In situ imaging of a bone-biomaterial-composite to understand mechanical interactions

Important results from the project

With age and disease, the bone´s strength and toughness decrease. Injectable biomaterials or bone cement can be used to strengthen the bone´s strength so that e.g. enable support for screws and implants. It is important to understand how the bone and bone-biomaterial composite behaves under load in order for this technique to reach clinical application. The project aimed to determine how a biomaterial injection can affect bone strength and bone damage mechanisms at the microscale in trabecular bone. The project was in collaboration between Bone Support AB and Lund University (LU).

Expected long term effects

The results show how the bone-biomaterial composite works under load, and how much the biomaterial strengthens the bone. It shows that the fracture pattern differs substantially in the bone-biomaterial composite compared to bone alone, where cracks mainly occur in the biomaterial first, which protects the bone to some extent. The results can motivate clinical translation, as well as being used as an indication of further biomaterial development.

Approach and implementation

The project used experimental in situ mechanical loading at the same time as high-resolution tomographic imaging inside a beamline at a synchrotron facility (TOMCAT, PSI, Switzerland). The experiment was combined with another beamtime of the researchers at LU. Several image datasets were collected under increasing load until fractures occurred. This enabled image correlation between the datasets and calculation of strain fields in the bone before and during cracks. Crack initiation and crack growth were monitored and analyzed relative to the mechanical properties.