Just as a reminder/ Metal on metal hips should not be placed in patients with compromised Kidney function....Recall in prior posts, I asked the question: What does compromised/impaired Kidney function mean? Does it mean low creatinine levels? Does it mean one Kidney? Both?
This article is relates to the testing involved in identifying systemic issues the metal ions may have on the kidney, a topic I have discussed in previous posts.
Metal ions are cleared in the kidney which is why this is a topic of discussion.
SourceNephrology and Health Sciences, University of Parma, Parma, Italy.
BACKGROUND:Metal ions released from arthroplasty devices are largely cleared in urine, leading to high exposure in renal tissues. Validated early markers of renal damage are routinely used to monitor workers in heavy metal industries, and renal risk can be quantified in these industries. It is unclear if the ion levels in patients with metal-on-metal hips are sufficient to cause renal damage.
QUESTION:Does metal-on-metal (MOM) bearing use over a 10-year period lead to elevation of early renal markers compared with the levels expected in subjects with no metal exposure?
METHODS:We retrospectively reviewed 31 patients who underwent MOM hip resurfacings 10 years earlier. Whole blood specimens were collected for metal ion analysis, serum for creatinine estimation, and urine for timed metal ion output and renal markers. The renal marker levels of 30 age- and gender-matched subjects with no metal exposure and no known renal problems or diabetes mellitus were used as controls for renal markers.
RESULTS:Median serum creatinine level in the MOM group was 1.1 mg/dL (interquartile range, 1.0-1.2 mg/dL) and median creatinine clearance was 79.2 mL/min. In this cohort, the number of patients with markers of renal damage above the reference range was comparable to the controls. None of the renal markers were associated with metal levels.
CONCLUSION:The absence of elevation of renal markers in this cohort 10 years after MOM bearing implantation is reassuring. However, we believe surveillance through further longer-term, large-scale controlled trials are needed to monitor this arthroplasty-induced low-intensity (but long-term) trace element exposure to rule out potential nephrotoxicity.
[ I totally agree with their conclusion in light of the Stanford study that was published back in April of this year. Recall the April 11th post on the study by the Stanford researchers?] Here is that summary:
[my comments. What I like about the Parma Italy study above is that they are seeking early signs of systemic issues assocaited with hip replacement. There are not a lot of medical people out there really looking at the early testing for any systemic issues. Ditto for the carcingogenic issues. If you want tests done, you have to advocate for yourself. It is highly doubtful that an orthopedic surgeon is going to initiate such such tests to look at early systemic effects of the hip. Yes, they will order tests to determine the metal levels and the infection levels but that is about the extent of the testing. There is not a lot published on this topic which is why I spend so much time on it.