Comparison of Cross-Table and Lauenstein Lateral Views for Tip Apex Distance Measurement in Trochanteric Fracture Fixation

BackgroundTip apex distance (TAD) is a commonly used radiographic index to evaluate the risk of mechanical failure following internal fixation of trochanteric femoral fractures. While the cross-table lateral view (C view) is typically used to assess TAD, Lauensteins I view (L view), which approximates the true lateral view, may also allow for reliable measurement. However, the consistency of TAD measurements across different lateral projections has not been fully investigated. MethodsWe conducted a retrospective cohort study of patients who underwent internal fixation with a short femoral nail for trochanteric fractures between July 2016 and January 2020. Patients who had both C view and L view radiographs postoperatively were included. TAD was measured on each view and compared using paired t-tests. Pearsons correlation coefficient was calculated, and agreement was evaluated using Bland-Altman analysis. ResultsA total of 31 patients were included. The mean TAD was 8.55 mm (SD, 2.40; 95% CI, 7.62-9.48) in the C view and 9.63 mm (SD, 3.34; 95% CI, 8.41-10.84) in the L view, with a statistically significant mean difference of 1.06 mm (p = 0.027; 95% CI, 0.13-2.03). A moderate positive correlation was observed between the two views (r = 0.637, p < 0.001). Bland-Altman analysis showed good agreement between the two measurements. ConclusionsAlthough a statistically significant difference in TAD measurements was observed between C view and L view, the correlation and agreement were relatively high. These findings suggest that L view may serve as a practical alternative when obtaining the C view is not feasible. Further studies are warranted to confirm these results and evaluate their clinical implications.