DOI

10.17077/etd.52t7-4ngm

Document Type

Dissertation

Date of Degree

Summer 2017

Access Restrictions

Access restricted until 09/04/2020

Degree Name

PhD (Doctor of Philosophy)

Degree In

Biomedical Engineering

First Advisor

Anderson, Donald D.

First Committee Member

Thomas, Geb W.

Second Committee Member

Reinhardt, Joseph M.

Third Committee Member

Grosland, Nicole M.

Fourth Committee Member

Marsh, J. Lawrence

Abstract

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 intra-operatively may facilitate improved long-term outcomes. Further development and study of this system is warranted.

Keywords

Biomechanical Guidance, Contact Stress, Fracture Reduction, Intra-articular Fracture, Orthopaedics, Surgical Visualization

Pages

xiv, 131 pages

Bibliography

Includes bibliographical references (pages 117-126).

Copyright

Copyright © 2017 Andrew Martin Kern

Available for download on Friday, September 04, 2020

Share

COinS