External fixation design evolution enhances biomechanical frame performance.

Background: External fixation has become a quick and easy application for fracture stabilisation of the extremities and/or pelvis to maintain the reduction and provide stability while sparing the soft tissues. Over the last years, enhanced construct stiffness has become an essential requirement to preserve fracture reduction, particularly in active and overweight patients. This study was performed to determine whether the advancement of design features enhances the external fixation construct stiffness.

Effect of callus development on the deformation of external fixation frames.

Purpose: We designed a sensor that measures the bending moments at the articulations and the torque of the rod of a Hoffmann II® external fixation. We considered the effect of the callus formation in the stabilisation of a "fracture-fixation system."

Methods: Four Hoffmann II® frame configurations were mechanically tested.