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Three-Dimensional Computed Tomography Reduced Fixation Failure of Intramedullary Nailing for Unstable Type of Intertrochanteric Fracture.

To the Editor: We congratulate Dr. David J. Ciufo1 and his team for presenting an interesting article entitled “Risk Factors Associated With Cephalomedullary Nail Cutout in the Treatment of Trochanteric Hip Fractures.” We agree with their finding that the most strongly associated risk factor was fracture of the lateral wall noted on preoperative imaging. They published the first study to specifically report the significance of lateral wall integrity and its relationship to fixation cutout in cephalomedullary nailing. It is well known that fractures of the lateral wall, regardless of presence preoperatively or postoperatively, are associated with reoperation for extramedullary fixation. Iatrogenic lateral wall fracture can cause fixation failure and cutout complications requiring a salvage procedure (Fig. 1). We use 3-dimensional computed tomography (3D CT) preoperatively to classify the lesser trochanteric fragment and define the ideal entry point for cephalomedullary nailing. Futamura et al2 reported a new classification according to 3D CT–based morphology of the lesser trochanter. There were 4 subgroups as typical fractures associated with each type of intertrochanteric fracture, including (1) fracture across the intertrochanteric line; (2) bone fragment of the lesser trochanter (the disruption of posteromedial support); (3) bone fragment of the femur greater trochanter (the disruption of posterolateral support); and (4) banana-shaped fragment, including the lesser trochanter and greater trochanter in continuity. We found that patients with subgroup type 2 and 4 benefit from a modified wiring technique, which was first introduced by Lee et al.3 This technique addresses the advantages of lesser trochanteric fixation including the posterolateral fragment with good clinical results in unstable intertrochanteric fractures.4 It theoretically has many advantages, including increasing stability intraoperatively during intramedullary nailing and maintaining reduction postoperatively (Fig. 2). It is difficult to decide the appropriate entry point for comminuted intertrochanteric fractures using plain radiographs. Therefore, 3D CT is useful for planning the reduction technique, ideal entry point, and nail placement. In the 4 subgroups mentioned above, the entry point of type 3 intertrochanteric fracture, which accounts for the suitable implant position, can be determined via 3D CT. We found that when surgically repairing unstable intertrochanteric fractures with lesser trochanter comminution using the proximal intramedullary nailing method, the modified wiring technique reinforced the fixation at the fracture site. Thus, through this technique and 3D CT imaging, both stable fixation of the lesser trochanter and more rapid bone union were obtained.