[Christmas article: A quantitative analysis of the correlation between the size of the femoral head and shoe size – a help for the busy orthopedic surgeon]

Introduction: Preoperative templating in hip arthroplasty surgery is crucial for accurate implant selection and reducing postoperative complications. This study examines whether there is a correlation between femoral head size and shoe size, with the aim of simplifying the preoperative planning process.

Methods: A total of 14 patients had their shoe size and femoral head size measured. Data were analyzed using linear regression and Pearson's correlation analysis to quantify the relationship between the two variables.

Results: The Pearson correlation coefficient revealed a value of 0.80 (p = 0.0007), and the linear regression model showed that 63% of the variation in shoe size was based on femoral head size.

Conclusion: The study demonstrates a strong and significant correlation between shoe size and femoral head size. This correlation could potentially be used to develop a simple calculation method, where femoral head size = (shoe size - 23.9) / 0.36, which may streamline preoperative planning in orthopedic surgery and reduce workload.

Funding: None.

Trial registration: None.