Post on 31-Dec-2015
description
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 TeesUK
Prospective study:2004 – 2008 n= 505
ASR resurfacing
N = 418
ASR XL (THR)
N = 87
Failures due to bearing surface wear
Failures due Taper failure of ASR THR
Failure due to ARMD of ASR & ASR xl
ASR THR 50% failure at 75 months
ASR resurfacing
North Tees JBJS Br August 2011
In response to our paper in same August JBJS
Prof fisher Prof Learmonth
Surgical error !
So what is the evidence ?
Failures by cup size ASR v ASR xl
44 46 48 50 52 54 56 58 60 62 640
10
20
30
40
50
60
70
80
90
100
ASRASR XL
% failures
Cup size
1. Comparison of ASR with BHR
Tony Nargol single series
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
Results ASR v BHRASR BHR ASR THR
No of patients
Mean F/U 3.8 yrs 5.2 yrs 4.5 yrs
ARMD Females
ARMD Males
ARMD Total
ARMD Rate 5.9 % 0 % 11.4 %
Cup position error ?
What was Depuy advice or warning on cup position ?
Whole Blood Metal Ion Levels and Component Positioning after Surface Replacement of the Hip: Early Results
American Hip and Knee and knee Society (AHKS)3rd Nov 2007
GH Isaac A Cobb
R McLennan-SmithR OakeshottT O’Sullivan
T SiebelT Schmalzried
TP Vail
UK, S Africa, Australia, Germany, USA
Metal Ion Data, Effect of Implant InclinationConsecutive patients, 4 centres, N= 50(24m)
24m Ion Level v Inclination Group
2.3
12.6
2.5
24.1
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
35-55 (42) 55+ (8)
Inclination Group (deg)
Ion
Le
ve
l (u
g/l
) Cr (ug/l)
Co (ug/l)
....... a standard cup angle (<55 degrees )
Recommended cup positions for resurfacing
• Depuy inclination up to 55 degrees (AAHKS 2007)
• Oxford : Safer zone (JBJS 92B )– 35-55 inclination– 10-30 anteversion
Failure numbers ASR and ASR xl by cup inclination Tony Nargol (TN)
< 35 35-40 40-45 45-50 50-55 55-60 >600
5
10
15
20
25
30
ASR & ASR xl
Cup inclination
No of cases
Failure numbers ASR and ASR xl by cup inclinationTony Nargol
< 35 35-40 40-45 45-50 50-55 55-60 >600
5
10
15
20
25
30
ASR & ASR xl
Cup inclination
No of cases
Number of failures below and above 55 cup inclination
greater than 55
less than 55
-80 -60 -40 -20 0 20 40
Number of failures below and above 55 cup inclination
greater than 55
less than 55
-80 -60 -40 -20 0 20 40
72 cases
Tony Nargol (TN) all ASR CUP POSITIONS
all >20070
10
20
30
40
50
60
70
45.740.7
INCLINATION
Mean cup inclination
25th-75th centiles
spread
TN all ASR cup position compared to other centres
all TN TN >2007 Hart Wrightington Oxford Treacy 0
10
20
30
40
50
60
70
80
45.740.7
49 5046.6
49
INCLINATION
ASR xl failures inclination & anteversion
20 25 30 35 40 45 50 55 60 650
10
20
30
40
50
Anteversion
inclination
ASR xl failures inclination & anteversion
20 25 30 35 40 45 50 55 60 650
10
20
30
40
50
Anteversion
inclination
18 failures inside zone 11 failures outside zone
ASR xl failures inclination & anteversion
20 25 30 35 40 45 50 55 60 650
10
20
30
40
50
Anteversion
inclination
18 failures inside zone 11 failures outside zone
Depuy 2010 target
ARMD failure of ASR
Inclination 44.4*
ARMD failure of ASR
45.0*
ARMD failure of ASR
41.5*
ARMD failure of ASR
41 *
ARMD failure of ASR
42 *
ARMD failure of ASR THR
40 *
ASR Xl mean cup inclinations
Failed
46.7 degrees
(NS difference)
non-failed
46.5 degrees
Other centres failure of ASR XL
• S Jones (Cardiff)• D Beverland• York• Norfolk & Norwich
Conclusion
• ASR Xl failing at 50% at 7 yrs • Majority are in safe zone
• Taper failure has no relationship to cup position
UK National joint registry for ASR XL
• 2010 5yr 12% failure of ASR XL
• 2011 6yr ? Double to 24%
• 2012 7r ?? Double again 50%
Message to Depuy
I implanted 87 ASR xl so I am not influencing the NJR figures