Research: Research Articles

Optimizing the Entry Point for Reconstruction Nailing of the Femur

Robles, Abrianna S. MD; Najdawi, Jawad J. MD; Wang, Juntian MD; Rockov, Zachary A. MD; Parikh, Harin B. MD; Little, Milton T.M. MD, FAAOS; Marecek, Geoffrey S. MD, FAAOS

Author Information

From the Department of Orthopaedic Surgery, Cedars-Sinai Medical Center, Los Angeles, CA.

Correspondence to Dr. Robles: [email protected]

Little or an immediate family member serves as a paid consultant to DePuy, a Johnson & Johnson company; Globus Medical; and Restor3D and serves as a board member, owner, officer, or committee member of the Orthopaedic Trauma Association and the Western Orthopaedic Association. Marecek or an immediate family member serves as a paid consultant to BoneSupport AB, DePuy Synthes, Globus Medical, Nuvasive, Orthofix, restor3d, Siemens, Zimmer Biomet. Stock options for restor3d. Board or committee member AO Trauma North America and OTA, serves as a board member, owner, officer, or committee member of AO Trauma North America and the Orthopaedic Trauma Association; and has stock or stock options held in Siemens. None of the following authors or any immediate family member has received anything of value from or has stock or stock options held in a commercial company or institution related directly or indirectly to the subject of this article: Robles, Najdawi, Wang, Rockov, and Parikh.

Journal of the American Academy of Orthopaedic Surgeons 31(18):p e721-e726, September 15, 2023. | DOI: 10.5435/JAAOS-D-22-00778

Abstract

Introduction:

Varus after antegrade medullary nailing of the proximal femur is associated with worse outcomes. Anecdotally, a more medialized “trochiformis” entry is beneficial to avoid varus with valgus-bend (greater trochanteric entry) femoral nails. However, the optimal entry point remains unknown. The purpose of this study was to define the optimal entry point for reconstruction nailing.

Methods:

Using standing alignment radiographs from 51 patients, we templated the ideal entry point for straight and valgus-bend nails from three major manufacturers using TraumaCad software. We measured the distance from the tip of the trochanter to the ideal entry site for each nail. We compared piriformis (PF) with trochanteric (GT) entry for each company and across manufacturers.

Results:

The mean greater trochanter offset from the femoral axis was 15.2 mm. The mean PF entry was 5.9 to 6.7 mm medial to the mean GT entry for each company's nail and was statistically distinct. No differences were observed in GT and PF entry points across manufacturers. Only 2 of 153 ideal GT entry points were lateral to the tip of the trochanter. An increased neck-shaft angle (NSA) and increased GT offset were correlated with a more medial ideal entry point.

Discussion:

The ideal entry point for GT nails is similar across manufacturers and is medial to the tip of the greater trochanter; however, PF and GT entry sites remain distinct. During preoperative planning and when executing femoral nailing intraoperatively, it may also be important to consider the NSA and GT offset of a patient before committing to a certain entry point.