Total Disc Replacement

1. Total Disc Replacement - UjwalParikh

2. Scope Scope of the totaldisc replacement is to create a disc model that would improve the longevity and functionality of the implant to reduce pain.

3. Anatomy Human spine – 24 articulating vertebrae, 9 fused vertebrae. Stacked to form vertebral column maintaining human body’s upright posture. Each segment consists of vertebrae and spinal disc. Spinal Disc: Nucleus pulpous (Jelly) Annulus fibrosis (Stronger)

4. Anatomy

5. What is TDR? TotalDisc Replacement (TDR) is surgical procedure replacing vertebral disc by an implant. Surgeon removes the worn-out, painful, degenerated disc replaces by metal implant. The goal is to reduce pain still maintaining complete functionality of spine. First clinical trial performed by Fernstorm in 1966 on 125 patients, 88% reduction. CHARITÉ Artificial Disc (De Puy Spine, Inc.)

6. Why TDR? Degeneration of intervertebral disc in lower spine may lead to chronic back pain. The chronic nature results in reduced functionality hindering patient’s everyday life. Approximately 80% of Americans experience a significant back pain in their life time. Treatments Anti-Inflammatory Medication Surgical I Spine fusion (Traditional) II Artificial Disc Replacement

7. Spinal Fusion Vs. TDR

8. Design Input PRODISC® (Spine Solutions, New York, NY, USA) CHARITÉ Artificial Disc (De Puy Spine, Inc.) L4-L5 vertebrae

9. Steps followed…. Plate Assembly Polymer Mechanical

10. Plate

11. Plate (Contd…) Anterior View Isometric View Lateral View Superior View

12. Plate (Contd…)

13. Assembly

14. Polymer

15. Assembly + Polymer Lateral View Anterior View Isometric View

16. Material

17. Analysis

18. Analysis (Contd…)

19. Conclusion Since max. stress on polymer < tensile strength of Urethane L42, polymer won’t rupture Also max. stress on plate < yield strength of Ti6Al4V, metal wont break either for the given force and degree of freedom. For a force of 43.33 N, Angular displacement= 10 deg. Stiffness = Moment/Angular Displacement = 1.72 Nm/deg

20. References http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MTP641 http://www.dsm.com/en_US/downloads/dbm/pdf002_-_Bionate_product_description-processing-properties.pdf http://www.americanurethane.com/aboutu1.htm http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MTP641 http://us.synthesprodisc.com/EN-US/ http://www.depuy.com/corporate-information/about-depuy/history

21. Thank You