1. Motion Preservation Projects Wayne Cheng, MD Head of Spine Service Associate Professor, Department of Orthopedic Surgery Loma Linda University Medical Center UCR meeting - Aug 23, 2009 Wayne Cheng, MD Head of Spine Service Associate Professor, Department of Orthopedic Surgery Loma Linda University Medical Center UCR meeting - Aug 23, 2009

2. HISTORY

3. Posterior Approach - Fusion Disease?

4. Spinal Biomechanics  Each vertebral body interacts with an adjacent vertebra by means of 5 articulating joints – disc and 4 facets  Biomechanics of a functional spine unit (FSU or motion segment) are determined by interaction of the disc, facets and ligaments  FSU’ have 3 main roles:  stabilize the vertebra relative to each other protect the nerves and each other from excessive loads  provide proper function for each FSU, the spine, and ambulation of the body as a whole  transfer and share loads in the spinal column.  Each vertebral body interacts with an adjacent vertebra by means of 5 articulating joints – disc and 4 facets  Biomechanics of a functional spine unit (FSU or motion segment) are determined by interaction of the disc, facets and ligaments  FSU’ have 3 main roles:  stabilize the vertebra relative to each other protect the nerves and each other from excessive loads  provide proper function for each FSU, the spine, and ambulation of the body as a whole  transfer and share loads in the spinal column. White and Panjabi Clinical Biomechanics of the Spine, 2nd Ed., 1990, J.B. Lippincot Philadelphia

5. TOTAL DISC REPLACEMNT Charite’ (depuy)Prodisc (synthes) Maverick (Medtronic) Flexicore (stryker)

6. Total Facet Arthroplasty System

7. POSTERIOR DYNAMIC STABILIATION

8. How much motion?

9. Questions  How stable? Replace all joints +

10. Questions  How stable? TDR + posterior dynamic stabilization +

11. Question: TDR Lateral approach

12. Equipments

13. Thank You