Early surveillance of ceramic-on-metal total hip arthroplasty.
Ceramic-on-metal (CoM) is a relatively new bearing combination for total hip arthroplasty (THA) with few reported outcomes. A total of 287 CoM THAs were carried out in 271 patients (mean age 55.6 years (20 to 77), 150 THAs in female patients, 137 in male) under the care of a single surgeon between October 2007 and October 2009. With the issues surrounding metal-on-metal bearings the decision was taken to review these patients between March and November 2011, at a mean follow-up of 34 months (23 to 45) and to record pain, outcome scores, radiological analysis and blood ion levels. The mean Oxford Hip Score was 19.2 (12 to 53), 254 patients with 268 hips (95%) had mild/very mild/no pain, the mean angle of inclination of the acetabular component was 44.8(o) (28(o) to 63(o)), 82 stems (29%) had evidence of radiolucent lines of > 1 mm in at least one Gruen zone and the median levels of cobalt and chromium ions in the blood were 0.83 μg/L (0.24 μg/L to 27.56 μg/L) and 0.78 μg/L (0.21 μg/L to 8.84 μg/L), respectively. The five-year survival rate is 96.9% (95% confidence interval 94.7% to 99%). Due to the presence of radiolucent lines and the higher than expected levels of metal ions in the blood, we would not recommend the use of CoM THA without further long-term follow-up. We plan to monitor all these patients regularly.
Musgrave Park Hospital, Stockman's Lane, Belfast, BT9 7JB, UK.
J C
JC
Hill
Musgrave Park Hospital, Stockman's Lane, Belfast, BT9 7JB, UK.
O J
OJ
Diamond
Musgrave Park Hospital, Stockman's Lane, Belfast, BT9 7JB, UK.
S
S
O'Brien
Private Hospital Worbstrasse, 324 CH 3073 Guemligen, Switzerland.
J G
JG
Boldt
Institute of Clinical Science 'B' , Grosvenor Road, Belfast BT12 6BJ, UK.
M
M
Stevenson
Musgrave Park Hospital, Stockman's Lane, Belfast, BT9 7JB, UK.
D E
DE
Beverland
D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D002516:Ceramics; D002857:Chromium / Q000097:blood; D003035:Cobalt / Q000097:blood; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D007477:Ions / Q000097:blood; D008297:Male; D008670:Metals / Q000097:blood; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery; D010147:Pain Measurement; D011159:Population Surveillance; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation; D016896:Treatment Outcome
D007477:Ions; D008670:Metals; D002857:Chromium; D003035:Cobalt
ceramic-on-metal; hard on hard bearings; total hip replacement