Femoral sulcus angle measurements: An anatomical study of magnetic resonance images and dry bones

The sulcus angle of the femoral trochlea is particularly important for evaluating the patellofemoral joint. Our experimental study aimed to assess the osseous femoral sulcus angle radiologically in the right and left knees and osteologically in the right and left femurs in males and females. The osseous sulcus angle of 28 male right, 22 male left, 21 female right and 29 female left knees was measured on magnetic resonance images (MRIs) and by a goniometer; the angle was measured in 40 right and 40 left femurs. In MRIs, the mean sulcus angle in males and in females was 134° ± SD 5.1° and 133.2° ± SD 6.7°, respectively. In the right and left knees it was 133.5° ± SD 5.2° and 134.5° ± SD 6.7° respectively. No statistically significant differences were found between right and left knees in MRIs. In dry bones, the mean sulcus angle in the right and left femurs was 142.2° ± SD 9.7° and 141.2° ± SD 7.9°, respectively, with no significant difference. Statistical comparisons between the mean sulcus angle in MRIs and in dry femurs showed highly significant differences (P< 0.01). Our results suggest that there are no differences in the femoral osseous angle between men and women or between the right and left sides. Differences in the techniques and methods of angle assessments could explain the differences in their values.