Measuring stem anteversion after total hip arthroplasty: posterior condylar tangent versus transepicondylar axis.

TEA and PC demonstrated to achieve a good correlation, not dependent from the condyle morphology. However, the difference between the two measurements (5°) can severely influence the combined anteversion (10-20%): due to clinical applicability and better inter/intra-observer agreement, TEA should be preferred for measuring stem anteversion.