TUHH BoneStress is an interactive model demonstrating the effects of impaction and joint loading on bone stresses for different hip stem designs. It describes radial load transfer between implant and bone in uncemented press-fit femoral stem implantations.

This app provides a visual representation of the stress states between press-fit implant and bone directly post-operatively, and after bone ingrowth.

Stem design (stem and neck lengths, neck angle), impaction force, and joint loading can be varied to limit implant-bone separation while maintaining bone stresses within “normal” or “osteoporotic” limits. This will allow bone ingrowth and reduce stresses, which can be displayed.

Its intuitive use makes TUHH BoneStress the perfect learning tool for surgeons and their patients by demonstrating the influence of stem design, implantation conditions, and patient activity, on the local stress situation, and its effect on successfull bone ingrowth.

It is noted that the simple model used cannot be directly transferred to an individual patient situation.