Adaptable Retractor for Total Hip Replacement Surgery

1. Trey DeLong Lacey Gorochow Brian Rappa Adam Vandergriff Sandra Wadeer Advisor: Dave Martinez VP of Sales at Zimmer, Inc. Adaptable Retractor for Total Hip Replacement Surgery

2. Problem Statement • Current tissue retractors are narrow, multiple retractors are required especially in obese patients • NY times reports 34% adults are obese • +Surgical Techs($20.00/hr*2-4hr/surgery*200k surgeries/year) • Time of surgery increases as well • Previous team designed an adjustable retractor • Complex and impractical for industrial production • Prototype could not be used in surgery

3. Mechanism & Consequences • Mechanism causing the problem Physical properties of adipose tissue allow it to wrap around narrow retractors • Consequences of unresolved problem Poor surgical field of vision Increase cost for additional materials and personnel

4. Conflict Map

5. Adaptor Design Requirements • Must fit multiple patient sizes and provide a clear view of the surgical site • Must be cost efficient • Must function adequately in the surgical procedure • Be able to be sterilized • Strong enough to hold back fat tissue

6. Ideal Device • Easy to use • Small size • Simple design- easy to manufacture • Lightweight • Biocompatible

7. Primary Objectives Design a modular adaptor for retractors that: • Keeps back adipose tissue • Is easily used by surgeon • Attachment technique • Is simple to manufacture • Use cheap material & • Production method • Is ready for use in surgery • Easily sterilized • One time use

8. Preliminary Design 1 • Wing-like structure • ≈ 5 inches • 10 inch single incision • Attachment mechanism: • Hook and slot • Tapering method • 1-1.5 in. wide • Form by bending metal • Non-disposable • Stainless steel

9. Design 2 • Disposable • Plastic material • Attaches to retractor • Multiple sizes • Requires holding

10. Design 3 • Similar to cheek retractor • Plastic material • Disposable • Hands-free

11. Goals • Reduce total hip replacement surgery cost • Less personnel in the operating room • Less retractors needed for surgery • Increase vision and work room for the surgeon • Increase efficiency of the surgery • Reduce surgery time

12. Performance Metrics • Retractor system work on 95% of patients • Different size attachments for non-disposable and disposable design • Costs • Keep production costs minimal • Mass production • Readily machined • Predicted to be ~$300 for retractor and attachments (non-disposable) • Disposable: $1-$10 per device

13. System and Environment • Role in surgery • Increase view of region and allows access • Why its beneficial to the surgeon • Reduce people near patient • Reduce number of retractors • Make surgery easier

14. Testing Methods • Verification • Validation • Hardware Testing • Stress Testing • Pro/E Mechanical Analysis • Safety Testing

15. Next Steps…

16. References • http://www.bls.gov/bls/blswage.htm • http://www.innomed.net/hip_rets_mis.htm#Anchor-APC-49575 • http://www.nytimes.com/2010/01/14/health/14obese.html • http://www.orthosupersite.com/view.aspx?rid=1889 • http://www.zimmer.com/z/ctl/op/global/action/1/id/8140/template/PC/navid/10427