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. 2023 Jul 1;105-B(7):775-782.
doi: 10.1302/0301-620X.105B7.BJJ-2022-1359.R1.

Are serum cobalt and chromium levels predictors for patient-reported outcome measures in the ASR hip resurfacing arthroplasty?

Maarten C Koper  1 , Reinier W A Spek  2 , Max Reijman  1 , Eline M van Es  1 , Sara J Baart  3 , Jan A N Verhaar  1 , P K Bos  1
Affiliations

Are serum cobalt and chromium levels predictors for patient-reported outcome measures in the ASR hip resurfacing arthroplasty?

Maarten C Koper et al. Bone Joint J. .

Abstract

Aims: The aims of this study were to determine if an increasing serum cobalt (Co) and/or chromium (Cr) concentration is correlated with a decreasing Harris Hip Score (HHS) and Hip disability and Osteoarthritis Outcome Score (HOOS) in patients who received the Articular Surface Replacement (ASR) hip resurfacing arthroplasty (HRA), and to evaluate the ten-year revision rate and show if sex, inclination angle, and Co level influenced the revision rate.

Methods: A total of 62 patients with an ASR-HRA were included and monitored yearly postoperatively. At follow-up, serum Co and Cr levels were measured and the HHS and the HOOS were scored. In addition, preoperative patient and implant variables and the need for revision surgery were recorded. We used a linear mixed model to relate the serum Co and Cr levels to different patient-reported outcome measures (PROMs). For the survival analyses we used the Kaplan-Meier and Cox regression model.

Results: We found that an increase of one part per billion (ppb) in serum Co and Cr levels correlated significantly with worsening of the HHS in the following year. This significant correlation was also true for the HOOS-Pain and HOOS-quality of life sub scores. The overall ten-year survival rate in our cohort was 65% (95% confidence interval (CI) 52.5 to 77.6). Cox regression analysis showed a significant hazard ratio (HR) of 1.08 (95% CI 1.01 to 1.15; p = 0.028) for serum Co level. No significance was found with sex or inclination angle.

Conclusion: This study shows that increasing serum Co and Cr levels measured in patients with an ASR-HRA are predictive for deterioration in HHS and HOOS subscales in the following year. Increasing serum Co and Cr should forewarn both surgeon and patient that there is a heightened risk of failure. Continued and regular review of patients with an ASR-HRA implant by measurement of serum Co/Cr levels and PROMs remains essential.

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Conflict of interest statement

None declared.

References

    1. Daniel J , Pynsent PB , McMinn DJW . Metal-on-metal resurfacing of the hip in patients under the age of 55 years with osteoarthritis . J Bone Joint Surg Br . 2004 ; 86-B ( 2 ): 177 – 184 . 10.1302/0301-620x.86b2.14600 , 15046429
    1. Treacy RBC , McBryde CW , Pynsent PB . Birmingham hip resurfacing arthroplasty. A minimum follow-up of five years . J Bone Joint Surg Br . 2005 ; 87-B ( 2 ): 167 – 170 . 10.1302/0301-620x.87b2.15030 , 15736736
    1. Vale L , Wyness L , McCormack K , McKenzie L , Brazzelli M , Stearns SC . A systematic review of the effectiveness and cost-effectiveness of metal-on-metal hip resurfacing arthroplasty for treatment of hip disease . Health Technol Assess . 2002 ; 6 ( 15 ): 1 – 109 . 10.3310/hta6150 , 12137721
    1. Hart AJ , Skinner JA , Henckel J , Sampson B , Gordon F . Insufficient acetabular version increases blood metal ion levels after metal-on-metal hip resurfacing . Clin Orthop Relat Res . 2011 ; 469 ( 9 ): 2590 – 2597 . 10.1007/s11999-011-1930-y , 21656317
    1. Langton DJ , Jameson SS , Joyce TJ , Hallab NJ , Natu S , Nargol AVF . Early failure of metal-on-metal bearings in hip resurfacing and large-diameter total hip replacement: A consequence of excess wear . J Bone Joint Surg Br . 2010 ; 92-B ( 1 ): 38 – 46 . 10.1302/0301-620X.92B1.22770 , 20044676