1. Accelerated Failure of the ASR XL at North Tees Tony Nargol, R Sidaginamale, PKR Mereddy, JN Gandhi, T Joyce DJ Langton, R Logishetty, University Hospital of North Tees UK

2. Prospective study:2004 – 2008 n= 505 ASR resurfacing N = 418 ASR XL (THR) N = 87

3. Failures due to bearing surface wear

4. Failures due Taper failure of ASR THR

5. Failure due to ARMD of ASR & ASR xl ASR THR 50% failure at 75 months ASR resurfacing

6. North Tees JBJS Br August 2011

7. In response to our paper in same August JBJS Prof fisherProf Learmonth

8. Surgical error ! So what is the evidence ?

9. Failures by cup size ASR v ASR xl % failures Cup size

10. 1. Comparison of ASR with BHR Tony Nargol single series

11. The Incidence of Adverse Reactions to Metallic Debris(ARMED) with two Resurfacing devices AVF Nargol DJ Langton, SS Jameson, T Joyce American academy (AAOS) 2010 University Hospital of North Tees, Stockton-on-Tees, UK School of Mechanical & Systems Engineering, Newcastle University

12. Results ASR v BHR

13. Cup position error ?

14. What was Depuy advice or warning on cup position ?

15. Whole Blood Metal Ion Levels and Component Positioning after Surface Replacement of the Hip: Early Results American Hip and Knee and knee Society (AHKS) 3 rd Nov 2007 GH Isaac A Cobb R McLennan-Smith R Oakeshott T O’Sullivan T Siebel T Schmalzried TP Vail UK, S Africa, Australia, Germany, USA

16. Metal Ion Data, Effect of Implant Inclination Consecutive patients, 4 centres, N= 50(24m)....... a standard cup angle (<55 degrees )

17. Recommended cup positions for resurfacing Depuy inclination up to 55 degrees (AAHKS 2007) Oxford : Safer zone (JBJS 92B ) – 35-55 inclination – 10-30 anteversion

18. Failure numbers ASR and ASR xl by cup inclination Tony Nargol (TN) Cup inclination No of cases

19. Failure numbers ASR and ASR xl by cup inclination Tony Nargol Cup inclination No of cases

20. Number of failures below and above 55 cup inclination

21. 72 cases

22. Tony Nargol (TN) all ASR CUP POSITIONS INCLINATION Mean cup inclination 25 th -75 th centiles spread

23. TN all ASR cup position compared to other centres INCLINATION

24. ASR xl failures inclination & anteversion inclination

25. ASR xl failures inclination & anteversion inclination 18 failures inside zone 11 failures outside zone

26. ASR xl failures inclination & anteversion inclination 18 failures inside zone 11 failures outside zone Depuy 2010 target

27. ARMD failure of ASR Inclination 44.4*

28. ARMD failure of ASR 45.0*

29. ARMD failure of ASR 41.5*

30. ARMD failure of ASR 41 *

31. ARMD failure of ASR 42 *

32. ARMD failure of ASR THR 40 *

33. ASR Xl mean cup inclinations Failed 46.7 degrees (NS difference) non-failed 46.5 degrees

34. Other centres failure of ASR XL S Jones (Cardiff) D Beverland York Norfolk & Norwich

35. Conclusion ASR Xl failing at 50% at 7 yrs Majority are in safe zone Taper failure has no relationship to cup position

36. UK National joint registry for ASR XL 2010 5yr 12% failure of ASR XL 2011 6yr ? Double to 24% 2012 7r ?? Double again 50%

37. Message to Depuy I implanted 87 ASR xl so I am not influencing the NJR figures