|
|
| General |
| Study Status |
Completed |
| 522 Number / Requirement Number |
PS110070 / PSS003 |
| Date Original Plan Accepted |
03/21/2017
|
| Date Current Plan Accepted |
07/23/2021
|
| Study Name |
Explant
|
| Device Name |
Metal transcend articulation system
|
| Root Document Number |
K004043
K021349
K031963
K041425
K042530
K043073
K043099
K041586
K041114
K061844
K060358
K060356
K053588
K052915
K051995
K051348
K070785
K080663
K082924
K110029
K081090
K091423
|
| General Study Protocol Parameters |
| Study Design |
Bench/Lab Study
|
| 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 |
The main study objective is to conduct an analysis of revised and retrieved cases of MOM THA involved in the Post-Market Surveillance study in order to correctly identify all failure modes. The study design is explant analysis.
|
| Study Population |
The study population is comprised of patients who have had a revised metal-on-metal hip.
|
| Sample Size |
There is not a control group.
|
| Key Study Endpoints |
The data collection for the study is new data collection
|
| Follow-up Visits and Length of Follow-up |
n/a
|
| Interim or Final Data Summary |
| Actual Number of Patients Enrolled |
Twelve (12) revised hips from the 522 clinical study (PS110070/PSS002) and an additional 25 hips from the Wright Medical
Technology (WMT) complaint database
|
| Actual Number of Sites Enrolled |
4
|
| Patient Followup Rate |
N/A
|
| Final Safety Findings |
The majority of failures of the 12 enrolled subjects occurred between 7
and 12 years, but all of the 25 retrievals from the WMT complaint
database failed between 4 months and 4 years.
Adverse Local Tissue Reaction (ALTR) was reported as primary cause
of failure for 12 out of the 37 cases (11 out of 12 explant subjects and
one out of 25 complaint retrievals) with a revised hip.
Out of the 37 explant subjects and complaint retrievals, 28 (75.7%)
reported severe implant-associated pain, 6 (16.2%) showed metal
hypersensitivity, 13 (35.1%) had device loosening, 1 (2.7%) was
reported to have infection and 12 (32.4%) had ALTR, which included,
presence of Aseptic lymphocyte- dominant vasculitis-associated lesion
(ALVAL), necrosis and pseudotumor.
Osteolysis was observed in 5 (13.5%) of the cases and 7 (18.9%) had
radiographic changes including device migration, subsidence, tilting and
radiolucencies. None of the patients showed signs of ossification or
iliopsoas impingement.
Metal ion levels ranged from 0.1 mg/L to 26 mg/L.
There was a positive relationship between total bearing wear and blood
ion levels. There was no strong correlation between metal ion levels and
bearing wear, although there was a general trend.
The articular wear contributed more to the overall wear of the system as
compared to the taper wear.
The female taper wore more than the male taper. This indicated that not
only wear, but also corrosion contributed significantly to ALTR and
high ALVAL scores.
There was no strong correlation between metal ion levels and bearing
wear, although there was a general trend.
There was no strong correlation between taper wear and bearing wear.
There was no correlation between taper wear and patient BMI.
There was no correlation between taper wear and ALTR occurrence.
There was no correlation between taper wear and pseudotumor
occurrence.
|
| Final Effectiveness Findings |
Not applicable, explant analysis study focused on safety
|
| Study Strengths and Weaknesses |
Strengths: Detailed information addressing the mode(s) and cause(s) of failure of MoM devices.
Weaknesses: the MDT retrieval group has limited demographic information
|
| Recommendations for Labeling Changes |
No labeling changes are recommended because the device is no longer marketed
|
