title: The design of the acetabular component and size of the femoral head influence the risk of revision following 34 721 single-brand cemented hip replacements: a retrospective cohort study of medium-term data from a National Joint Registry.
abstract: Despite excellent results, the use of cemented   total hip replacement (THR) is declining. This retrospective cohort study   records survival time to revision following primary cemented THR   using the most common combination of components that accounted for   almost a quarter of all cemented THRs, exploring risk factors independently associated   with failure. All patients with osteoarthritis who had an Exeter   V40/Contemporary THR (Stryker) implanted before 31 December 2010   and recorded in the National Joint Registry for England and Wales   were included in the analysis. Cox's proportional hazard models   were used to analyse the extent to which risk of revision was related   to patient, surgeon and implant covariates, with a significance   threshold of p < 0.01. A total of 34 721 THRs were included in   the study. The overall seven-year rate of revision for any reason   was 1.70% (99% confidence interval (CI) 1.28 to 2.12). In the final   adjusted model the risk of revision was significantly higher in   THRs with the Contemporary hooded component (hazard ratio (HR) 1.88,    p < 0.001) than with the flanged version, and in smaller head   sizes (< 28 mm) compared with 28 mm diameter heads (HR 1.50,   p = 0.005). The seven-year revision rate was 1.16% (99% CI 0.69   to 1.63) with a 28 mm diameter head and flanged component. The overall   risk of revision was independent of age, gender, American Society   of Anesthesiologists grade, body mass index, surgeon volume, surgical   approach, brand of cement/presence of antibiotic, femoral head material   (stainless steel/alumina) and stem taper size/offset. However, the   risk of revision for dislocation was significantly higher with a   'plus' offset head (HR 2.05, p = 0.003) and a hooded acetabular component   (HR 2.34, p < 0.001). In summary, we found that there were significant differences   in failure between different designs of acetabular component and   sizes of femoral head after adjustment for a range of covariates.
authors.affiliation: The National Joint Registry for England and Wales, UK. simonjameson@doctors.org.uk
authors.forename: S S
authors.initials: SS
authors.lastname: Jameson
authors.forename: P N
authors.initials: PN
authors.lastname: Baker
authors.forename: J
authors.initials: J
authors.lastname: Mason
authors.forename: P J
authors.initials: PJ
authors.lastname: Gregg
authors.forename: N
authors.initials: N
authors.lastname: Brewster
authors.forename: D J
authors.initials: DJ
authors.lastname: Deehan
authors.forename: M R
authors.initials: MR
authors.lastname: Reed
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000379:methods*; D001843:Bone Cements / Q000009:adverse effects / Q000627:therapeutic use*; D004739:England; D005260:Female; D005270:Femur Head / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012042:Registries; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014852:Wales
chemical_list: D001843:Bone Cements