Antegrade versus retrograde nailing of proximal femur fractures: A cortical diameter based study.

Background: Retrograde nailing of proximal femoral shaft fractures is controversial. The purpose of this study was to compare patients with proximal femur fractures undergoing antegrade versus retrograde intramedullary nailing (AIMN vs RIMN) and determine the safety and efficacy of RIMN.

Methods: A retrospective review was performed on 54 patients undergoing femoral IMN for proximal femoral shaft fractures at an urban level one trauma institution between January 2016 and July 2021.Fracture distance from the lesser trochanter (LT) was recorded and used to calculate the number of cortical diameters (NCD) from the LT. Proximal femur fractures were defined as < 3 NCD. AIMN and RIMN fixation was utilized in 31 (57.4%) and 23 (42.6%) patients, respectively. Outcomes measures included pre-/postoperative true translational and angular displacement (TTD and TAD), operative time, estimated blood loss (EBL), union rate, time to union, complications, and reoperations.

Results: AIMN and RIMN groups were similar in terms of age, sex, BMI, tobacco use, diabetes, ASA classification >2, AO/OTA classification, preoperative TTD or TAD, open fractures, or ballistic fractures. The AIMN group, had a shorter measured distance from the LT (47.0 vs. 66.1 mm, p = 0.04) but the difference in NCD was not significant (1.4 vs. 2.0, p = 0.07). Among patients with isolated IMN procedures, the RIMN group had shorter operative times (142.3 vs. 178.5 min, p = 0.01) and less EBL (100 vs. 250 mL, p = 0.008). There was no observed intergroup difference in terms of postoperative TTD/TAD, union rate, time to union, complications, or reoperations.

Conclusion: RIMN is a viable treatment option for proximal femoral shaft fractures that results in less operative time, less blood loss, and no detectable differences in union, reoperations, or complications.

Level Of Evidence: Level III, Retrospective cohort study.