1. New Technologies and Challenges Joint Replacement
Prof Stephen Graves
Director AOA National Joint Replacement Registry

2. Australian Orthopaedic Association
National Joint Replacement Registry
(AOA NJRR)

3. AOA NJRR Commenced in 1999 State by State implementation
Fully National in 2002
Collaboration of Orthopaedic surgeons, Governments, Hospitals (Public and Private) and Industry
Funded entirely By Commonwealth
Quality information on Australian joint replacement surgery not available form any other source
Determines the outcome in particular the risk of revision

4. Changing Rate of Joint Replacement
All Joints 93.8% Hips 61.9% Knees %

5. Currently Approx 65,000 procedures p.a. In excess of $1 billion p.a.
Prostheses 35% of cost and increasing
Over 60% of procedures in private
The rate of increase is greater in private
By ,000 procedures p.a
What % in private?

6. Outcomes
Registry uses Revision is an indication of failure of a joint replacement procedure
Proportion of Procedures undertaken that are revisions
Hip 14.2% Knee 10%
2005 Hip 12.1% Knee 8.2%
As good or better than most countries

7. Comparison to Sweden Australia 20-25% (Estimated Hip and Knee)
Proportion of procedures that are revisions
Australia Hip 12.1% Knee 8.2%
Sweden Hip 7-8% Knee 7%
Risk of Revision Surgery is better indicator of success
Australia % (Estimated Hip and Knee)
Sweden % (Hip and Knee)

8. Expenditure Implications
Reducing proportion of revisions by 1% decreases revision procedures by 650 p.a.
($ 16 – 32 million)
If Australia had the same rate of revision for hip and knee replacement as Sweden there would be 3250 less revisions a year
($ 81 and 162 million p.a.)
Reduced by 2% p.a. since 2001

9. Why the difference
Detailed in Recent Report for the Australian Centre for Health Research (ACHR)
Data from AOA NJRR 2006 Annual Report
Identical demographics of patients receiving joint replacement surgery
Some differences in patient selection
Major differences in prostheses selection
Major differences in prostheses fixation
Greater uptake of new prostheses technology in Australia

10. FNOF outcomes by Age Monoblock Modular Bipolar
Data: 1st September 1999 to 31st December 2005

11. Outcomes related to Category of Prostheses for Treatment of FNOF
Modular and bipolar better than monoblock
Differences are greatest in the younger age groups. (less than 75, and 75-84)
Bipolar may be better than Modular except in over 85 yr old age group
Cement fixation much better no matter what type of prostheses

12. Outcomes: Conventional Primary Total Hip
Data: 1st September 1999 to 31st December 2005

13. Outcomes by Age & Fixation
Under 55
55-64
65-74
Over 75

14. Trends in Prosthesis Fixation Conventional Primary THR

15. Resurfacing Hip Replacement
Increasing use
(8.9% of primary THR 2005)
Increasing use of prostheses other than the Birmingham
(96.3% 2001 and 63.5% 2002)

16. Outcomes: Resurfacing V Conventional THR (OA only)
Data: 1st September 1999 to 31st December 2005

17. Cumulative Percentage Revision by Gender
Data: 1st September 1999 to 31st December 2005

18. Cumulative Percentage Revision by Age
Data: 1st September 1999 to 31st December 2005

19. Approach to differences in categories of prostheses and prostheses fixation
Many examples in both hip and knee replacement
Registry identified variation in general is responded to very quickly
Complexity in understanding and determining implication of findings
Best left for the profession to decide
AOA to establish Guidelines based on Registry Data

20. Registry is able to compare outcomes of Individual prosthesis
Least revised
Most revised
Those with a higher than anticipated rate of revision

21. Cemented Primary THR’s
Minimum 1000 Observed component years for least revised
Data: 1st September 1999 to 31st December 2005

22. Least Revised Hybrid and Cementless Primary THR’s
Minimum 1000 Observed component years
Less than 2% Revision at 2 years
Data: 1st September 1999 to 31st December 2005

23. Most Revised Cementless Components
Data: 1st September 1999 to 31st December 2005

24. Revision rates of different Resurfacing prostheses
Data: 1st September 1999 to 31st December 2005

25. Preservation Fixed

26. Genesis II Cementless Oxinium

27. Outcomes of New Prostheses
Prosthesis type
Number of prostheses with CRR 3 years or less
Compared to top 3 with CRR of 4 or more years and over 1000 procedures
Better
Same
Worse
Uni Knee 14 2 12
Cemented TKR 4
Cementless TKR 6
Cemented THR
Cementless THR 71 63 8
Total
103 32

28. New Prostheses
None have performed better than previously approved and well established prostheses
Many have higher revision rates
Some have been considerably worse
All are associated with increased expenditure

29. New Prostheses Considerations
Currently Class IIb
Europe recently changed to Class III
What clinical information should be required prior to approval ?
Clinical Trials
RSA studies
Do parameters need to be set ?
Is equivalence sufficient for approval ?
How are minor modifications to be handled ?
Innovation and development must be encouraged

30. Enhancing outcomes Focus on what is best for patient outcomes
Guidelines for joint surgery using Registry information (appropriate patient and appropriate procedure)?
Reduce prostheses choice? How?
Remove poor performing prostheses from list?
Reduce or cease funding for poor performing prostheses?
Regulate differently the introduction of new prostheses?
Is this experience relevant to other devices?