Post on 06-Mar-2018
University College Dublin School of Electrical, Electronic and Mechanical Engineering
Effects
Chip Formation
Soft Tissue
Micro Fractures
Thermal
Bone Cells
Variables
Frequency
Amplitude
Force
Cutting tip Design
The Development of Next-Generation Ultrasonic and Vibration Assisted Surgical Tools for Bone Cutting
(VIBONE)Cathal Heavey, Prof. Gerry Byrne, Dr. Eamonn Ahearne
Abstract
Components of an Ultrasonic Bone Cutting System & Challenges
Collaborating Company: Stryker Instruments
Bone cutting is one of the oldest procedures in surgical medicine. However the design of saws and drills has not
advanced significantly in recent decades. Non-conventional processes are being developed to overcome the
shortcomings of today's tools. One such process is ultrasonic/vibration assisted bone cutting. Reported benefits include
reduced reaction forces, and less collateral damage and fiber tearing.
Advanced Manufacturing Science (AMS) Research Centre, Mechanical Engineering, University College Dublin, Belfield, Dublin 4, Ireland
Amplifier andControl System
Conventional Bone Cutting Tools
References:[1] Gleizal, A., J. C. Bera, et al. (2007). "Piezoelectric osteotomy: a new technique for bone surgery-advantages in craniofacial surgery." Childs Nervous System 23(5): 509-513[2] Eggers, G., J. Klein, et al. (2004). "Piezosurgery((R)): an ultrasound device for cutting bone and its use and limitations in maxillofacial surgery." British Journal of Oral & Maxillofacial Surgery 42(5): 451-453[3] Lucas, M., A. Cardoni, et al. (2005). "Temperature effects in ultrasonic cutting of natural materials." Cirp Annals-Manufacturing Technology 54(1): 195-198[4] Cardoni, A., A. MacBeath, et al. (2006). "Methods for reducing cutting temperature in ultrasonic cutting of bone." Ultrasonics 44: E37-E42
Outcomes
Understand the fundamental mechanism of material removal for ultrasonic tools
Design a tool that utilises theoptimum parameters for thecutting of bone
Bone Structure
Horn and VibratingCutting Tip
Ultrasonic Transducer
Shortcomings include;
• Reduced Control• High Cutting Force
• Elevated Temperatures• Soft Tissue Damage due to
snagging
Figure 2. Bone is a composite material. It’s properties are highly variable.
Hard Cortical BoneOsteon
Figure 3. A Current Ultrasonic Cutting Device [1,2]
Figure 1. Examples of conventional bone cutting tools
Figure 4. Thermal Necrosis of Bone[3]
Figure 5. Undesirable
Vibrations[4]
Figure 6. Low Material Removal Rate means Increased Surgical Times
Project Objectives
Spongy Cancellous Bone