The relationship between the femoral artery and vastus medialis muscle coverage at the adductor hiatus during medial closed wedge distal femoral osteotomy in valgus knees.

ABSTRACT

Purpose: The purpose of this study was to examine the location where the femoral artery contacts the vastus medialis at the adductor tendon hiatus, which is important when using the subvastus approach in medial closed wedge distal femoral osteotomy. We evaluated the correlation between differences in height, vastus medialis morphology, and lower limb alignment. Methods: Sixty knees (16 male, 44 female) that underwent plain computer tomography (CT) were included. Using the radiographic hip-knee-ankle (HKA) angle as a reference, the knees were divided into three groups of 20 knees valgus, varus, and neutral. The mechanical lateral distal femoral angle (mLDFA) and distance from the medial femoral epicondyle to the centre of the femoral head (D1) were measured on full-length weight-bearing anteroposterior radiographs. The first cross-section on CT where the vastus medialis muscle and femoral artery connect was defined as the cross-sectional image for measurement. The direct distance from the medial epicondyle to the measured cross-sectional image (D2) was measured in the coronal view. The ratio of the vastus medialis muscle width to the femoral posterior wall width was defined as the vastus medialis muscle coverage ratio (CR). Correlations between each measurement and group were evaluated. Results: There was a positive correlation between D1 and D2 in the overall, neutral, and varus groups; however, there was no correlation in the valgus group. A positive correlation was observed in terms of the relationship between CR and D2 in the overall and valgus groups. In addition, there was no statistically significant difference in the correlation between the mLDFA and D2, with patient height as a control variable overall and in all groups. Conclusion: In the valgus group, distance to the adductor hiatus was correlated with vastus medialis coverage. Overhang of the vastus medialis may be an important influencing factor of femoral and popliteus artery position. Level of Evidence Level III, retrospective cohort study.