Background Bone mechanical properties, including strength and stiffness, influence intraoperative fracture risk and implant stability in hip arthroplasty. Surgeons frequently utilize radiographic metrics to evaluate bone quality and inform surgical strategies. This study investigates the correlation between radiographic bone metrics and the mechanical properties of the femoral neck. Methods Femoral neck cortical bone samples from 23 patients undergoing elective hip arthroplasty were subjected to mechanical compression testing to measure elastic modulus and ultimate strength. Density was also measured. Radiographic metrics, including cortical thickness index, canal flare index, canal–bone ratio and canal–calcar ratio, were determined from preoperative radiographs. The correlations between these metrics and bone mechanical properties were analysed using linear regression, with intra‐ and interobserver reliability assessed. Results Analysis included 19 of the 23 participants. Whilst cortical thickness index measurements demonstrated a weak positive correlation with bone density ( R 2 = 0.291; p = 0.013) and ultimate strength ( R 2 = 0.279; p = 0.015), canal–bone ratio showed a weak negative correlation with both factors ( R 2 = 0.291; p = 0.013 and R 2 = 0.279; p = 0.015, respectively). Both cortical thickness index and canal–bone ratio demonstrated excellent inter‐ and intraobserver reliability. Neither canal flare index nor canal–calcar ratio correlated with any mechanical properties, and none of the radiographic metrics correlated with elastic modulus. Conclusions Cortical thickness index and canal–bone ratio correlate weakly with bone strength and density but not with elastic modulus. Given their limited utility, radiographs should be used with caution in surgical decision‐making regarding impaction force and implant fixation strategy.
Karia et al. (Thu,) studied this question.