BACKGROUND: There is increasing concern regarding the occurrence of adverse local tissue reactions (ALTRs) in metal-on-polyethylene (MoP) total hip arthroplasty (THA) patients due to mechanically assisted crevice corrosion at the head-neck modular taper junction. The utility of metal ion levels in evaluating MoP patients with head-neck taper has not been fully characterized. This study aimed to investigate the sensitivity and specificity of serum metal ions as a predictor of ALTR in MoP THA patients. METHODS: A total of 62 MoP THA patients in 2 cohorts were investigated: (1) ALTR on metal artifact reduction sequence magnetic resonance imaging (n = 43) and (2) without ALTR on metal artifact reduction sequence magnetic resonance imaging (n = 19). Receiver-operating characteristic curve was constructed to determine the sensitivity and specificity using different metal ion thresholds and the optimal metal ion cutoff values. RESULTS: The presence of ALTR was associated with significantly higher cobalt (8.9 ng/mL vs 0.3 ng/mL, P < .001), chromium (2.26 ng/mL vs 0.21 ng/mL, P < .001), and Co/Cr ratio (5.9 vs 2.0, P < .001). The sensitivity and specificity for cobalt (1 ng/mL) was 95% and 94% and for Co/Cr ratio (2) was 83% and 72%, respectively. CONCLUSIONS: Although metal ion levels alone should not be relied on as the sole parameter to determine revision surgery, serum cobalt level of >1 ng/mL (1 ppb) and Co/Cr ratio >2 thresholds provide evidence-based practical information for surgeons when interpreting metal ion levels in MoP THA patients for clinically relevant head-neck taper corrosion.
BACKGROUND: There is increasing concern regarding the occurrence of adverse local tissue reactions (ALTRs) in metal-on-polyethylene (MoP) total hip arthroplasty (THA) patients due to mechanically assisted crevice corrosion at the head-neck modular taper junction. The utility of metal ion levels in evaluating MoPpatients with head-neck taper has not been fully characterized. This study aimed to investigate the sensitivity and specificity of serum metal ions as a predictor of ALTR in MoP THA patients. METHODS: A total of 62 MoP THA patients in 2 cohorts were investigated: (1) ALTR on metal artifact reduction sequence magnetic resonance imaging (n = 43) and (2) without ALTR on metal artifact reduction sequence magnetic resonance imaging (n = 19). Receiver-operating characteristic curve was constructed to determine the sensitivity and specificity using different metal ion thresholds and the optimal metal ion cutoff values. RESULTS: The presence of ALTR was associated with significantly higher cobalt (8.9 ng/mL vs 0.3 ng/mL, P < .001), chromium (2.26 ng/mL vs 0.21 ng/mL, P < .001), and Co/Cr ratio (5.9 vs 2.0, P < .001). The sensitivity and specificity for cobalt (1 ng/mL) was 95% and 94% and for Co/Cr ratio (2) was 83% and 72%, respectively. CONCLUSIONS: Although metal ion levels alone should not be relied on as the sole parameter to determine revision surgery, serum cobalt level of >1 ng/mL (1 ppb) and Co/Cr ratio >2 thresholds provide evidence-based practical information for surgeons when interpreting metal ion levels in MoP THA patients for clinically relevant head-neck taper corrosion.
Keywords:
adverse local tissue reaction; cobalt and chromium metal ion level; head-neck taper corrosion; metal-on-polyethylene total hip arthroplasty; pseudotumor prediction
Authors: Margaret A Weber; Matthew J Snyder; Kalain K Workman; Margaret M Sims; Clair N Smith; Deepak Kumar; Akshay V Daji; Camilo G Borrero; Andrew C Cordle; Anthony M DiGioia; Brian R Hamlin; Anton Y Plakseychuk; Kenneth L Urish Journal: J Arthroplasty Date: 2020-09-17 Impact factor: 4.435
Authors: Matthew T Houdek; Michael J Taunton; Cody C Wyles; Paul J Jannetto; David G Lewallen; Daniel J Berry Journal: J Arthroplasty Date: 2021-05-01 Impact factor: 4.435
Authors: Matthew J Snyder; Margaret A Weber; Joseph J Kromka; Margaret M Sims; Clair N Smith; Akshay V Daji; Deepak Kumar; Camilo G Borrero; Andrew C Cordle; Anthony M DiGioia; Brian R Hamlin; Anton Y Plakseychuk; Kenneth L Urish Journal: Arthroplast Today Date: 2022-01-18