Table 1.

Comparison of blood cobalt and chromium levels in CoCr JAs.

Reference	Medium	Device type	Patients, n	Duration	Co	Cr
Total hip replacement
Lainiala et al. (31)	Whole blood	CoCr	1335	Measurement lasts for 12 years	2.5 (0.1;192)	1.7 (0.1;115)
Pozzuoli et al. (105)	Whole blood	Group 1 (n  = 34): CoCr (cup and head)	68	Group 1 follow-up: 7 years	1.2 (0.6;13.6)	0.8 (0.1;7.3)
		Group 2 (n  = 34): Ti-6Al-4V (cup)-ceramic (head)		Group 2 follow-up: 7 years	0.6 (0.6;2.5)	0.3 (0.1;2.5)
Civinini et al. (106)	Serum	Modular dual-mobility	37	Mean 5.1 years (2–10) after surgery	1.99 (0.07;16.05)	2.08 (0.02;11.8)
Kim et al. (107)	Serum	Bearing (28 mm Metasul, Zimmer); Stem (Wagner Cone, Zimmer (n  = 52); CLS Spotorno, Zimmer (n  = 19))	71	Follow-up: 5 years	4.14 (0.13;4.14)	6.89 (0.40;6.89)
				Group A (n  = 62) follow-up between 5 years and the minimum 10 years (10–18.6 years)	(0.01;1.01)	(0.20;1.82)
				Group B (n  = 9) follow-up between 5 years and the minimum 10 years (10–18.6 years)	18.97	19.37
Lehtovirta et al. (108)	Whole blood	CoCr	69	Follow-up: 30 months	11.0 (0.6;108.5)	3.7 (0.4;29.9)
Ahmed et al. (109)	Whole blood	36 mm CoCr Pinnacle (Corail THA System)	55	Follow-up: 3– 9 years	24 ± 29	13.2 ± 13.3
Ando et al. (110)	Whole blood	Magnum group (femoral head between 38 mm and 52 mm)	116	Magnum group (n  = 62) follow-up: 5 years	1.16 ± 1.32	1.2 ± 1.9
		Conventional group; (28 mm or 32 mm femoral head)		Conventional group (n  = 54) follow-up: 5 years	3.77 ± 9.8	2.6 ± 4.9
Hip resurfacing
Lainiala et al. (31)	Whole blood	CoCr	890	Measurement lasts for 12 years	1.2 (0.1;225)	1.4 (0.1;125)
Lehtovirta et al. (108)	Whole blood	CoCr	13	Follow-up: 30 months	3.9 (1.5;16.2)	3.9 (1.5;7.2)
Ahmed et al. (109)	Whole blood	ASR, BHR, Cormet (Stryker), Corin (Cirenchester, UK)	50	Follow-up: 3–9 years	28.2 ± 44.2	19.6 ± 29.5
Grammatopoulos et al. (27)	Serum	BHR (n  = 26); conserve hip resurfacing (n  = 12)	38	Follow-up: 11 months (0-37)	4.3 (0.7;67.1) (17.6)	9.1 (1.2;69.5) (15.6)
Underwood et al. (32)	Whole blood	ASR (n  = 66)	130	Mean follow-up: 35 months (7-59)	13.5 (0.5;167)	9.8 (0.2;11.9)
		BHR (n  = 64)		Mean follow-up: 49 months (10-121)	10.2 (0;167)	4.8 (0.4;183)
Total knee replacement
Lons et al. (111)	Whole blood	Posterior stabilized TKRs CoCr (Fem) Ti (Tib)	66	Preoperative (mean (min; max))	0.23 (0.03;1.18)	0.48 (0.02;1.7)
				1-year follow-up (mean (min; max))	1.34 (0.20;2.91)	1.23 (0.1;2.81)
Lützner et al. (112)	Plasma	CoCr – Columbus Knee System; Standard – Not coated (n  = 59); Coated- AS coating (Cr layer, CrN–CrCN layers and ZrN layer) (n  = 61)	120	Standard preoperative	0.67 ± 0.54	0.50 ± 0.42
				Standard 1-year follow-up	0.50 ± 0.44	0.35 ± 0.31
				Coated preoperative	0.53 ± 0.33	0.54 ± 0.60
				Coated 1-year follow-up	0.45 ± 0.37	0.31 ± 0.15
Savarino et al. (113)	Serum	Group I – Stable TKRs (n  = 24) (CoCr (Fem+ Tib) = 7; CoCr (Fem) and Ti (Tib)=17); group II – Failed TKRs (n  = 35) (CoCr (Fem + Tib) = 15;CoCr (Fem) and Ti (Tib): 20)	59	Group I: Mean follow-up in months (range): 39 (10 to 108)	0.44 (0.08;4.65)	0.24 (0.06;1.39)
				Group II – Mean follow-up in months (range) 30 (8–74)	1.10 (0.08;8.80)	0.45 (0.06;1.44)
Reiner et al. (114)	Whole blood	PFC Sigma; CoCr (Fem); Ti (Tib)	22	Preoperative	0.006 (0.005;0.141)	0.251 (0.052;1.297)
				1-year follow-up	0.243 (0.122;0.615)	0.268 (0.000;1.984)
Luetzner et al. (115)	Serum	Foundation Knee System CoCr (Fem+ Tib): Unilateral TKR (n  = 23), Bilateral TKR (n  = 23)	41	Unilateral : Mean follow-up in 59 months (median 66 months)	3.28 (1.40;4.50)	0.92 (0.73;1.32)
				Bilateral: Mean follow-up in 59 months (median 66 months)	4.28 (2.10;5.40)	0.98 (0.38;1.64)
Garrett et al. (116)	Serum	Profix : CoCr (Fem) (n  = 23); OxZr (Fem) (n  = 14)	37	CoCr (nmol/L): Mean follow-up in 66 months	3.00 (0.00;91.00)	9.00 (3.00;85.00)
				OxZr (nmol/L): Mean follow-up in 48 months	2.50 (1.00;10.00)	8.0 (1.00;12.00)
Masoumiganjgah et al (117)	Whole blood (Cr), Serum (Co)	Triathlon Knee System CoCr (n  = 11) – ACS Knee System CoCr with titanium nitride coating (n  = 11)	22	Triathlon mean follow-up: 50 months (nmol/L)	4 (2;9)	16 (10;19)
				ACS mean follow-up: 50 months (nmol/L)	5 (3;9)	15.5 (10;23)
Gupta et al. (118)	Serum	Attune Knee System CoCr (Fem + Tib)	1	17 months after the primary TKR	2.4 (0.08;0.5 reference)	>1000 (0.06;0.93 reference)
Ho et al. (119)	Serum	Vanguard System – Custom titanium alloy (Ti-6Al-4V)	1	24 months after the primary TKR	0.3	0.4
Kenny et al. (120)	Whole blood	AGC Total Knee System, Modular Design	1	84 months after the primary TKR	8.65	2.35
Liu et al. (121)	Whole blood	Loosened (n  = 20)- 4 Ti-6Al-4V + 16 CoCr; stable (n  = 20) - 5 Ti-6Al-4V + 16 CoCr; Control (n  = 20) – no implant	60	Loosened	116.1 ± 49.2	108.1 ± 40.7
				Stable	0.9 ± 0.9	10.1 ± 2.9
				Control	0.8 ± 0.5	5.8 ± 2.6
Shoulder replacement
Reiner et al. (122)	Whole blood	TSA group anatomic TSA: TESS (The Total Evolutive Shoulder System; Biomet): 11 Simpliciti (Tornier, Bloomington, MN, USA)): 6, Aequalis Anatomical (Tornier): 3 RSA group reverse TSA: Aequalis Reversed Shoulder Prosthesis (Tornier): 20	40	Control (n  = 23)	0.11 (0.03–0.19)	0.14 (0.04–0.99)
				TSA mean follow-up: 29.5 (8-52) months (n  = 20)	0.15 (0.03–0.48)	0.31 (0.09–1.26)
				RSA mean follow-up: 25.7 (19-37) months (n  = 20)	0.18 (0.1–0.66)	0.48 (0.17–2.41)
Pareek et al. (123)	Whole blood	Stryker ReUnion	72	Preoperative	0.38 ± 0.43	0.31 ± 0.43
				1-year follow-up	0.45 ± 0.49	0.31 ± 0.47

Co and Cr concentration in µg/L or ng/mL; AGC, anatomic graduated component; ASR, articular surface replacement; BHR, Birmingham hip resurfacing; Co, cobalt; CoCr, cobalt–chromium; Cr, chromium; CrN-CrCN, chromium nitride–chromium carbonitride; Fem, femoral component; JA, joint arthroplasty; OxZr, oxidized zirconium; PFC, press-fit condylar; RSA, reverse shoulder arthroplasty; THA, total hip arthroplasty; Ti-6Al-4V, titanium alloy; Tib, tibial tray; TKR, total knee replacement; TSA, total shoulder arthroplasty; ZrN, zirconium nitride.