Radiological evaluation of the relationship between femoral head rotation center and trochanter major

Abstract

Purpose: We aimed to investigate the distance between the tip of Trochanter Major (TTM) and the Femoral Head Rotation Center (FHC) and investigate other measurements on orthoroentgenograms obtained in the local population. Materials and methods: Patients aged 18 and over who were admitted to the hospital between 2 June 2020 and December 2020 and had an orthoroentgenogram were included in the study. Patients with hip joint degeneration, deformities, bone dysplasia, bone tumors, bone tissue irregularities, old fractures or surgical findings, and those with lower extremity length discrepancies were excluded from the study. The tip of trochanter major - The femoral head rotation center (TMFH) distance, collodiaphyseal angle, femur length, and femoral head area were measured on the orthoroentgenogram. Radiological measurements were made by two orthopedic specialists who participated in the study. In addition, the age and gender of the patients and the side of the femur evaluated were recorded. Results: When evaluated according to gender, it was observed that the femoral length of the males was approximately 35.37 ± 5.6+3 mm longer than that of the females, and the femoral head area was 3 ± 1.4 cm2 larger compared to the females (Table 1). These differences between the genders were considered statistically significant (<0.001). The mean collodiaphyseal (CD) angle of 180 femurs included in the study was 131.9o ± 5.2o,the TMFH distance was measured as 4.77 ± 5.0 mm, the tip of trochanter major was above the femoral head rotation center. There was no statistically significant difference in this distance in terms of gender and mean right/left side measurements. Conclusions: The relationship between the femoral head rotation center (FHC) and the tip of the trochanter major (TTM) is a viable method in determining the lower extremity length. While evaluating this relationship, the values of the nonaffected contralateral hip can be used. However, if any deformity in the contralateral hip occurs, measurements obtained in the local population could be helpful in providing information about appropriate leg length. Keywords: Hip reconstruction, anthropometry, proximal femoral anatomy, femoral head rotation center, trochanter major ________________________________________________________________