During spinal fusion surgery multiple vertebrae are fused by fixating them together with an internal brace. The brace is connected to a vertebra with pedicle screws. The inside of the bone (cancellous bone) is too weak to achieve sufficient grip. Therefore, screw fixation mainly relies on locations where the screw is in direct contact with the surrounding  layer of the much harder cortical bone. We are developing a steerable bone drill in order to increase the contact area of screws and cortical bone by drilling along the cortical bone layer. An optical sensing system that can differentiate the two types of bone tissue will help the surgeon find and maintain the right drilling trajectory. Furthermore, a novel anchoring device that is flexible during insertion, but becomes rigid once in place will replace straight pedicle screws.

There are multiple graduation projects available related to optical sensing, bone drilling and anchoring.

• Development of a bone phantom for testing of a steerable drill or screw
  Contact: Merle Losch, m.s.losch@tudelft.nl
  
• Design of a drill prototype to provide directional feedback
  Contact: Merle Losch, m.s.losch@tudelft.nl

• Design of  flexible screw that can become incredibly stiff in order to transfer the forces acting of the screw
  Contact: Esther de Kater, e.p.dekater@tudelft.nl
  
  
• Design of a flexible screw that adheres to the bone surface in order to transfer the forces acting on the screw
  Contact: Esther de Kater, e.p.dekater@tudelft.nl