Blood and urine metal ion levels in young and active patients after Birmingham hip resurfacing arthroplasty

Abstract

This is a longitudinal study of the daily urinary output and the concentrations in whole blood of cobalt and chromium in patients with metal-on-metal resurfacings over a period of four years. Twelve-hour urine collections and whole blood specimens were collected before and periodically after a Birmingham hip resurfacing in 26 patients. All ion analyses were carried out using a high-resolution inductively-coupled plasma mass spectrometer. Clinical and radiological assessment, hip function scoring and activity level assessment revealed excellent hip function. There was a significant early increase in urinary metal output, reaching a peak at six months for cobalt and one year for chromium post-operatively. There was thereafter a steady decrease in the median urinary output of cobalt over the following three years, although the differences are not statistically significant. The mean whole blood levels of cobalt and chromium also showed a significant increase between the pre-operative and one-year post-operative periods. The blood levels then decreased to a lower level at four years, compared with the one-year levels. This late reduction was statistically significant for chromium but not for cobalt. The effects of systemic metal ion exposure in patients with metal-on-metal resurfacing arthroplasties continue to be a matter of concern. The levels in this study provide a baseline against which the in vivo wear performance of newer bearings can be compared.

Serum metal ion levels after rotating-hinge knee arthroplasty: comparison between a standard device and a megaprosthesis

“…Daniel et al [5,14] reported a significant increase of Co and Cr in the blood at one year follow-up to metal-on-metal hip resurfacing, with a decreasing trend at four and six years after surgery. Within metal-on-metal hip resurfacing, higher levels of metal ions are observed in patients with smaller device diameter [1,11,12,14,22,23].…”

“…Case et al [3] discovered the possibility of DNA damage due to Co and Cr following metal-on-polyethylene hip arthroplasty. Furthermore, there are concerns about the hazard of delayed-type hypersensitivity reactions, nephrotoxicity and teratogenicity [2,4,5].…”

“…It is well known that metal-on-metal resurfacing prostheses are associated with elevated concentrations of metal ions within the hip joint, the periarticular soft tissues and systemically due to ionization effects from the bearing surface [5][6][7][8]. Imanishi et al [9], Back et al [6], Daniel et al [5], Engh et al [10], Antoniou et al [11], Witzleb et al [12] and Savarino et al [7,13] demonstrated that the levels of Co and Cr ions increase within the first three months to two years following metal-on-metal THA.…”

“…Imanishi et al [9], Back et al [6], Daniel et al [5], Engh et al [10], Antoniou et al [11], Witzleb et al [12] and Savarino et al [7,13] demonstrated that the levels of Co and Cr ions increase within the first three months to two years following metal-on-metal THA. In the study of Imanishi et al [9], there was no significant additional increase of serum metal ion concentration at the one year follow-up, whereas Back et al [6] and Daniel et al [5,14] observed a decreasing trend of serum concentration between one and six years. Beyond a 30-year follow-up, Sauvè et al [15] observed five times and three times higher serum levels of Co and Cr, respectively, following metal-on-metal THA compared with a control group.…”

Is Patient Selection Important for Hip Resurfacing?

“…Clinical disadvantages of hip resurfacing include the risk of femoral neck fracture [6,63], component malpositioning secondary to increased surgical complexity [20,24], femoral component loosening [5,8,18], decreased head-neck offset causing impingement [22,24], and metal ion production [36,59]. In the 1970s, hip resurfacing with metal femoral components and cemented polyethylene acetabular components was popular, but early failures (30% to 56%) [50,85] within 5 years resulting from osteolysis and component loosening caused them to fall out of favor [7,50,85].…”