Comparison of in vivo wear between polyethylene liners articulating with ceramic and cobalt-chrome femoral heads.
At yearly intervals we compared the radiological wear characteristics of 81 alumina ceramic femoral heads with a well-matched group of 43 cobalt-chrome femoral heads. Using a computer-assisted measurement system we assessed two-dimensional penetration of the head into the polyethylene liner. We used linear regression analysis of temporal data of the penetration of the head to calculate the true rates of polyethylene wear for both groups. At a mean of seven years the true rate of wear of the ceramic group was slightly greater (0.09 mm/year, SD 0.07) than that of the cobalt-chrome group (0.07 mm/year, SD 0.04). Despite the numerous theoretical advantages of ceramic over cobalt-chrome femoral heads, the wear performance in vivo of these components was similar.
Sychterz
C J
CJ
Anderson Orthopaedic Research Institute, Alexandria, Virginia 22307, USA.
Engh
C A
CA
Young
A M
AM
Hopper
R H
RH
Engh
C A
CA
D000368:Aged; D000537:Aluminum Oxide / Q000737:chemistry; D016022:Case-Control Studies; D002516:Ceramics / Q000737:chemistry*; D002858:Chromium Alloys / Q000737:chemistry*; D005260:Female; D005270:Femur Head; D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging; D006622:Hip Prosthesis; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D020959:Polyethylene / Q000737:chemistry*; D011474:Prosthesis Design; D011856:Radiographic Image Enhancement; D018709:Statistics, Nonparametric; D013499:Surface Properties
D002858:Chromium Alloys; D020959:Polyethylene; D000537:Aluminum Oxide