Side-to-side variation in normal femoral morphology: 3D CT analysis of 122 femurs - 13/02/16

Doi : 10.1016/j.otsr.2015.11.004

D. Dimitriou ^a, T.-Y. Tsai ^a, B. Yue ^b, H.E. Rubash ^a, Y.-M. Kwon ^a, G. Li ^a,^⁎
^a Bioengineering laboratory, department of orthopaedic surgery, Massachusetts general hospital/Harvard medical school of Boston, 55, Fruit Street, GRJ 1215, Boston, Massachusetts MA 02114, USA
^b Department of orthopedics, Ninth People's hospital, Shanghai Jiaotong university school of medicine, Shanghai, China

^⁎Corresponding author.

conectar o crear una cuenta

Bienvenido a EM-consulte, la referencia de los profesionales de la salud.
Artículo gratuito.

Conéctese para beneficiarse!

Abstract

Background

The contralateral femur is often used as reference for reconstruction in unilateral hip joint pathology. The objective of this study was to quantify the side-to-side variation in proximal femur. We hypothesized that significant side-to-side differences exist between left and right femur with implications for preoperative planning and leg length discrepancy following hip arthroplasty.

Materials and methods

CT-based 3D femoral models were reconstructed for 122 paired femurs in 61 young healthy subjects (46.9±6.8 years) with no history of hip pathology. Side-to-side differences of several femoral morphologic parameters, including femoral head diameter, femoral anteversion, horizontal offset and femoral head center location, were compared and correlated with demographic factors using multiple linear regression.

Results

Significant side-to-side differences (P<0.01) were found in femoral anteversion (4.3±3.8°; range: 0.2° to 17.3°), horizontal offset (2.5±2.1mm; range: 0.1 to 10.3mm), and femoral head center location (7.1±3.8mm; range: 0.5 to 19.4mm). The difference in femoral anteversion was strongly correlated with the difference in neck diameter (R²=0.79), whereas the difference in horizontal femoral offset was highly correlated with the head diameter difference (R²=0.72). Femoral head center difference was correlated with the femoral anteversion, horizontal offset and neck-shaft-angle difference (R²=0.82).

Discussion

Relying on the anatomic landmarks of the contralateral femur during hip arthroplasty may not necessarily result in restoration of native anatomy and leg-length. Knowledge of the baseline side-to-side asymmetry could provide a range of error that would be tolerable following hip reconstruction.