linkSTAR Sales Training Presentation

1、STAR Ankle History & Technique,Tom Loring SVP Worldwide Ankle Business Unit Small Bone Innovations Morrisville, Pennsylvania,November 9, 2010,The STAR Ankle,Hakon Kofoed Orthopaedic University Clinic, Frederiksberg Hospital, Copenhagen, Denmark,STAR Implant Design History,The Best Bone to Support a

2、Prosthesis Distal 10 mm of tibia (Hvid et al. CORR 1985),Upper 5 mm of talus,Soft Cancellous,Talar Blood Supply,Maintaining blood supply is critical Areas to avoid Sinus tarsi Posterior/Medial Use only surface cuts,Radiating end arteries from the sinus tarsi,History,1974 BP Cylindrical Fixed Bearing

3、,ICLH,1982 Newton,1975 Irvine,Mayo Conaxial Bath & Wessex TPR Thompson Parkridge Richards Waugh Oregon Smith,The Ankle Acts Like a Hinge,The STAR Ankle Circa 1978,Incorporation of known features,A two component device for cemented use Congruent with near anatomical features Wings for the talar facet

4、 joints Parallel bars for tibial fixation Survival rate at 12 years was 70% (Kofoed 1995, Foot Ankle Int.) Tibial component loosening was main cause of failure,Reduce the Stress!,Rotation and Translation Matter!,Mobile Bearing Allow for Rotation and Translation,Neutral,Rotation,Translation,2-Piece A

5、nkle Increases Poly Contact Stress Increases Cement/Bone Shear Stress Rotation Translation,High Contact Stress,High Contact Stress,1.7 mm movement in sagittal plane,Kofoed & Witt, Foot & Ankle Surg., 2000,Movement of Meniscus,What about coronal plane movement?,The STAR Ankle Circa 1984,Tibial compon

6、ent separated Flat metal plate Mobile bearing meniscus No significant poly wear Survival rate at 14 years was 73% (Kofoed & Sorensen 1998, JBJS (Br),The STAR Ankle Circa 1989,Prosthesis changed to uncemented CoCr with titanium plasma spray Survival rate at 12 years was 95% (Kofoed 2004, Clinical Ort

7、hopaedics),STAR US Clinical Trial,STAR Boise Kansas City Durham Columbus Iowa City Oakland Dallas Tampa Houston Jacksonville,Arthrodesis New York Philadelphia Los Angeles Miami Palo Alto Charlotte,ControlledNon-Randomized Trial,STAR Centers 158 cases,Arthrodesis Centers 79 cases,The STAR Ankle in th

8、e U.S.,IDE # granted by the FDA, June 29, 2000 Final data submission, March 2007 Advisory Panel approval, April 2007 STAR acquired by SBi in December 2008 Received US FDA PMA approval May 27, 2009 Over 16,000 implanted globally Continued access patients Results even better than pivotal Surgeon feedb

9、ack on instrument design Simplify the procedure Improve accuracy and repeatability,Factors Affecting Implant Longevity,What can we do?,Company Implant design Better metal surface finish Advanced UHMWPE Patient Weight Activity Smoking Surgeon Patient selection Implant orientation No scratching!,Bette

10、r techniques Better instruments Better UHMWPE,The future.,Instrument Design Considerations,Malalignment, Mobility & Stability Instruments cant solve these problems Instruments are for post-alignment Precise, Repeatable cuts Accurate drilling First Correct Osteotomies Supramalleolar Sliding medial ma

11、lleolus Calcaneal Achilles tendon lengthening,STAR Instrument Design,Develop Best-in-Class Instrumentation Worked with experienced STAR surgeons Focused Engineering Resources Design Input Evolution 16 Cadaver Labs Frequent Surgeon Interaction Team Effort Result Positive Reviews Users Non-Users,STAR

12、Instrumentation,Surgical Technique,Tibial Alignment Guide,Distal tibial resection Sets component orientation,Tibial Resection,Captured cut Multiple adjustment options Protection for maleoli,Determining Tibial Resection Level,Initial Talar Resection,Captured slot Fixation to talus Multiple options,Co

13、nfirm Resections,Simple check of initial resections Minimum requirement for 6 mm bearing,Talar Sizing Guide,Check talar component sizing Verify initial resection,Datum Concept,Single reference, 4 cuts Improved accuracy Improved repeatability,Datum Holder-Distractor,Datum placement,Datum Fixation,Thr

14、eaded shoulder pins for improved stability,Confirming Datum Position,Posterior Chamfer Cut,Partially captured for a flat cut,Anterior Chamfer Mill,Two overlapping passes,M/L Cuts,Place over the datum,M/L Cuts,Saw rotated around superior guide surface,Window Trial,Check of all talar cuts Same dimensi

15、ons as the talar implant,Window Trial,Keel milling Pins for stability,Keel Broach,Final keel preparation,Talar Component Seating,Barrel Hole Drilling,Tibial implant trial Adjust A/P Adjust M/L Adjust rotation Assess sizing,Box Chisel,Removal of remaining web of bone,Tibial Implant Impaction,Trial Mo

16、bile Bearing,Inserting Final Mobile Bearing,Final Fluoroscopic Images,Bone Graft Barrels and Close Capsule,Polyethylene - UHMWPE,Good Poly,Bad Poly,Cracker?,UHMWPE,Gamma Irradiation (sterilization) Creates Cross-Links (Good!) Improved Wear Performance Creates Free Radicals (Bad) ETO or Gas Plasma (s

17、terilization) No Free Radicals No Cross-Links (Bad!) Reduced Wear Performance Free Radicals Allow Oxidation Oxidation = White Banding Affects Mechanical Properties High Contact Stress Can Lead To Delamination Fatigue Failure What Can Be Done? Reduce Contact Stress Address the Free Radicals Limit Exp

18、osure to O2 Eliminate or Quench Free Radicals,Reduce the Stress!,Rotation and Translation Matter!,Mobile Bearing Allow for Rotation and Translation,Neutral,Rotation,Translation,2-Piece Ankle Increases Poly Contact Stress Increases Cement/Bone Shear Stress Rotation Translation,High Contact Stress,Hig

19、h Contact Stress,STAR UHMWPE,STAR Polyethylene Evolution Original Gamma Irradiation Packaged in Air Today Gamma Irradiation Packaged in Nitrogen Double Sealed PVA Less than 6 Months Old Early 2010 Gamma Irradiation Packaged in Nitrogen Double Sealed PVA and Foil Late 2010 Project X,STAR UHMWPE,Project X Goals Eliminate Free Radicals Improve Wear Per