Table 2.

Preoperative and postoperative median Co and Cr concentrations (range) following metal-on-metal hip arthroplasty

Serum metal ion levels	ASR Resurfacing	ASR XL Head	Significance
Median Co(μg/dl)
preoperative	0,02 (0 to 0,03)	0,00 (0 to 0,54)	0,504
6 weeks	0,06 (0,01 to 0,19)	0,07 (0 to 0,30)	0,780
3 months	0,04 (0 to 0,33)	0,10 (0 to 0,66)	0,143
6 months	0,07 (0,01 to 0,38)	0,14 (0,00 to 2,81)	0,134
1 year	0,14 (0 to 0,39)	0,27 (0 to 5,85)	0,068
2 years	0,09 (0,03 to 0,54)	0,36 (0,03 to 7,82)	0,011
Median Cr (μg/dl)
preoperative	0,020 (0,010 to 0,030)	0,026 (0,007 to 0,753)	0,293
6 weeks	0,100 (0,060 to 0,140)	0,101 (0,050 to 0,443)	0,802
3 months	0,137 (0,097 to 0,398)	0,176 (0,059 to 0,724)	0,404
6 months	0,170 (0,070 to 0,475)	0,253 (0,064 to 1,240)	0,099
1 year	0,207 (0,081 to 0,968)	0,324 (0,111 to 2,656)	0,051
2 years	0,141 (0,092 to 0,990)	0,458 (0,071 to 5,198)	0,005
Inclination in °
1 week	43,8 (35,1 to 60,0)	43,6 (30,4 to 60,3)	0,892
3 months	40,9 (35,4 to 61,2)	44,1 (30,7 to 61,3)	0,465
1 year	40,9 (34,9 to 59,3)	44,5 (34,4 to 60,4)	0,465
2 years	41,0 (35,0 to 61,0)	45,5 (28,0 to 68,0)	0,351
Arc of cover in mm
1 week	14,6 (7,7 to 19,2)	13,4 (5,4 to 19,9)	0,372
3 months	15,5 (7,0 to 19,0)	13,9 (5,2 to 19,9)	0,244
1 year	15,2 (8,2 to 19,1)	13,1 (5,7 to 17,9)	0,223
2 years	16,0 (7,6 to 19,5)	13,8 (6,0 to 20,2)	0,281

Mean values with their range are given for the inclination and the arc of cover.