Use of Inherent Anteversion of an Intramedullary Nail to Avoid Malrotation in Comminuted Femur Fractures: A Prospective Case- Control Study.

OBJECTIVES: To (1) evaluate using the inherent anteversion of a second or third generation femoral nail to set the version of the femur during locked intramedullary nailing of comminuted femoral shaft fractures (Espinosa Technique [ET]) and compare it with our traditional method (traditional group [TG]) and (2) assess the variation of anteversion because of the inherent play in the nail itself.

DESIGN: A prospective IRB-approved study.

SETTING: Academic US Level 1 Trauma Center.

PATIENTS: Fifty-two consecutive patients with comminuted femur fractures all completed the study.

INTERVENTION: The first 27 patients had the anteversion determined using the patellar shadow and lesser trochanter (TG), and the next 25 patients were treated by ET.

MAIN OUTCOME MEASURE: Computed tomography scanogram for femoral anteversion and length in the normal versus operated femur.

RESULTS: A >15 degree difference from native to operated legs was found in 8/27 TG (29%, 95% CI 15.3%-54.2%), with a mean difference of 11.6 ± 10.2 degrees (95% CI 8.8-16.17) verses 1/25 in the ET group (2.5%, 95% CI 0%-15.3%), with a mean difference of 4.8 ± 6.2 degrees (95% CI 1.38-8.9) (P = 0.0068). There was a 5 degree variability in our ability to center the proximal locking screw in the femoral head and 5 degrees variation in distal locking.

CONCLUSIONS: The inherent anteversion of a second generation nail can be used to minimize malrotation of the femur after comminuted fractures during locked intramedullary nailing in patients with normal anteversion and is superior to our present fluoroscopic technique.

LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.