title: Relationship between biometric characteristics and stem size of uncemented hip prostheses.
abstract: The authors examined 2329 uncemented hip prosthesis stems (AncaFit stem, Wright Medical Technology, Arlington, TN, USA) implanted between 1996 and 2004 due to primary coxarthrosis. This is the most commonly used stem in the Emilia-Romagna region, in northern Italy, according to data from the Register of Orthopaedic Prosthetic Implants (RIPO). It is produced in eight sizes for each side. We analyzed the relationship between stem size and anthropometric data. Among the patients, 49.5% were men and 50.5% were women; mean age at surgery was 64.1 years (SD 9.1); mean height was 167 cm (SD 8.4), and mean weight was 75.7 kg (SD 12.7). Multifactorial analysis demonstrated that stem size was influenced by sex, age, and height, but not by weight. Besides this, there was an interaction between sex and age: in women, but not in men, the stem size increased with aging.
authors.affiliation: Laboratorio di Tecnologia Medica, Istituti Ortopedici Rizzoli--Bologna, Italy. declerico@tecno.ior.it
authors.forename: Manuela
authors.initials: M
authors.lastname: De Clerico
authors.forename: Barbara
authors.initials: B
authors.lastname: Bordini
authors.forename: Susanna
authors.initials: S
authors.lastname: Stea
authors.forename: Marco
authors.initials: M
authors.lastname: Viceconti
authors.forename: Aldo
authors.initials: A
authors.lastname: Toni
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000379:methods; D001827:Body Height; D001835:Body Weight; D002484:Cementation; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design