Saturday, August 6, 2011

Reviewing the Revision record of the Pinnacle hip over 5 years from the 2009 report of the National Joint of Registry of England and Wales (part 1 of x)

As you may know, I am interested in  reviewing the information available on the Pinnacle hip given this was the recommendation made by my surgeon for my revision.  My interest is in understanding the safety record behind this hip.  As you know, the Pinnacle hip is also made by Depuy just as the recalled ASR was made made by Depuy.

The first two things I reviewed in a prior post (
  • Incidence of complaints to the FDA on this hip- still have no idea what model of hip is associated with the adverse event reports to the FDA.
  • The one report which is referenced in the Pinnacle literature which deals with its safety record does not seem to be available anywhere for review.  No one seems to have that report to confirm what models (metal, ceramic, poly?????) this review involved.  The American Orthopedic Association doesn't have it.  Depuy doesn't have it. I contacted the physician who wrote the report and have not heard back from him yet.
My next attempt to review the Pinnacle in context with the performance (revision rates) of the other hips is to review the  National Joint Registry data from the  England and Wales data and subsequently review the Australian Registry data.

Here are some highlights from the 2009 report for  England and Wales.

This report covered 157, 232 primary hip replacements and 2462 were hip revisions.  (hard to say if these are the correct totals since they tried to link the primary data to other data bases.  It is unclear to me whether the data in the report is based on the totals initially collected or the totals reported that were linked to other data.  I find that data confusing at best!)

1.  The overall revision rates following primary hip replacements from 4/ 2003-11/2008 were 1% at one year, 2% at 3 years and 2.8% at 5 years.

2.  The overall revision rates following primary hip replacement were found to vary according to brand.

3.  The revision rates seem to be broken down by the part involved.  They reviewed several parts:
  • The stem
  • The cups
Remember, the hip prosthetic has three key  parts:  the femoral stem, the femoral head and the cup

4.  For the cemented stems, the most commonly used stem was the exeter V40 and had a revision rate of 1.3%.  This is a Stryker product.  The revision rates of the other cemented stems ranged from 1.9% to 3.8%.

5.  For the uncemented stems, the Corail  (a Depuy product) was the most commonly used  and that had a revision rate of 2.6% at three years.  the revision rates of the other cementless stems ranged from 1.9% to 3.8%.

6.  For the cemented cups, the Contemporary (Stryker product) was used most frequently, had a 3 year revision rate of 1.3%.  The revision rates of the other cemented cups ranged from .4% to 2.2%.

7.   For uncemented cups, the Pinnacle, which was used most frequently had a 3 year revision rate of 2.2%.  The revision rates of the other uncemented cups ranged from 1.1% to 2.8%.

8.  There was only weak evidence that the revision rate varied according to bearing surface.

I was somewhat surprised at the low revision rates in this particular report for not just Pinnacle but for all of the hips when reviewing the actual revision data over a 5 year period.

In the next post, I will look at the revision rates overall for different bearing surfaces, causes of revisions and demographics of the revisions.

No comments:

Post a Comment