Intra-articular fractures (IAFs) often lead to poor outcomes, despite surgeons’ best efforts at reconstructing the fractured articular surface. The objective of articular fracture reduction is to improve joint congruity thereby lower articular contact pressure and minimize the risk of post-traumatic osteoarthritis (PTOA). Surgical fracture reductions performed using less invasive approaches (i.e., percutaneously) rely heavily upon C-arm fluoroscopy to judge articular surface congruity. Based on varied outcomes, it appears that the use of 2D imaging alone for this purpose may prove inadequate. Despite this, there has been little investigation into novel metrics for assessment of reduction quality.

This work first explores seven methods for assessment of reduction quality (3 2D, 3 3D, and one biomechanical). The results indicate that metrics which take 3D measurement or joint biomechanics into account when characterizing reduction quality are more strongly correlated with PTOA development.

A computer assisted surgery system, which provides up-to-date 3D fracture geometry and contact stress distributions intra-operatively, was developed. Its utility was explored in a series of ten cadaveric tibial plafond fracture reductions, where contact stresses and contact areas were compared in surgeries with vs. without biomechanical guidance.

The use of biomechanical guidance caused an increase in surgical time and fluoroscopy usage (39% and 17%, respectively). However, it facilitated decreases in the mean and maximum contact stress by 0.7 and 1.5 MPa, respectively. Contact areas engaged at known deleterious levels (contact stress > 4.5 MPa) were also 44% lower in cases which used guidance.

The findings of this work suggest that enhanced visualization of a fracture intraoperatively may facilitate improved long-term outcomes. Further development and study of this system is warranted.