Fig. 3

a A schematic diagram of the screw pull-out test (not to scale). The humeral head was placed in an aluminum box with a hole that was larger than the screw head. To create orthogonal pulling, screw heads were captured in a custom aluminum jig that was connected to a universal joint, which was in line with the load cell and actuator (not shown). b Locations of screw placement for pull-out testing for locations 1–5. Note: plate and drill tower were utilized for consistent trajectory but removed prior to screw insertion and pull-out testing