Metal-on-Metal Hip Joint Prostheses: a Retrospective Case Series Investigating the Association of Systemic Toxicity with Serum Cobalt and Chromium Concentrations.

Abstract

INTRODUCTION:

There have been concerns about prosthesis failure and the potential for systemic toxicity due to release of cobalt and chromium from metal-on-metal hip joint prostheses (MoM-HP). There is conflicting evidence on whether there is a correlation between higher cobalt and chromium concentrations and systemic toxicity.

METHODS:

We undertook a retrospective review of consecutive patients with MoM-HP referred for outpatient review in toxicology clinics in London, UK, and in the USA recorded in the Toxicology Investigators Consortium (ToxIC) Registry from June 2011 to June 2015.

RESULTS:

Thirty-one cases were identified; the median (IQR) serum cobalt concentration was 10.0 (3.8-32.8) mcg/L, and the median (IQR) serum chromium concentration was 6.9 (3.7-18.7) mcg/L. Twenty-three (74.2%) had symptoms, most commonly lethargy, hearing loss, and tinnitus. The odds ratios of symptomatic/asymptomatic patients for metal ion concentrations above/below 7 mcg/L were 1.87 (95% CI 0.37-9.57, p = 0.45) and 0.60 (95% CI 0.10-3.50, p = 0.57) for cobalt and chromium, respectively. Two (6.5%) patients with systemic cobalt toxicity had median (IQR) serum cobalt concentrations significantly higher than those without systemic features (630.4 [397.6-863.2] mcg/L versus 9.8 [2.9-16.4] mcg/L; p = 0.017). However, overall, there were no differences between cobalt (p = 0.38) or chromium (p = 0.92) concentrations between symptomatic and asymptomatic patients and no clinical features or investigation results correlated with cobalt or chromium concentration.

CONCLUSION:

Two (6.5%) of 31 individuals referred for assessment of MoM-HP were diagnosed with systemic cobalt toxicity. However, despite a high prevalence of reported symptoms, neither symptoms nor investigation results correlated with serum cobalt or chromium concentrations.

• Authors: James H Ho, Jerrold B Leikin, Paul I Dargan, John R H Archer, David M Wood, Jeffrey Brent
• Journal: Journal of medical toxicology : official journal of the American College of Medical Toxicology (J Med Toxicol) Vol. 13 Issue 4 Pg. 321-328 (12 2017) ISSN: 1937-6995 [Electronic] United States
• PMID: 28900863 (Publication Type: Journal Article, Multicenter Study)

Chemical References

• Biomarkers
• Chromium
• Cobalt

Topics

• Aged
• Arthroplasty, Replacement, Hip (adverse effects, instrumentation)
• Biomarkers (blood)
• Chromium (blood, poisoning)
• Cobalt (blood, poisoning)
• Female
• Hip Prosthesis (adverse effects)
• Humans
• London (epidemiology)
• Male
• Metal-on-Metal Joint Prostheses (adverse effects)
• Middle Aged
• Odds Ratio
• Poisoning (blood, diagnosis, epidemiology)
• Prevalence
• Prosthesis Failure
• Registries
• Retrospective Studies
• Risk Factors
• Time Factors
• Treatment Outcome
• United States (epidemiology)