title: Taperosis: Does head length affect fretting and corrosion in total hip arthroplasty?
abstract: Tribocorrosion at the head-neck taper interface - so-called 'taperosis' - may be a source of metal ions and particulate debris in metal-on-polyethylene total hip arthroplasty (THA). We examined the effect of femoral head length on fretting and corrosion in retrieved head-neck tapers in vivo for a minimum of two years (mean 8.7 years; 2.6 to 15.9). A total of 56 femoral heads ranging from 28 mm to 3 mm to 28 mm + 8 mm, and 17 femoral stems featuring a single taper design were included in the study. Fretting and corrosion were scored in three horizontally oriented concentric zones of each taper by stereomicroscopy. Head length was observed to affect fretting (p = 0.03), with 28 mm + 8 mm femoral heads showing greater total fretting scores than all other head lengths. The central zone of the femoral head bore taper was subject to increased fretting damage (p = 0.01), regardless of head length or stem offset. High-offset femoral stems were associated with greater total fretting of the bore taper (p = 0.04). Increased fretting damage is seen with longer head lengths and high-offset femoral stems, and occurs within a central concentric zone of the femoral head bore taper. Further investigation is required to determine the effect of increased head size, and variations in head-neck taper design.
authors.affiliation: London Health Sciences Centre, University Hospital, 339 Windermere Road, London, Ontario N6A 5A5, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Del Balso
authors.affiliation: Western University, 1151 Richmond Street, London, Ontario N6A 3K7, Canada.
authors.forename: M G
authors.initials: MG
authors.lastname: Teeter
authors.affiliation: London Health Sciences Centre, University Hospital, 339 Windermere Road, London, Ontario N6A 5A5, Canada.
authors.forename: S C
authors.initials: SC
authors.lastname: Tan
authors.affiliation: London Health Sciences Centre, University Hospital, 339 Windermere Road, London, Ontario N6A 5A5, Canada.
authors.forename: B A
authors.initials: BA
authors.lastname: Lanting
authors.affiliation: University Hospital, 339 Windermere Road, London, Ontario N6A 5A5, Canada.
authors.forename: J L
authors.initials: JL
authors.lastname: Howard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip; D003343:Corrosion; D005260:Female; D005270:Femur Head; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design / Q000009:adverse effects*; D011475:Prosthesis Failure / Q000209:etiology*; D012189:Retrospective Studies
keywords: corrosion; fretting; taperosis; total hip arthroplasty