An Excel-Based Tool for Simplified Three-Dimensional Measurement of Femoral Neck Anteversion

Objective: We devised a simple three-dimensional (3D) application for femoral neck anteversion (AV) measurement using cross-sectional computed tomography (CT). To assess the accuracy and reproducibility of this method, we compared it with two previously established cross-sectional CT methods.

Materials and methods: AV measurements using CT were performed on 11 consecutive patients before primary total hip replacement for osteoarthritis. The mean age was 72 years (range, 53-81 years); all patients were females. Inter- and intraobserver variabilities were assessed. The measurement times of each method were compared. The correlations with the results obtained using 3D modeling software were also assessed.

Results: Interobserver reliability measured as the intraclass correlation coefficient (ICC) was 0.89, 0.84, and 0.76 for the method of Reikeras et al., the single-slice method, and our method, respectively. The intraobserver reproducibility of all the methods was excellent (range, 0.86-0.97). AV measurements using the 3D modeling software positively correlated with the single slice method (r=0.70) and the method of Reikeras et al. (r=0.60). Notably, the positive correlations with our method were excellent (r=0.93). Measurement time of this method was significantly longer than the other methods.

Conclusion: This simplified method achieves a good level of accuracy and reproducibility. This method can be used in clinics with no access to 3D measurements.