Diplomarbeit / Masterarbeit (DA/MA): Kinematic Registration Method for Image-Free Navigated Total Knee Arthroplasty

Advisor: Nassir Navab
Supervision by: Martin Bauer

Abstract

Image-free orthopedic navigation software relies in general on a bone model that is intraoperative generated by identifying certain important landmarks on the actual bone and matching these landmarks to a model.

In this thesis, a new registration method for a certain class of deformities will be developed that is based on the passive movement of the knee joint. The surgeon intraoperative defines the desired postoperative motion by moving the joint under certain pressure. From the kinematic data that is gathered using an intraoperative navigation system, the proposed software extracts the best position and size of the different components of the joint replacement and defines the necessary resection planes. The resections are then performed using the navigation system according to the plan. The proposed method involves extracting a desired virtual motion characteristic from the kinematic movement and matching these characteristics to the available implant surfaces using nonlinear optimization with certain constraints imposed by the implant and surgical technique. This leads to a kinematically optimized implant placement, which is expected to improve implant durability and function.

Task

The work is based on an existing conceptual idea for the proposed registration method. Goal of this work is to define and validate the appropriate algorithms and workflows to be used to accomplish reliable and useful results, in particular with respect to operational safety for a later commercialization. The algorithms will be tested with a prototypical software implementation using saw bone and cadaver studies.

Requirements

• some programming skills, preferably MATLAB
  
• some 3D graphics knowledge
  
• good understanding of 3D geometry and optimization algorithms, potentially some knowledge in rigid registration
  
• motivation to do research
  
• team player, willingness to spend at least 1 or 2 days per week with us in our Feldkirchen office
  

What you get out of it

• nice working environment in a small team
  
• close contact to the CAS industry
  
• hands-on training and direct support
  
• reimbursement for transportation costs to our office and other expenses
  

Contact

Contact at the chair: Tassilo Klein

Contact at DePuy:

Dr. Martin A. Bauer
CAS Application Engineer
DePuy iOrthopaedics
a Business Unit of DePuy Orthopädie GmbH
Kapellenstr. 10
D-85622 Feldkirchen

Phone: +49 89 205074-304
E-mail: