Cobalt (Co) and Chromium (Cr)
The main indication for cobalt and chromium levels is in assessing wear of metal-on-metal hip replacements.
For adults, blood taken into a 4mL EDTA tube
Send at ambient temperature to the laboratory. If unavoidable, samples can be refrigerated overnight.
Relevant clinical details, including the reason for the request.
The samples are sent to a referral laboraotory for analysis with results expected back within 2 weeks.
Less than 10 nmol/L
MHRA Cobalt threshold (7ppb) for patients with MoM hip joints 120 nmol/L
(To convert from nmol/L to µg/L - multiply by 0.059)
Less than 40 nmol/L
MHRA Chromium threshold (7ppb) for patients with MoM hip joints is 135 nmol/L
(To convert from nmol/L back to µg/L - multiply by 0.052)
- MHRA information on metal on metal hip replacements
- Updated MHRA Management Guidance June 2017
- NICE TA304 Total hip replacement and resurfacing arthroplasty for end-stage arthritis of the hip
- For more information on heavy metals visit Lab Tests Online
Page last updated: 07/02/2019