RESUMO
The currently used intralesional or marginal surgical treatment of a bone tumour in the extremities shows some shortcomings in providing a restoration of the mechanical strength of the bone and the containment of the used filling materials. The use of a medical image based, preformed and custom-made titanium membrane screwed onto the periosteal side of the bone is introduced. This study looks in detail into the design process and the biomechanical evaluation of such a membrane. The buckling strength of the membrane, the strength at the perforation holes and the strength of the screw-bone fixation are tested experimentally. The two latter experiments are performed with different screw types. From the performed tests it appears that a titanium membrane without a wave pattern, of 0.3 mm thickness, fixed to the bone with seven trabecular bone screws (4 mm diameter and 28 mm length) is capable of carrying the anticipated mechanical loads on the reconstructed tibia. The medical image based design methodology and the first clinical application of such a preformed and custom-made titanium membrane are reported and discussed. The feasibility of preformed titanium membranes for bone reconstruction in tumour surgery is demonstrated.
