SYSTEMIC RELEASE OF COBALT AND CHROMIUM AFTER UNCEMENTED TOTAL HIP-REPLACEMENT

We measured the levels of cobalt and chromium in the serum in three gr oups of patients after uncemented porous-coated arthroplasty. Group 1 consisted of 14 consecutive patients undergoing revision for aseptic l oosening. Group 2 comprised 14 matched patients in whom the arthroplas ty was stable and group 3 was 14 similarly matched patients with arthr itis awaiting hip replacement, Specimens were analysed using atomic ab sorption spectrophotometry. Aseptic loosening of a component resulted in a significant elevation of serum cobalt (p < 0.05), but not of seru m chromium. The relative risk of a component being loose, if the patie nt had a serum cobalt greater than 9.0 nmol/l, was 2.8.