Engineered Components Steering system Steering system Plate Plate End cap End cap Positioning rings Positioning rings Stabilizers Stabilizers String Placement String Placement Suction and lubrication systems Suction and lubrication systems Drill Stand Drill Stand

Problem Definition Drill a curved hole through the spine Drill a curved hole through the spine Used for medical procedures Used for medical procedures i.e. spinal surgery, hip replacement, bone screws i.e. spinal surgery, hip replacement, bone screws Improved patient recovery time Improved patient recovery time Less invasive anterior and posterior approaches Less invasive anterior and posterior approaches Increased mobility Increased mobility Objectives Objectives Angle of approach equal to 45° Angle of approach equal to 45° Hole diameter of 5.5 – 7 millimeters Hole diameter of 5.5 – 7 millimeters

Definition of Scoliosis Condition that involves complex lateral and rotational curvature of the spine Condition that involves complex lateral and rotational curvature of the spine Congenital – anomalies present at birth Congenital – anomalies present at birth Idiopathic – occurs during lifetime Idiopathic – occurs during lifetime Developed from other symptoms Developed from other symptoms

Current Scoliosis Treatments Bracing is recommended when initial curve magnitude is between 20% and 40% Bracing is recommended when initial curve magnitude is between 20% and 40% Reduction of curvature between 25 and Reduction of curvature between 25 and 35 degrees Negative side effects of discomfort and psychological anguish Negative side effects of discomfort and psychological anguish Surgical procedure involving screws and inserting metal rods to straighten the spine Surgical procedure involving screws and inserting metal rods to straighten the spine Time consuming with a six month recovery time Time consuming with a six month recovery time

Budget ItemProposed ($)Spent ($)Difference ($) Rotary Drill Bit Flexible Shaft Casing Power System Experiment Budget Total

Technical Approach Procedures Procedures Three phases performed concurrently Three phases performed concurrently Design phase – design components Design phase – design components Build phase – assemble drill and model spine Build phase – assemble drill and model spine Test phase – drill curved hole in spine Test phase – drill curved hole in spine Milestones Milestones Progress Report, Student Expo Presentation, Poster Presentation, Final Report, Delivery of Prototype Progress Report, Student Expo Presentation, Poster Presentation, Final Report, Delivery of Prototype

Gantt Chart

Prototype Components Suction and Lubrication System Suction and Lubrication System

Current Drill Prototype Plate steering system Plate steering system Three strings Three strings Angle of strings to shaft: 15°, 30°, 45°, 60° Angle of strings to shaft: 15°, 30°, 45°, 60° Cutting Head Cutting Head Carbide burr Carbide burr

Drill Stand Concept drawing Concept drawing Designed to hold drill during surgical procedure Designed to hold drill during surgical procedure To minimize number of hands needed to complete procedure To minimize number of hands needed to complete procedure Placed on operating room tray Placed on operating room tray

3-Phase Drilling Phase 1 Phase 1 Insertion into Insertion intovertebrae Phase 2 Phase 2 Navigating Navigating the bend the bend Phase 3 Phase 3 Directed Directeddrilling

Material Testing Drilled curved hole Drilled curved hole Point- and Push-the-Bit Point- and Push-the-Bit Compound curve Compound curve Model Spine Model Spine 2:1 scale 2:1 scale Represents layers Represents layers of bone

Deflection Testing Deflection Angle (°)Ave Mass (kg)Weight (N)Trial 1Trial 2Trial 3Angle (°) HorizontalPosition (mm)VerticalPosition (mm) Mass (kg) x- coordinate y- coordinateMass (kg) x- coordinate y- coordinate

Deflection Results

Progress Challenges Unexpected Technical Challenges Unexpected Technical Challenges Drilling through plaster Drilling through plaster Completing surgical procedure in one phase Completing surgical procedure in one phase Keeping drill level Keeping drill level Keeping tension in the strings Keeping tension in the strings Modeling drill tip using mathematical equations Modeling drill tip using mathematical equations

Deliverables Written technical progress report Written technical progress report Delivered [12/12/06] Delivered [12/12/06] Final drill prototype Final drill prototype [5/7/07] [5/7/07] Test model with drilled holes Test model with drilled holes [5/7/07] [5/7/07] List of further recommendations List of further recommendations [5/7/07] [5/7/07] Drawings and prints for future assembly (CD format) Drawings and prints for future assembly (CD format) [5/7/07] [5/7/07] Written final report Written final report [5/7/07] [5/7/07]