Vertical femoral neck fractures in young adults: a closed fixation strategy using a transverse cancellous lag screw

Abstract

Vertical femoral neck fractures (Pauwels type III classification) in young adults generally occur as a consequence of high-energy trauma and are frequently seen in association with multiple injuries. Considering the controversies regarding the optimal fixation for this fracture, our aim was to evaluate the clinical outcome of a closed fixation strategy for vertical femoral neck fractures in young adults using two parallel and one transverse cancellous lag screws. This was a single-surgeon, prospective study including 20 young adults with average age of 38.75 years (range 18-59 years) with a high-energy Pauwels III femoral neck fracture. Closed reduction and internal fixation with three cancellous lag screws were performed. The first screw was inserted crosswise to avoid further shear forces. Second and third parallel screws were placed above the lesser trochanter and centrally on the greater trochanter, respectively. Clinical outcomes were assessed by comparing postoperative and final follow-up radiographs 24 months post-injury. Eleven patients had an isolated vertical femoral neck fracture. Of these, five had further femoral neck comminution. Nine patients had an associated ipsilateral femoral shaft fracture. All fractures were displaced at the time of the first radiological evaluation. Closed reduction quality was considered excellent or good in 15 patients. After 24 months, bone union was achieved in 16 cases. Osteonecrosis of the femoral head developed in association with two fractures, and a nonunion developed in association with two fractures. We conclude that vertical high-energy femoral neck fractures can be treated successfully with internal fixation with two parallel cancellous lag screws positioned above the lesser trochanter and a third screw inserted centrally on the greater trochanter at an angle perpendicular to the fracture line.