"Virtual Lateral Wall" Technique to Overcome Nail Entry Pathway Errors and Optimize Success of Intramedullary Nailing in Pertrochanteric Fractures.

Abstract

Objective: The use of intramedullary implants for the treatment of pertrochanteric fractures is well-established. Nail entry pathway error is a common intraoperative challenge, particularly in pertrochanteric fractures with unstable greater trochanter fragment. This study introduces our innovative virtual lateral wall technique, which allows "lateral wall fracture" simplification from unstable to stable and effectively guides the reamer to create an accurate entry pathway for nail insertion in the treatment of pertrochanteric fractures.

Methods: A retrospective study was conducted on 12 consecutive cases of pertrochanteric fractures in our department between September 2022 and January 2024. The study population included three men and nine women, aged 68-90 years. Fractures were classified according to the AO/OTA system: one case of AO/OTA 1.3, one case of AO/OTA 2.2, and 10 cases of AO/OTA 2.3. All patients underwent surgical treatment with the proximal femoral nail anti-rotation (PFNA) implant. The surgical technique involved creating a "virtual lateral wall" using two 2.5-mm K-wires inserted into the greater trochanter from anterolateral to posteromedial to stabilize the unstable greater trochanter fragment and guide the nail entry. Intraoperative fluoroscopy was used to confirm the correct nail entry point and pathway. Surgical outcomes, including operative time, fluoroscopic exposure time, tip-to-apex distance (TAD), femoral neck-shaft angle, lag screw placement, and reduction quality based on the modified Baumgaertner criteria, were analyzed to evaluate the feasibility and efficacy of the technique. Complications were also recorded.

Results: The mean operative time was 33.3 ± 10.1 min, with an average blood loss of 58.3 ± 20.8 mL. Intraoperative fluoroscopy was used 13.8 ± 5.4 times, and the surgical incision length was 6.2 ± 0.7 cm. Postoperative radiographic evaluation revealed a femoral neck-shaft angle of 129.4° ± 5.5° and a tip-to-apex distance of 23.3 ± 4.4 mm. The lag screw was consistently positioned inferiorly within the femoral head. All cases achieved good reduction quality according to the modified Baumgaertner criteria. No severe complications, such as neurological or vascular damage, were observed during or after surgery.

Conclusions: The virtual lateral wall technique has demonstrated remarkable efficacy in preventing nail insertion complications in patients undergoing proximal femoral nail treatment for pertrochanteric fractures, particularly those characterized by an unstable lateral wall. This technique provides a reliable method for achieving accurate nail position, making it a valuable addition to the surgical management of complex pertrochanteric fractures with unstable greater trochanter fragment.