title: A comparative assessment of small-head metal-on-metal and ceramic-on-polyethylene total hip replacement.
abstract: Large-head metal-on-metal (MoM) total hip replacements (THR) have given rise to concern. Comparative studies of small-head MoM THRs over a longer follow-up period are lacking. Our objective was to compare the incidence of complications such as infection, dislocation, revision, adverse local tissue reactions, mortality and radiological and clinical outcomes in small-head (28 mm) MoM and ceramic-on-polyethylene (CoP) THRs up to 12 years post-operatively. A prospective cohort study included 3341 THRs in 2714 patients. The mean age was 69.1 years (range 24 to 98) and 1848 (55.3%) were performed in women, with a mean follow-up of 115 months (18 to 201). There were 883 MoM and 2458 CoP bearings. Crude incidence rates (cases/1000 person-years) were: infection 1.3 vs 0.8; dislocation 3.3 vs 3.1 and all-cause revision 4.3 vs 2.2, respectively. There was a significantly higher revision rate after ten years (adjusted hazard ratio 9.4; 95% CI 2.6 to 33.6) in the MoM group, and ten of 26 patients presented with an adverse local tissue reaction at revision. No differences in mortality, osteolysis or clinical outcome were seen. In conclusion, we found similar results for small-head MoM and CoP bearings up to ten years post-operatively, but after ten years MoM THRs had a higher risk of all-cause revision. Furthermore, the presence of an adverse response to metal debris seen in the small-head MOM group at revision is a cause for concern.
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Lübbeke
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Gonzalez
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Garavaglia
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Roussos
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Bonvin
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Stern
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Peter
authors.affiliation: Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, Geneva, CH-1211, Switzerland.
authors.forename: P
authors.initials: P
authors.lastname: Hoffmeyer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002484:Cementation; D002516:Ceramics; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D061825:Metal-on-Metal Joint Prostheses / Q000009:adverse effects*; D008875:Middle Aged; D017060:Patient Satisfaction; D020959:Polyethylene; D011446:Prospective Studies; D011474:Prosthesis Design / Q000379:methods; D016459:Prosthesis-Related Infections / Q000453:epidemiology; D012086:Reoperation; D013314:Stress, Mechanical; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D020959:Polyethylene
keywords: 28 mm head; Adverse local tissure reaction; Infection; Metal-on-metal; Osteolysis; Revision; Total hip replacement