|
General |
Study Status |
Completed |
522 Number / Requirement Number |
PS110038 / PSS002 |
Date Original Plan Accepted |
07/06/2012
|
Date Current Plan Accepted |
09/28/2012
|
Study Name |
Explant Analysis
|
Device Name |
Depuy pinnacle metal-on-metal acetabular cup liners
|
Root Document Number |
K073413
K080991
K070359
K003523
K082239
K040627
K093646
K083642
K002883
K023786
K062426
K090998
K073570
K070554
K042992
K061221
K082585
|
General Study Protocol Parameters |
Study Design |
Other Study Design
|
Data Source |
New Data Collection
|
Comparison Group |
No Control
|
Analysis Type |
Descriptive
|
Study Population |
Transit. Adolescent B (as adults) : 18-21 yrs,
Adult: >21
|
Detailed Study Protocol Parameters |
Study Objectives |
This is an explant analysis study. Explanted devices will be retrieved from Pinnacle and ASR patients participating in 522 investigations and from patients outside of the 522 study whose surgeons agreed to follow protocol defined steps for retrieval and analysis.
|
Study Population |
Explanted devices from patients who received the Pinnacle or ASR in the post-market environment.
|
Sample Size |
Consecutive available devices for retrieval will be enrolled.
|
Key Study Endpoints |
Modes and causes of implant failure
|
Follow-up Visits and Length of Follow-up |
Not applicable. This is an analysis of explanted devices.
|
Interim or Final Data Summary |
Actual Number of Patients Enrolled |
ASR-XL: Stage 1 analysis – 1620 retrievals; Stage 2 analysis – 1266 retrievals Pinnacle Ultamet: Stage 1 analysis – 327 retrievals
|
Actual Number of Sites Enrolled |
8 sites initiated
|
Patient Followup Rate |
Not applicable.
|
Final Safety Findings |
The majority of failures occurred between 1 to 7 years. The main causes for ASR-XL revision surgery listed are: ALTR (46.0%), Pain (45.0%), Other (26.0%), Noise (3.6%), Dislocation (0.4%), Cup Loosening (11.3%). The main causes for Pinnacle Ultamet revision surgery listed are: ALTR (59.0%), Pain (60.0%), Other (8.3%), Noise (5.2%), Dislocation (6.1%), Cup Loosening (13.1%), Infection (5.8%), Osteolysis (15.3%), Malalignment (2.1%).
Forty-six percent (46.0%) of ASR-XL explants and fifty-nine percent (59.0%) of Pinnacle cups were linked to ALTRs. Median ALVAL scores of 6 were seen for explants with accompanying tissue samples (N = 191 ASR: N = 41 Pinnacle). Percentage of explants with moderate scratching were ASR – 78.0%, Pinnacle – 83.0%. The median bearing wear rate (mm3/year) for the Pinnacle was 1.97 mm3/year and bearing wear rates for the ASR was 5.07 mm3/year (Site 1) and 3.41 mm3/year (Site 2). Higher volumetric wear was correlated to higher blood metal ion levels (N = 237 ASR and N = 49 Pinnacle) . The percentage of edge-loaded cups were 90.0% (Stage 2) for ASR and 85.0% (Stage 2) for Pinnacle. No gender difference was associated with edge-loading. The percentages of tapers exhibiting Goldberg scores between 3–4 were 73.5% for ASR and 84.0% for Pinnacle, respectively. Goldberg scores tended to be higher for male patients than female patients.
|
Final Effectiveness Findings |
Not applicable, explant analysis study focused on safety.
|
Study Strengths and Weaknesses |
The number of explants is a major strength of this post-market surveillance study as the number of explants included in the study far exceeded the goal of 80 to 100 explants. A weakness of the study is insufficient cross-sectional connection to clinical/patient data and lack of complete volumetric analyses (taper wear unquantified), therefore not all endpoints for their explant protocol could be evaluated
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Recommendations for Labeling Changes |
No labeling changes are recommended because the device is no longer marketed.
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