The proximal femur nail antirotation: an identifiable improvement in the treatment of unstable pertrochanteric fractures?

Background: The optimal surgical treatment of patients with an unstable extracapsular proximal femoral fracture is yet to be found. From the biomechanical point of view, the use of an intramedullary device in combination with a dynamic femoral head/neck stabilization implant seems an optimal technique. One of these intramedullary devices, the Proximal Femoral Nail (PFN), has several drawbacks in practice. The Proximal Femur Nail Antirotation (PFNA) has been designed to address these. We hypothesized that the placement of one femoral head/neck fixation device in the PFNA would improve positioning of the implant in the femoral head compared with the PFN and reduce the number of reoperations in both short and long term.

Methods: We followed 157 consecutive patients with unstable trochanteric fractures (Arbeitsgemeinschaft für Osteosynthesefragen classification 31.A.2 and A.3) treated with a PFN or a PFNA for 1 year. The radiologic position of the implant was evaluated, and the postoperative local and systemic complications were registered.

Results: The position of the femoral head/neck stabilization implant was "good" in 39 (44.8%) patients in the PFN group and 23 (32.9%) patients in the PFNA group; the position was "acceptable" in 30 (34.5%) versus 33 (47.1%) patients, and in 18 (20.7%) versus 14 (20%) patients, the position was "poor" (p = 0.277). Because of implant-related complications, three patients in the PFN group and four patients in the PFNA group needed an early reoperation (p = 0.136). A late reoperation because of implant-related complications was performed in 13 patients in the PFN group and in three in the PFNA group (p = 0.016).

Conclusions: This study shows that osteosynthesis with the PFNA does not improve the position of the implant in the femoral head compared with the PFN. However, the risk of a secondary complication and the necessity of a late reoperation are significantly higher in patients treated with a PFN compared with patients treated with a PFNA.