An increasing number of patients suffer from hip joint degeneration. One possible treatment is hip replacement surgery, during which natural components of the ball-and-socket joint are substituted by artificial ones. In detail, the ball-shaped head of the femoral bone is removed and replaced by an implant that is inserted into the thigh bone. However, the implant can be too strong, causing a reduction in the stresses that act on the remaining natural bone, i.e., stress shielding. Stress shielding can result in bone resorption, which, in turn, can cause implant loosening. To counteract stress shielding, implant designs that are inspired by porous bone are proposed [1]. In particular, the designs comprise lattice structures, which can additionally facilitate bone in-growth and can be produced by additive manufacturing. Such implants comprising lattice structures can be numerical analyzed to predict their performances and eventually even enable their numerical design. The required geometric models of such implants can be generated by composing splines, following the approach of tiling [2]. The generated models are not only suitable for a direct isogeometric analysis, but the approach also enables local optimization of the lattice structures [3]. The presentation will apply the workflow to an exemplary scanned bone geometry. [1] P. Müller, A. Synek, T. Stauß, C. Steinnagel, T. Ehlers, P.C. Gembarski, D. Pahr, R. Lachmayer, Development of a density-based topology optimization of homogenized lattice structures for individualized hip endoprostheses and validation using micro-FE. Scientific Reports (2024) 14:5719. [2] G. Elber, Precise construction of micro-structures and porous geometry via functional composition. Mathematical Methods for Curves and Surfaces (2017) 108–125. [3] J. Zwar, G. Elber and S. Elgeti, Shape optimization for temperature regulation in extrusion dies using microstructures. Journal of Mechanical Design (2023) 145(1):012004.