out. This step of the procedure can be time demanding and often requires several intraoperative radiographs for accurate placement. Recently developed computer-assisted navigation systems provide surgeons with the ability to track screw placement in real-time. This could allow for improved screw placement and potentially reduce radiation exposure to the patient and surgeon. To date, the potential advantages of computer-assisted navigation have not been examined. The primary objective of this study is to examine whether the use of Stryker's ADAPT computer-assisted navigation for Gamma nail fixation can result in improved lag screw placement. The secondary objective is to examine whether the use of the ADAPT for Gamma nail fixation can reduce intraoperative radiation exposure.Our hypothesis is that there is a difference in the lag screw placement (i.e. tip to apex distance measurement) between procedures using the ADAPT system versus the conventional technique for Gamma nail fixation. Additionally, we hypothesize that there is a difference in radiation exposure (i.e. fluoroscopy time) between procedures using the ADAPT system versus the conventional technique for Gamma nail fixation.

Patients that receive intramedullary nail fixation with use of the Stryker ADAPT computer-assisted navigation system

Patients that receive conventional technique intramedullary nail fixation without use of the Stryker ADAPT computer-assisted navigation system

Inclusion Criteria: Patients undergoing hip fracture fixation with a Gamma Nail by one of four orthopaedic trauma surgeons at William Beaumont Hospital Royal Oak Diagnosis of an intertrochanteric femur fracture (AO Classification 31-A1,A2) Low energy mechanism of injury (i.e. fall, twist) Exclusion Criteria: Minors (less than 18 years) Pregnant Have a high energy mechanism of injury (e.g. motor vehicle accident, fall from height) Have an open fracture (i.e. the skin is broken at the fracture site), or Present with multiple injuries to the ipsilateral lower extremity

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