Bone morphology of the proximal femoral canal: ethnicity related differences and the influence on cementless tapered wedge stem designs.

Background: Differences in proximal femoral morphology between ethnicities may have implications on the design of cementless tapered wedge stems. This study analyses the differences in Asian and Caucasian bone morphology as well as the related fit of various cementless tapered wedge stem designs.

Methods: A computed tomography database and modelling software was used to retrospectively analyse a total of 1345 femora. Ethnicity related comparisons as well as the fit of the stem designs were analysed.

Results: Statistically significant differences between canal shape of Caucasian and Japanese as well as non-Japanese Asians were observed. The fit of the stems within the femoral canal was highly dependent on the respective stem shape.

Conclusions: The shape differences in stem designs had a larger influence on the fit within the femoral canal than the differences in ethnicity related to bone morphology.