Modular Retractor for Hip Replacement SurgeryDepartment of Biomedical Engineering, Department of Electrical Engineering, Department of Mechanical Engineering, Vanderbilt University

Sponsor: Dave Martinez, Dr. Michael Christie

Hassan Atassi (BME), Azni Nabela Wahid (ME), Mohamed Osman (BME), Noor Naziha Mohd Lazim (BME/EE), Mohammad Zulfadhli Zolkaffly (EE)

Problem Statement

Background

Purpose

Modular Retractor

Device Design

Safety & Costs

Acknowledgement

Design a Modular Retractor to remove inefficiencies in the current retractor instrument in order to decrease the number of instruments needed in in hip replacement surgery as well as to make hip surgery more efficient and safer.

HIP REPLACEMENT SURGERYEvery year approximately 300,000 hip replacement surgeries occur in the United States. This number is expected to grow to 600,000 by 2015.

SURGICAL RETRACTOR• Used to Actively separates the edges of a surgical incision or

wound to create a larger working area for the surgeon and limit incision size.

• Available in variety of sizes and shapes: Choice depends surgeons training/ patient

PROBLEMS• Multiple versions of the same retractor needed to do the same

job because of varying patient size.

• Limited Size Permutations: never exact fit to patient size.• Decreased surgeon field of view (too large)• Ineffective & causes injury (too small)

• Adipose tissue wraps around retractor making it inefficient.

• Handle is uncomfortable to grasp during long surgery.• Average user changes hand position every 71 seconds

Create a proof of concept modular retractor (Hibbs) that incorporates:• Alterable handle length & blade depth• Interchangeable handle types and tips• Ergonomic handle• Adipose tissue accessory

Safety Concerns• Protruding plunger could damage tissue • Small potential for components to unintentionally dislodge

CostLabor: Prototype = $860 (Quick Parts)Plunger= $29.76 (JW Winco)Total Cost: 11,689.76

We would like to thank Dave Martinez, Dr. Michael Christie, Dr. Paul King, Dr. Joel Barnett, & St. Thomas Hospital for their support in the completion of this project.

Plunger Locking Mechanism (JW Winco) Adipose Accessory Attachment Mechanism

Detachable Adipose Accessory TOP: Longest , BOTTOM: Shortest

STANDARD HIBBSModel Handle Length Blade Depth Blade Width

Standard 8” 3” 1.5”

Medium 9.75” 4.5” 1.5”

Extra Large 13” 6.5” 1.5”

MODULAR RETRACTORHandle Length Blade Depth Blade Width

7.68” 4.67” 1.53”

8.49” 5.26”

9.3” 5.85”

10.11” 6.44”

10.92”

11.73”